text: // CodeMirror v5.0, copyright (c) by Marijn Haverbeke and others
  // Distributed under an MIT license: http://codemirror.net/LICENSE
  
  // This is CodeMirror (http://codemirror.net), a code editor
  // implemented in JavaScript on top of the browser's DOM.
  //
  // You can find some technical background for some of the code below
  // at http://marijnhaverbeke.nl/blog/#cm-internals .
  
  (function (mod) {
      if (typeof exports == "object" && typeof module == "object") // CommonJS
          module.exports = mod();
      else if (typeof define == "function" && define.amd) // AMD
          return define([], mod);
      else // Plain browser env
          this.CodeMirror = mod();
  })(function () {
      "use strict";
  
      // BROWSER SNIFFING
  
      // Kludges for bugs and behavior differences that can't be feature
      // detected are enabled based on userAgent etc sniffing.
  
      var gecko = /gecko\/\d/i.test(navigator.userAgent);
      var ie_upto10 = /MSIE \d/.test(navigator.userAgent);
      var ie_11up = /Trident\/(?:[7-9]|\d{2,})\..*rv:(\d+)/.exec(navigator.userAgent);
      var ie = ie_upto10 || ie_11up;
      var ie_version = ie && (ie_upto10 ? document.documentMode || 6 : ie_11up[1]);
      var webkit = /WebKit\//.test(navigator.userAgent);
      var qtwebkit = webkit && /Qt\/\d+\.\d+/.test(navigator.userAgent);
      var chrome = /Chrome\//.test(navigator.userAgent);
      var presto = /Opera\//.test(navigator.userAgent);
      var safari = /Apple Computer/.test(navigator.vendor);
      var mac_geMountainLion = /Mac OS X 1\d\D([8-9]|\d\d)\D/.test(navigator.userAgent);
      var phantom = /PhantomJS/.test(navigator.userAgent);
  
      var ios = /AppleWebKit/.test(navigator.userAgent) && /Mobile\/\w+/.test(navigator.userAgent);
      // This is woefully incomplete. Suggestions for alternative methods welcome.
      var mobile = ios || /Android|webOS|BlackBerry|Opera Mini|Opera Mobi|IEMobile/i.test(navigator.userAgent);
      var mac = ios || /Mac/.test(navigator.platform);
      var windows = /win/i.test(navigator.platform);
  
      var presto_version = presto && navigator.userAgent.match(/Version\/(\d*\.\d*)/);
      if (presto_version) presto_version = Number(presto_version[1]);
      if (presto_version && presto_version >= 15) {
          presto = false;
          webkit = true;
      }
      // Some browsers use the wrong event properties to signal cmd/ctrl on OS X
      var flipCtrlCmd = mac && (qtwebkit || presto && (presto_version == null || presto_version < 12.11));
      var captureRightClick = gecko || (ie && ie_version >= 9);
  
      // Optimize some code when these features are not used.
      var sawReadOnlySpans = false, sawCollapsedSpans = false;
  
      // EDITOR CONSTRUCTOR
  
      // A CodeMirror instance represents an editor. This is the object
      // that user code is usually dealing with.
  
      function CodeMirror(place, options) {
          if (!(this instanceof CodeMirror)) return new CodeMirror(place, options);
  
          this.options = options = options ? copyObj(options) : {};
          // Determine effective options based on given values and defaults.
          copyObj(defaults, options, false);
          setGuttersForLineNumbers(options);
  
          var doc = options.value;
          if (typeof doc == "string") doc = new Doc(doc, options.mode);
          this.doc = doc;
  
          var input = new CodeMirror.inputStyles[options.inputStyle](this);
          var display = this.display = new Display(place, doc, input);
          display.wrapper.CodeMirror = this;
          updateGutters(this);
          themeChanged(this);
          if (options.lineWrapping)
              this.display.wrapper.className += " CodeMirror-wrap";
          if (options.autofocus && !mobile) display.input.focus();
          initScrollbars(this);
  
          this.state = {
              keyMaps: [],  // stores maps added by addKeyMap
              overlays: [], // highlighting overlays, as added by addOverlay
              modeGen: 0,   // bumped when mode/overlay changes, used to invalidate highlighting info
              overwrite: false, focused: false,
              suppressEdits: false, // used to disable editing during key handlers when in readOnly mode
              pasteIncoming: false, cutIncoming: false, // help recognize paste/cut edits in input.poll
              draggingText: false,
              highlight: new Delayed(), // stores highlight worker timeout
              keySeq: null  // Unfinished key sequence
          };
  
          var cm = this;
  
          // Override magic textarea content restore that IE sometimes does
          // on our hidden textarea on reload
          if (ie && ie_version < 11) setTimeout(function () {
              cm.display.input.reset(true);
          }, 20);
  
          registerEventHandlers(this);
          ensureGlobalHandlers();
  
          startOperation(this);
          this.curOp.forceUpdate = true;
          attachDoc(this, doc);
  
          if ((options.autofocus && !mobile) || cm.hasFocus())
              setTimeout(bind(onFocus, this), 20);
          else
              onBlur(this);
  
          for (var opt in optionHandlers) if (optionHandlers.hasOwnProperty(opt))
              optionHandlers[opt](this, options[opt], Init);
          maybeUpdateLineNumberWidth(this);
          if (options.finishInit) options.finishInit(this);
          for (var i = 0; i < initHooks.length; ++i) initHooks[i](this);
          endOperation(this);
          // Suppress optimizelegibility in Webkit, since it breaks text
          // measuring on line wrapping boundaries.
          if (webkit && options.lineWrapping &&
              getComputedStyle(display.lineDiv).textRendering == "optimizelegibility")
              display.lineDiv.style.textRendering = "auto";
      }
  
      // DISPLAY CONSTRUCTOR
  
      // The display handles the DOM integration, both for input reading
      // and content drawing. It holds references to DOM nodes and
      // display-related state.
  
      function Display(place, doc, input) {
          var d = this;
          this.input = input;
  
          // Covers bottom-right square when both scrollbars are present.
          d.scrollbarFiller = elt("div", null, "CodeMirror-scrollbar-filler");
          d.scrollbarFiller.setAttribute("cm-not-content", "true");
          // Covers bottom of gutter when coverGutterNextToScrollbar is on
          // and h scrollbar is present.
          d.gutterFiller = elt("div", null, "CodeMirror-gutter-filler");
          d.gutterFiller.setAttribute("cm-not-content", "true");
          // Will contain the actual code, positioned to cover the viewport.
          d.lineDiv = elt("div", null, "CodeMirror-code");
          // Elements are added to these to represent selection and cursors.
          d.selectionDiv = elt("div", null, null, "position: relative; z-index: 1");
          d.cursorDiv = elt("div", null, "CodeMirror-cursors");
          // A visibility: hidden element used to find the size of things.
          d.measure = elt("div", null, "CodeMirror-measure");
          // When lines outside of the viewport are measured, they are drawn in this.
          d.lineMeasure = elt("div", null, "CodeMirror-measure");
          // Wraps everything that needs to exist inside the vertically-padded coordinate system
          d.lineSpace = elt("div", [d.measure, d.lineMeasure, d.selectionDiv, d.cursorDiv, d.lineDiv],
              null, "position: relative; outline: none");
          // Moved around its parent to cover visible view.
          d.mover = elt("div", [elt("div", [d.lineSpace], "CodeMirror-lines")], null, "position: relative");
          // Set to the height of the document, allowing scrolling.
          d.sizer = elt("div", [d.mover], "CodeMirror-sizer");
          d.sizerWidth = null;
          // Behavior of elts with overflow: auto and padding is
          // inconsistent across browsers. This is used to ensure the
          // scrollable area is big enough.
          d.heightForcer = elt("div", null, null, "position: absolute; height: " + scrollerGap + "px; width: 1px;");
          // Will contain the gutters, if any.
          d.gutters = elt("div", null, "CodeMirror-gutters");
          d.lineGutter = null;
          // Actual scrollable element.
          d.scroller = elt("div", [d.sizer, d.heightForcer, d.gutters], "CodeMirror-scroll");
          d.scroller.setAttribute("tabIndex", "-1");
          // The element in which the editor lives.
          d.wrapper = elt("div", [d.scrollbarFiller, d.gutterFiller, d.scroller], "CodeMirror");
  
          // Work around IE7 z-index bug (not perfect, hence IE7 not really being supported)
          if (ie && ie_version < 8) {
              d.gutters.style.zIndex = -1;
              d.scroller.style.paddingRight = 0;
          }
          if (!webkit && !(gecko && mobile)) d.scroller.draggable = true;
  
          if (place) {
              if (place.appendChild) place.appendChild(d.wrapper);
              else place(d.wrapper);
          }
  
          // Current rendered range (may be bigger than the view window).
          d.viewFrom = d.viewTo = doc.first;
          d.reportedViewFrom = d.reportedViewTo = doc.first;
          // Information about the rendered lines.
          d.view = [];
          d.renderedView = null;
          // Holds info about a single rendered line when it was rendered
          // for measurement, while not in view.
          d.externalMeasured = null;
          // Empty space (in pixels) above the view
          d.viewOffset = 0;
          d.lastWrapHeight = d.lastWrapWidth = 0;
          d.updateLineNumbers = null;
  
          d.nativeBarWidth = d.barHeight = d.barWidth = 0;
          d.scrollbarsClipped = false;
  
          // Used to only resize the line number gutter when necessary (when
          // the amount of lines crosses a boundary that makes its width change)
          d.lineNumWidth = d.lineNumInnerWidth = d.lineNumChars = null;
          // Set to true when a non-horizontal-scrolling line widget is
          // added. As an optimization, line widget aligning is skipped when
          // this is false.
          d.alignWidgets = false;
  
          d.cachedCharWidth = d.cachedTextHeight = d.cachedPaddingH = null;
  
          // Tracks the maximum line length so that the horizontal scrollbar
          // can be kept static when scrolling.
          d.maxLine = null;
          d.maxLineLength = 0;
          d.maxLineChanged = false;
  
          // Used for measuring wheel scrolling granularity
          d.wheelDX = d.wheelDY = d.wheelStartX = d.wheelStartY = null;
  
          // True when shift is held down.
          d.shift = false;
  
          // Used to track whether anything happened since the context menu
          // was opened.
          d.selForContextMenu = null;
  
          d.activeTouch = null;
  
          input.init(d);
      }
  
      // STATE UPDATES
  
      // Used to get the editor into a consistent state again when options change.
  
      function loadMode(cm) {
          cm.doc.mode = CodeMirror.getMode(cm.options, cm.doc.modeOption);
          resetModeState(cm);
      }
  
      function resetModeState(cm) {
          cm.doc.iter(function (line) {
              if (line.stateAfter) line.stateAfter = null;
              if (line.styles) line.styles = null;
          });
          cm.doc.frontier = cm.doc.first;
          startWorker(cm, 100);
          cm.state.modeGen++;
          if (cm.curOp) regChange(cm);
      }
  
      function wrappingChanged(cm) {
          if (cm.options.lineWrapping) {
              addClass(cm.display.wrapper, "CodeMirror-wrap");
              cm.display.sizer.style.minWidth = "";
              cm.display.sizerWidth = null;
          } else {
              rmClass(cm.display.wrapper, "CodeMirror-wrap");
              findMaxLine(cm);
          }
          estimateLineHeights(cm);
          regChange(cm);
          clearCaches(cm);
          setTimeout(function () {
              updateScrollbars(cm);
          }, 100);
      }
  
      // Returns a function that estimates the height of a line, to use as
      // first approximation until the line becomes visible (and is thus
      // properly measurable).
      function estimateHeight(cm) {
          var th = textHeight(cm.display), wrapping = cm.options.lineWrapping;
          var perLine = wrapping && Math.max(5, cm.display.scroller.clientWidth / charWidth(cm.display) - 3);
          return function (line) {
              if (lineIsHidden(cm.doc, line)) return 0;
  
              var widgetsHeight = 0;
              if (line.widgets) for (var i = 0; i < line.widgets.length; i++) {
                  if (line.widgets[i].height) widgetsHeight += line.widgets[i].height;
              }
  
              if (wrapping)
                  return widgetsHeight + (Math.ceil(line.text.length / perLine) || 1) * th;
              else
                  return widgetsHeight + th;
          };
      }
  
      function estimateLineHeights(cm) {
          var doc = cm.doc, est = estimateHeight(cm);
          doc.iter(function (line) {
              var estHeight = est(line);
              if (estHeight != line.height) updateLineHeight(line, estHeight);
          });
      }
  
      function themeChanged(cm) {
          cm.display.wrapper.className = cm.display.wrapper.className.replace(/\s*cm-s-\S+/g, "") +
              cm.options.theme.replace(/(^|\s)\s*/g, " cm-s-");
          clearCaches(cm);
      }
  
      function guttersChanged(cm) {
          updateGutters(cm);
          regChange(cm);
          setTimeout(function () {
              alignHorizontally(cm);
          }, 20);
      }
  
      // Rebuild the gutter elements, ensure the margin to the left of the
      // code matches their width.
      function updateGutters(cm) {
          var gutters = cm.display.gutters, specs = cm.options.gutters;
          removeChildren(gutters);
          for (var i = 0; i < specs.length; ++i) {
              var gutterClass = specs[i];
              var gElt = gutters.appendChild(elt("div", null, "CodeMirror-gutter " + gutterClass));
              if (gutterClass == "CodeMirror-linenumbers") {
                  cm.display.lineGutter = gElt;
                  gElt.style.width = (cm.display.lineNumWidth || 1) + "px";
              }
          }
          gutters.style.display = i ? "" : "none";
          updateGutterSpace(cm);
      }
  
      function updateGutterSpace(cm) {
          var width = cm.display.gutters.offsetWidth;
          cm.display.sizer.style.marginLeft = width + "px";
      }
  
      // Compute the character length of a line, taking into account
      // collapsed ranges (see markText) that might hide parts, and join
      // other lines onto it.
      function lineLength(line) {
          if (line.height == 0) return 0;
          var len = line.text.length, merged, cur = line;
          while (merged = collapsedSpanAtStart(cur)) {
              var found = merged.find(0, true);
              cur = found.from.line;
              len += found.from.ch - found.to.ch;
          }
          cur = line;
          while (merged = collapsedSpanAtEnd(cur)) {
              var found = merged.find(0, true);
              len -= cur.text.length - found.from.ch;
              cur = found.to.line;
              len += cur.text.length - found.to.ch;
          }
          return len;
      }
  
      // Find the longest line in the document.
      function findMaxLine(cm) {
          var d = cm.display, doc = cm.doc;
          d.maxLine = getLine(doc, doc.first);
          d.maxLineLength = lineLength(d.maxLine);
          d.maxLineChanged = true;
          doc.iter(function (line) {
              var len = lineLength(line);
              if (len > d.maxLineLength) {
                  d.maxLineLength = len;
                  d.maxLine = line;
              }
          });
      }
  
      // Make sure the gutters options contains the element
      // "CodeMirror-linenumbers" when the lineNumbers option is true.
      function setGuttersForLineNumbers(options) {
          var found = indexOf(options.gutters, "CodeMirror-linenumbers");
          if (found == -1 && options.lineNumbers) {
              options.gutters = options.gutters.concat(["CodeMirror-linenumbers"]);
          } else if (found > -1 && !options.lineNumbers) {
              options.gutters = options.gutters.slice(0);
              options.gutters.splice(found, 1);
          }
      }
  
      // SCROLLBARS
  
      // Prepare DOM reads needed to update the scrollbars. Done in one
      // shot to minimize update/measure roundtrips.
      function measureForScrollbars(cm) {
          var d = cm.display, gutterW = d.gutters.offsetWidth;
          var docH = Math.round(cm.doc.height + paddingVert(cm.display));
          return {
              clientHeight: d.scroller.clientHeight,
              viewHeight: d.wrapper.clientHeight,
              scrollWidth: d.scroller.scrollWidth, clientWidth: d.scroller.clientWidth,
              viewWidth: d.wrapper.clientWidth,
              barLeft: cm.options.fixedGutter ? gutterW : 0,
              docHeight: docH,
              scrollHeight: docH + scrollGap(cm) + d.barHeight,
              nativeBarWidth: d.nativeBarWidth,
              gutterWidth: gutterW
          };
      }
  
      function NativeScrollbars(place, scroll, cm) {
          this.cm = cm;
          var vert = this.vert = elt("div", [elt("div", null, null, "min-width: 1px")], "CodeMirror-vscrollbar");
          var horiz = this.horiz = elt("div", [elt("div", null, null, "height: 100%; min-height: 1px")], "CodeMirror-hscrollbar");
          place(vert);
          place(horiz);
  
          on(vert, "scroll", function () {
              if (vert.clientHeight) scroll(vert.scrollTop, "vertical");
          });
          on(horiz, "scroll", function () {
              if (horiz.clientWidth) scroll(horiz.scrollLeft, "horizontal");
          });
  
          this.checkedOverlay = false;
          // Need to set a minimum width to see the scrollbar on IE7 (but must not set it on IE8).
          if (ie && ie_version < 8) this.horiz.style.minHeight = this.vert.style.minWidth = "18px";
      }
  
      NativeScrollbars.prototype = copyObj({
          update: function (measure) {
              var needsH = measure.scrollWidth > measure.clientWidth + 1;
              var needsV = measure.scrollHeight > measure.clientHeight + 1;
              var sWidth = measure.nativeBarWidth;
  
              if (needsV) {
                  this.vert.style.display = "block";
                  this.vert.style.bottom = needsH ? sWidth + "px" : "0";
                  var totalHeight = measure.viewHeight - (needsH ? sWidth : 0);
                  // A bug in IE8 can cause this value to be negative, so guard it.
                  this.vert.firstChild.style.height =
                      Math.max(0, measure.scrollHeight - measure.clientHeight + totalHeight) + "px";
              } else {
                  this.vert.style.display = "";
                  this.vert.firstChild.style.height = "0";
              }
  
              if (needsH) {
                  this.horiz.style.display = "block";
                  this.horiz.style.right = needsV ? sWidth + "px" : "0";
                  this.horiz.style.left = measure.barLeft + "px";
                  var totalWidth = measure.viewWidth - measure.barLeft - (needsV ? sWidth : 0);
                  this.horiz.firstChild.style.width =
                      (measure.scrollWidth - measure.clientWidth + totalWidth) + "px";
              } else {
                  this.horiz.style.display = "";
                  this.horiz.firstChild.style.width = "0";
              }
  
              if (!this.checkedOverlay && measure.clientHeight > 0) {
                  if (sWidth == 0) this.overlayHack();
                  this.checkedOverlay = true;
              }
  
              return {right: needsV ? sWidth : 0, bottom: needsH ? sWidth : 0};
          },
          setScrollLeft: function (pos) {
              if (this.horiz.scrollLeft != pos) this.horiz.scrollLeft = pos;
          },
          setScrollTop: function (pos) {
              if (this.vert.scrollTop != pos) this.vert.scrollTop = pos;
          },
          overlayHack: function () {
              var w = mac && !mac_geMountainLion ? "12px" : "18px";
              this.horiz.style.minHeight = this.vert.style.minWidth = w;
              var self = this;
              var barMouseDown = function (e) {
                  if (e_target(e) != self.vert && e_target(e) != self.horiz)
                      operation(self.cm, onMouseDown)(e);
              };
              on(this.vert, "mousedown", barMouseDown);
              on(this.horiz, "mousedown", barMouseDown);
          },
          clear: function () {
              var parent = this.horiz.parentNode;
              parent.removeChild(this.horiz);
              parent.removeChild(this.vert);
          }
      }, NativeScrollbars.prototype);
  
      function NullScrollbars() {
      }
  
      NullScrollbars.prototype = copyObj({
          update: function () {
              return {bottom: 0, right: 0};
          },
          setScrollLeft: function () {
          },
          setScrollTop: function () {
          },
          clear: function () {
          }
      }, NullScrollbars.prototype);
  
      CodeMirror.scrollbarModel = {"native": NativeScrollbars, "null": NullScrollbars};
  
      function initScrollbars(cm) {
          if (cm.display.scrollbars) {
              cm.display.scrollbars.clear();
              if (cm.display.scrollbars.addClass)
                  rmClass(cm.display.wrapper, cm.display.scrollbars.addClass);
          }
  
          cm.display.scrollbars = new CodeMirror.scrollbarModel[cm.options.scrollbarStyle](function (node) {
              cm.display.wrapper.insertBefore(node, cm.display.scrollbarFiller);
              // Prevent clicks in the scrollbars from killing focus
              on(node, "mousedown", function () {
                  if (cm.state.focused) setTimeout(function () {
                      cm.display.input.focus();
                  }, 0);
              });
              node.setAttribute("cm-not-content", "true");
          }, function (pos, axis) {
              if (axis == "horizontal") setScrollLeft(cm, pos);
              else setScrollTop(cm, pos);
          }, cm);
          if (cm.display.scrollbars.addClass)
              addClass(cm.display.wrapper, cm.display.scrollbars.addClass);
      }
  
      function updateScrollbars(cm, measure) {
          if (!measure) measure = measureForScrollbars(cm);
          var startWidth = cm.display.barWidth, startHeight = cm.display.barHeight;
          updateScrollbarsInner(cm, measure);
          for (var i = 0; i < 4 && startWidth != cm.display.barWidth || startHeight != cm.display.barHeight; i++) {
              if (startWidth != cm.display.barWidth && cm.options.lineWrapping)
                  updateHeightsInViewport(cm);
              updateScrollbarsInner(cm, measureForScrollbars(cm));
              startWidth = cm.display.barWidth;
              startHeight = cm.display.barHeight;
          }
      }
  
      // Re-synchronize the fake scrollbars with the actual size of the
      // content.
      function updateScrollbarsInner(cm, measure) {
          var d = cm.display;
          var sizes = d.scrollbars.update(measure);
  
          d.sizer.style.paddingRight = (d.barWidth = sizes.right) + "px";
          d.sizer.style.paddingBottom = (d.barHeight = sizes.bottom) + "px";
  
          if (sizes.right && sizes.bottom) {
              d.scrollbarFiller.style.display = "block";
              d.scrollbarFiller.style.height = sizes.bottom + "px";
              d.scrollbarFiller.style.width = sizes.right + "px";
          } else d.scrollbarFiller.style.display = "";
          if (sizes.bottom && cm.options.coverGutterNextToScrollbar && cm.options.fixedGutter) {
              d.gutterFiller.style.display = "block";
              d.gutterFiller.style.height = sizes.bottom + "px";
              d.gutterFiller.style.width = measure.gutterWidth + "px";
          } else d.gutterFiller.style.display = "";
      }
  
      // Compute the lines that are visible in a given viewport (defaults
      // the the current scroll position). viewport may contain top,
      // height, and ensure (see op.scrollToPos) properties.
      function visibleLines(display, doc, viewport) {
          var top = viewport && viewport.top != null ? Math.max(0, viewport.top) : display.scroller.scrollTop;
          top = Math.floor(top - paddingTop(display));
          var bottom = viewport && viewport.bottom != null ? viewport.bottom : top + display.wrapper.clientHeight;
  
          var from = lineAtHeight(doc, top), to = lineAtHeight(doc, bottom);
          // Ensure is a {from: {line, ch}, to: {line, ch}} object, and
          // forces those lines into the viewport (if possible).
          if (viewport && viewport.ensure) {
              var ensureFrom = viewport.ensure.from.line, ensureTo = viewport.ensure.to.line;
              if (ensureFrom < from) {
                  from = ensureFrom;
                  to = lineAtHeight(doc, heightAtLine(getLine(doc, ensureFrom)) + display.wrapper.clientHeight);
              } else if (Math.min(ensureTo, doc.lastLine()) >= to) {
                  from = lineAtHeight(doc, heightAtLine(getLine(doc, ensureTo)) - display.wrapper.clientHeight);
                  to = ensureTo;
              }
          }
          return {from: from, to: Math.max(to, from + 1)};
      }
  
      // LINE NUMBERS
  
      // Re-align line numbers and gutter marks to compensate for
      // horizontal scrolling.
      function alignHorizontally(cm) {
          var display = cm.display, view = display.view;
          if (!display.alignWidgets && (!display.gutters.firstChild || !cm.options.fixedGutter)) return;
          var comp = compensateForHScroll(display) - display.scroller.scrollLeft + cm.doc.scrollLeft;
          var gutterW = display.gutters.offsetWidth, left = comp + "px";
          for (var i = 0; i < view.length; i++) if (!view[i].hidden) {
              if (cm.options.fixedGutter && view[i].gutter)
                  view[i].gutter.style.left = left;
              var align = view[i].alignable;
              if (align) for (var j = 0; j < align.length; j++)
                  align[j].style.left = left;
          }
          if (cm.options.fixedGutter)
              display.gutters.style.left = (comp + gutterW) + "px";
      }
  
      // Used to ensure that the line number gutter is still the right
      // size for the current document size. Returns true when an update
      // is needed.
      function maybeUpdateLineNumberWidth(cm) {
          if (!cm.options.lineNumbers) return false;
          var doc = cm.doc, last = lineNumberFor(cm.options, doc.first + doc.size - 1), display = cm.display;
          if (last.length != display.lineNumChars) {
              var test = display.measure.appendChild(elt("div", [elt("div", last)],
                  "CodeMirror-linenumber CodeMirror-gutter-elt"));
              var innerW = test.firstChild.offsetWidth, padding = test.offsetWidth - innerW;
              display.lineGutter.style.width = "";
              display.lineNumInnerWidth = Math.max(innerW, display.lineGutter.offsetWidth - padding);
              display.lineNumWidth = display.lineNumInnerWidth + padding;
              display.lineNumChars = display.lineNumInnerWidth ? last.length : -1;
              display.lineGutter.style.width = display.lineNumWidth + "px";
              updateGutterSpace(cm);
              return true;
          }
          return false;
      }
  
      function lineNumberFor(options, i) {
          return String(options.lineNumberFormatter(i + options.firstLineNumber));
      }
  
      // Computes display.scroller.scrollLeft + display.gutters.offsetWidth,
      // but using getBoundingClientRect to get a sub-pixel-accurate
      // result.
      function compensateForHScroll(display) {
          return display.scroller.getBoundingClientRect().left - display.sizer.getBoundingClientRect().left;
      }
  
      // DISPLAY DRAWING
  
      function DisplayUpdate(cm, viewport, force) {
          var display = cm.display;
  
          this.viewport = viewport;
          // Store some values that we'll need later (but don't want to force a relayout for)
          this.visible = visibleLines(display, cm.doc, viewport);
          this.editorIsHidden = !display.wrapper.offsetWidth;
          this.wrapperHeight = display.wrapper.clientHeight;
          this.wrapperWidth = display.wrapper.clientWidth;
          this.oldDisplayWidth = displayWidth(cm);
          this.force = force;
          this.dims = getDimensions(cm);
          this.events = [];
      }
  
      DisplayUpdate.prototype.signal = function (emitter, type) {
          if (hasHandler(emitter, type))
              this.events.push(arguments);
      };
      DisplayUpdate.prototype.finish = function () {
          for (var i = 0; i < this.events.length; i++)
              signal.apply(null, this.events[i]);
      };
  
      function maybeClipScrollbars(cm) {
          var display = cm.display;
          if (!display.scrollbarsClipped && display.scroller.offsetWidth) {
              display.nativeBarWidth = display.scroller.offsetWidth - display.scroller.clientWidth;
              display.heightForcer.style.height = scrollGap(cm) + "px";
              display.sizer.style.marginBottom = -display.nativeBarWidth + "px";
              display.sizer.style.borderRightWidth = scrollGap(cm) + "px";
              display.scrollbarsClipped = true;
          }
      }
  
      // Does the actual updating of the line display. Bails out
      // (returning false) when there is nothing to be done and forced is
      // false.
      function updateDisplayIfNeeded(cm, update) {
          var display = cm.display, doc = cm.doc;
  
          if (update.editorIsHidden) {
              resetView(cm);
              return false;
          }
  
          // Bail out if the visible area is already rendered and nothing changed.
          if (!update.force &&
              update.visible.from >= display.viewFrom && update.visible.to <= display.viewTo &&
              (display.updateLineNumbers == null || display.updateLineNumbers >= display.viewTo) &&
              display.renderedView == display.view && countDirtyView(cm) == 0)
              return false;
  
          if (maybeUpdateLineNumberWidth(cm)) {
              resetView(cm);
              update.dims = getDimensions(cm);
          }
  
          // Compute a suitable new viewport (from & to)
          var end = doc.first + doc.size;
          var from = Math.max(update.visible.from - cm.options.viewportMargin, doc.first);
          var to = Math.min(end, update.visible.to + cm.options.viewportMargin);
          if (display.viewFrom < from && from - display.viewFrom < 20) from = Math.max(doc.first, display.viewFrom);
          if (display.viewTo > to && display.viewTo - to < 20) to = Math.min(end, display.viewTo);
          if (sawCollapsedSpans) {
              from = visualLineNo(cm.doc, from);
              to = visualLineEndNo(cm.doc, to);
          }
  
          var different = from != display.viewFrom || to != display.viewTo ||
              display.lastWrapHeight != update.wrapperHeight || display.lastWrapWidth != update.wrapperWidth;
          adjustView(cm, from, to);
  
          display.viewOffset = heightAtLine(getLine(cm.doc, display.viewFrom));
          // Position the mover div to align with the current scroll position
          cm.display.mover.style.top = display.viewOffset + "px";
  
          var toUpdate = countDirtyView(cm);
          if (!different && toUpdate == 0 && !update.force && display.renderedView == display.view &&
              (display.updateLineNumbers == null || display.updateLineNumbers >= display.viewTo))
              return false;
  
          // For big changes, we hide the enclosing element during the
          // update, since that speeds up the operations on most browsers.
          var focused = activeElt();
          if (toUpdate > 4) display.lineDiv.style.display = "none";
          patchDisplay(cm, display.updateLineNumbers, update.dims);
          if (toUpdate > 4) display.lineDiv.style.display = "";
          display.renderedView = display.view;
          // There might have been a widget with a focused element that got
          // hidden or updated, if so re-focus it.
          if (focused && activeElt() != focused && focused.offsetHeight) focused.focus();
  
          // Prevent selection and cursors from interfering with the scroll
          // width and height.
          removeChildren(display.cursorDiv);
          removeChildren(display.selectionDiv);
          display.gutters.style.height = 0;
  
          if (different) {
              display.lastWrapHeight = update.wrapperHeight;
              display.lastWrapWidth = update.wrapperWidth;
              startWorker(cm, 400);
          }
  
          display.updateLineNumbers = null;
  
          return true;
      }
  
      function postUpdateDisplay(cm, update) {
          var force = update.force, viewport = update.viewport;
          for (var first = true; ; first = false) {
              if (first && cm.options.lineWrapping && update.oldDisplayWidth != displayWidth(cm)) {
                  force = true;
              } else {
                  force = false;
                  // Clip forced viewport to actual scrollable area.
                  if (viewport && viewport.top != null)
                      viewport = {top: Math.min(cm.doc.height + paddingVert(cm.display) - displayHeight(cm), viewport.top)};
                  // Updated line heights might result in the drawn area not
                  // actually covering the viewport. Keep looping until it does.
                  update.visible = visibleLines(cm.display, cm.doc, viewport);
                  if (update.visible.from >= cm.display.viewFrom && update.visible.to <= cm.display.viewTo)
                      break;
              }
              if (!updateDisplayIfNeeded(cm, update)) break;
              updateHeightsInViewport(cm);
              var barMeasure = measureForScrollbars(cm);
              updateSelection(cm);
              setDocumentHeight(cm, barMeasure);
              updateScrollbars(cm, barMeasure);
          }
  
          update.signal(cm, "update", cm);
          if (cm.display.viewFrom != cm.display.reportedViewFrom || cm.display.viewTo != cm.display.reportedViewTo) {
              update.signal(cm, "viewportChange", cm, cm.display.viewFrom, cm.display.viewTo);
              cm.display.reportedViewFrom = cm.display.viewFrom;
              cm.display.reportedViewTo = cm.display.viewTo;
          }
      }
  
      function updateDisplaySimple(cm, viewport) {
          var update = new DisplayUpdate(cm, viewport);
          if (updateDisplayIfNeeded(cm, update)) {
              updateHeightsInViewport(cm);
              postUpdateDisplay(cm, update);
              var barMeasure = measureForScrollbars(cm);
              updateSelection(cm);
              setDocumentHeight(cm, barMeasure);
              updateScrollbars(cm, barMeasure);
              update.finish();
          }
      }
  
      function setDocumentHeight(cm, measure) {
          cm.display.sizer.style.minHeight = measure.docHeight + "px";
          var total = measure.docHeight + cm.display.barHeight;
          cm.display.heightForcer.style.top = total + "px";
          cm.display.gutters.style.height = Math.max(total + scrollGap(cm), measure.clientHeight) + "px";
      }
  
      // Read the actual heights of the rendered lines, and update their
      // stored heights to match.
      function updateHeightsInViewport(cm) {
          var display = cm.display;
          var prevBottom = display.lineDiv.offsetTop;
          for (var i = 0; i < display.view.length; i++) {
              var cur = display.view[i], height;
              if (cur.hidden) continue;
              if (ie && ie_version < 8) {
                  var bot = cur.node.offsetTop + cur.node.offsetHeight;
                  height = bot - prevBottom;
                  prevBottom = bot;
              } else {
                  var box = cur.node.getBoundingClientRect();
                  height = box.bottom - box.top;
              }
              var diff = cur.line.height - height;
              if (height < 2) height = textHeight(display);
              if (diff > .001 || diff < -.001) {
                  updateLineHeight(cur.line, height);
                  updateWidgetHeight(cur.line);
                  if (cur.rest) for (var j = 0; j < cur.rest.length; j++)
                      updateWidgetHeight(cur.rest[j]);
              }
          }
      }
  
      // Read and store the height of line widgets associated with the
      // given line.
      function updateWidgetHeight(line) {
          if (line.widgets) for (var i = 0; i < line.widgets.length; ++i)
              line.widgets[i].height = line.widgets[i].node.offsetHeight;
      }
  
      // Do a bulk-read of the DOM positions and sizes needed to draw the
      // view, so that we don't interleave reading and writing to the DOM.
      function getDimensions(cm) {
          var d = cm.display, left = {}, width = {};
          var gutterLeft = d.gutters.clientLeft;
          for (var n = d.gutters.firstChild, i = 0; n; n = n.nextSibling, ++i) {
              left[cm.options.gutters[i]] = n.offsetLeft + n.clientLeft + gutterLeft;
              width[cm.options.gutters[i]] = n.clientWidth;
          }
          return {
              fixedPos: compensateForHScroll(d),
              gutterTotalWidth: d.gutters.offsetWidth,
              gutterLeft: left,
              gutterWidth: width,
              wrapperWidth: d.wrapper.clientWidth
          };
      }
  
      // Sync the actual display DOM structure with display.view, removing
      // nodes for lines that are no longer in view, and creating the ones
      // that are not there yet, and updating the ones that are out of
      // date.
      function patchDisplay(cm, updateNumbersFrom, dims) {
          var display = cm.display, lineNumbers = cm.options.lineNumbers;
          var container = display.lineDiv, cur = container.firstChild;
  
          function rm(node) {
              var next = node.nextSibling;
              // Works around a throw-scroll bug in OS X Webkit
              if (webkit && mac && cm.display.currentWheelTarget == node)
                  node.style.display = "none";
              else
                  node.parentNode.removeChild(node);
              return next;
          }
  
          var view = display.view, lineN = display.viewFrom;
          // Loop over the elements in the view, syncing cur (the DOM nodes
          // in display.lineDiv) with the view as we go.
          for (var i = 0; i < view.length; i++) {
              var lineView = view[i];
              if (lineView.hidden) {
              } else if (!lineView.node || lineView.node.parentNode != container) { // Not drawn yet
                  var node = buildLineElement(cm, lineView, lineN, dims);
                  container.insertBefore(node, cur);
              } else { // Already drawn
                  while (cur != lineView.node) cur = rm(cur);
                  var updateNumber = lineNumbers && updateNumbersFrom != null &&
                      updateNumbersFrom <= lineN && lineView.lineNumber;
                  if (lineView.changes) {
                      if (indexOf(lineView.changes, "gutter") > -1) updateNumber = false;
                      updateLineForChanges(cm, lineView, lineN, dims);
                  }
                  if (updateNumber) {
                      removeChildren(lineView.lineNumber);
                      lineView.lineNumber.appendChild(document.createTextNode(lineNumberFor(cm.options, lineN)));
                  }
                  cur = lineView.node.nextSibling;
              }
              lineN += lineView.size;
          }
          while (cur) cur = rm(cur);
      }
  
      // When an aspect of a line changes, a string is added to
      // lineView.changes. This updates the relevant part of the line's
      // DOM structure.
      function updateLineForChanges(cm, lineView, lineN, dims) {
          for (var j = 0; j < lineView.changes.length; j++) {
              var type = lineView.changes[j];
              if (type == "text") updateLineText(cm, lineView);
              else if (type == "gutter") updateLineGutter(cm, lineView, lineN, dims);
              else if (type == "class") updateLineClasses(lineView);
              else if (type == "widget") updateLineWidgets(cm, lineView, dims);
          }
          lineView.changes = null;
      }
  
      // Lines with gutter elements, widgets or a background class need to
      // be wrapped, and have the extra elements added to the wrapper div
      function ensureLineWrapped(lineView) {
          if (lineView.node == lineView.text) {
              lineView.node = elt("div", null, null, "position: relative");
              if (lineView.text.parentNode)
                  lineView.text.parentNode.replaceChild(lineView.node, lineView.text);
              lineView.node.appendChild(lineView.text);
              if (ie && ie_version < 8) lineView.node.style.zIndex = 2;
          }
          return lineView.node;
      }
  
      function updateLineBackground(lineView) {
          var cls = lineView.bgClass ? lineView.bgClass + " " + (lineView.line.bgClass || "") : lineView.line.bgClass;
          if (cls) cls += " CodeMirror-linebackground";
          if (lineView.background) {
              if (cls) lineView.background.className = cls;
              else {
                  lineView.background.parentNode.removeChild(lineView.background);
                  lineView.background = null;
              }
          } else if (cls) {
              var wrap = ensureLineWrapped(lineView);
              lineView.background = wrap.insertBefore(elt("div", null, cls), wrap.firstChild);
          }
      }
  
      // Wrapper around buildLineContent which will reuse the structure
      // in display.externalMeasured when possible.
      function getLineContent(cm, lineView) {
          var ext = cm.display.externalMeasured;
          if (ext && ext.line == lineView.line) {
              cm.display.externalMeasured = null;
              lineView.measure = ext.measure;
              return ext.built;
          }
          return buildLineContent(cm, lineView);
      }
  
      // Redraw the line's text. Interacts with the background and text
      // classes because the mode may output tokens that influence these
      // classes.
      function updateLineText(cm, lineView) {
          var cls = lineView.text.className;
          var built = getLineContent(cm, lineView);
          if (lineView.text == lineView.node) lineView.node = built.pre;
          lineView.text.parentNode.replaceChild(built.pre, lineView.text);
          lineView.text = built.pre;
          if (built.bgClass != lineView.bgClass || built.textClass != lineView.textClass) {
              lineView.bgClass = built.bgClass;
              lineView.textClass = built.textClass;
              updateLineClasses(lineView);
          } else if (cls) {
              lineView.text.className = cls;
          }
      }
  
      function updateLineClasses(lineView) {
          updateLineBackground(lineView);
          if (lineView.line.wrapClass)
              ensureLineWrapped(lineView).className = lineView.line.wrapClass;
          else if (lineView.node != lineView.text)
              lineView.node.className = "";
          var textClass = lineView.textClass ? lineView.textClass + " " + (lineView.line.textClass || "") : lineView.line.textClass;
          lineView.text.className = textClass || "";
      }
  
      function updateLineGutter(cm, lineView, lineN, dims) {
          if (lineView.gutter) {
              lineView.node.removeChild(lineView.gutter);
              lineView.gutter = null;
          }
          var markers = lineView.line.gutterMarkers;
          if (cm.options.lineNumbers || markers) {
              var wrap = ensureLineWrapped(lineView);
              var gutterWrap = lineView.gutter = elt("div", null, "CodeMirror-gutter-wrapper", "left: " +
                  (cm.options.fixedGutter ? dims.fixedPos : -dims.gutterTotalWidth) +
                  "px; width: " + dims.gutterTotalWidth + "px");
              cm.display.input.setUneditable(gutterWrap);
              wrap.insertBefore(gutterWrap, lineView.text);
              if (lineView.line.gutterClass)
                  gutterWrap.className += " " + lineView.line.gutterClass;
              if (cm.options.lineNumbers && (!markers || !markers["CodeMirror-linenumbers"]))
                  lineView.lineNumber = gutterWrap.appendChild(
                      elt("div", lineNumberFor(cm.options, lineN),
                          "CodeMirror-linenumber CodeMirror-gutter-elt",
                          "left: " + dims.gutterLeft["CodeMirror-linenumbers"] + "px; width: "
                          + cm.display.lineNumInnerWidth + "px"));
              if (markers) for (var k = 0; k < cm.options.gutters.length; ++k) {
                  var id = cm.options.gutters[k], found = markers.hasOwnProperty(id) && markers[id];
                  if (found)
                      gutterWrap.appendChild(elt("div", [found], "CodeMirror-gutter-elt", "left: " +
                          dims.gutterLeft[id] + "px; width: " + dims.gutterWidth[id] + "px"));
              }
          }
      }
  
      function updateLineWidgets(cm, lineView, dims) {
          if (lineView.alignable) lineView.alignable = null;
          for (var node = lineView.node.firstChild, next; node; node = next) {
              var next = node.nextSibling;
              if (node.className == "CodeMirror-linewidget")
                  lineView.node.removeChild(node);
          }
          insertLineWidgets(cm, lineView, dims);
      }
  
      // Build a line's DOM representation from scratch
      function buildLineElement(cm, lineView, lineN, dims) {
          var built = getLineContent(cm, lineView);
          lineView.text = lineView.node = built.pre;
          if (built.bgClass) lineView.bgClass = built.bgClass;
          if (built.textClass) lineView.textClass = built.textClass;
  
          updateLineClasses(lineView);
          updateLineGutter(cm, lineView, lineN, dims);
          insertLineWidgets(cm, lineView, dims);
          return lineView.node;
      }
  
      // A lineView may contain multiple logical lines (when merged by
      // collapsed spans). The widgets for all of them need to be drawn.
      function insertLineWidgets(cm, lineView, dims) {
          insertLineWidgetsFor(cm, lineView.line, lineView, dims, true);
          if (lineView.rest) for (var i = 0; i < lineView.rest.length; i++)
              insertLineWidgetsFor(cm, lineView.rest[i], lineView, dims, false);
      }
  
      function insertLineWidgetsFor(cm, line, lineView, dims, allowAbove) {
          if (!line.widgets) return;
          var wrap = ensureLineWrapped(lineView);
          for (var i = 0, ws = line.widgets; i < ws.length; ++i) {
              var widget = ws[i], node = elt("div", [widget.node], "CodeMirror-linewidget");
              if (!widget.handleMouseEvents) node.setAttribute("cm-ignore-events", "true");
              positionLineWidget(widget, node, lineView, dims);
              cm.display.input.setUneditable(node);
              if (allowAbove && widget.above)
                  wrap.insertBefore(node, lineView.gutter || lineView.text);
              else
                  wrap.appendChild(node);
              signalLater(widget, "redraw");
          }
      }
  
      function positionLineWidget(widget, node, lineView, dims) {
          if (widget.noHScroll) {
              (lineView.alignable || (lineView.alignable = [])).push(node);
              var width = dims.wrapperWidth;
              node.style.left = dims.fixedPos + "px";
              if (!widget.coverGutter) {
                  width -= dims.gutterTotalWidth;
                  node.style.paddingLeft = dims.gutterTotalWidth + "px";
              }
              node.style.width = width + "px";
          }
          if (widget.coverGutter) {
              node.style.zIndex = 5;
              node.style.position = "relative";
              if (!widget.noHScroll) node.style.marginLeft = -dims.gutterTotalWidth + "px";
          }
      }
  
      // POSITION OBJECT
  
      // A Pos instance represents a position within the text.
      var Pos = CodeMirror.Pos = function (line, ch) {
          if (!(this instanceof Pos)) return new Pos(line, ch);
          this.line = line;
          this.ch = ch;
      };
  
      // Compare two positions, return 0 if they are the same, a negative
      // number when a is less, and a positive number otherwise.
      var cmp = CodeMirror.cmpPos = function (a, b) {
          return a.line - b.line || a.ch - b.ch;
      };
  
      function copyPos(x) {
          return Pos(x.line, x.ch);
      }
  
      function maxPos(a, b) {
          return cmp(a, b) < 0 ? b : a;
      }
  
      function minPos(a, b) {
          return cmp(a, b) < 0 ? a : b;
      }
  
      // INPUT HANDLING
  
      function ensureFocus(cm) {
          if (!cm.state.focused) {
              cm.display.input.focus();
              onFocus(cm);
          }
      }
  
      function isReadOnly(cm) {
          return cm.options.readOnly || cm.doc.cantEdit;
      }
  
      // This will be set to an array of strings when copying, so that,
      // when pasting, we know what kind of selections the copied text
      // was made out of.
      var lastCopied = null;
  
      function applyTextInput(cm, inserted, deleted, sel) {
          var doc = cm.doc;
          cm.display.shift = false;
          if (!sel) sel = doc.sel;
  
          var textLines = splitLines(inserted), multiPaste = null;
          // When pasing N lines into N selections, insert one line per selection
          if (cm.state.pasteIncoming && sel.ranges.length > 1) {
              if (lastCopied && lastCopied.join("\n") == inserted)
                  multiPaste = sel.ranges.length % lastCopied.length == 0 && map(lastCopied, splitLines);
              else if (textLines.length == sel.ranges.length)
                  multiPaste = map(textLines, function (l) {
                      return [l];
                  });
          }
  
          // Normal behavior is to insert the new text into every selection
          for (var i = sel.ranges.length - 1; i >= 0; i--) {
              var range = sel.ranges[i];
              var from = range.from(), to = range.to();
              if (range.empty()) {
                  if (deleted && deleted > 0) // Handle deletion
                      from = Pos(from.line, from.ch - deleted);
                  else if (cm.state.overwrite && !cm.state.pasteIncoming) // Handle overwrite
                      to = Pos(to.line, Math.min(getLine(doc, to.line).text.length, to.ch + lst(textLines).length));
              }
              var updateInput = cm.curOp.updateInput;
              var changeEvent = {
                  from: from, to: to, text: multiPaste ? multiPaste[i % multiPaste.length] : textLines,
                  origin: cm.state.pasteIncoming ? "paste" : cm.state.cutIncoming ? "cut" : "+input"
              };
              makeChange(cm.doc, changeEvent);
              signalLater(cm, "inputRead", cm, changeEvent);
              // When an 'electric' character is inserted, immediately trigger a reindent
              if (inserted && !cm.state.pasteIncoming && cm.options.electricChars &&
                  cm.options.smartIndent && range.head.ch < 100 &&
                  (!i || sel.ranges[i - 1].head.line != range.head.line)) {
                  var mode = cm.getModeAt(range.head);
                  var end = changeEnd(changeEvent);
                  if (mode.electricChars) {
                      for (var j = 0; j < mode.electricChars.length; j++)
                          if (inserted.indexOf(mode.electricChars.charAt(j)) > -1) {
                              indentLine(cm, end.line, "smart");
                              break;
                          }
                  } else if (mode.electricInput) {
                      if (mode.electricInput.test(getLine(doc, end.line).text.slice(0, end.ch)))
                          indentLine(cm, end.line, "smart");
                  }
              }
          }
          ensureCursorVisible(cm);
          cm.curOp.updateInput = updateInput;
          cm.curOp.typing = true;
          cm.state.pasteIncoming = cm.state.cutIncoming = false;
      }
  
      function copyableRanges(cm) {
          var text = [], ranges = [];
          for (var i = 0; i < cm.doc.sel.ranges.length; i++) {
              var line = cm.doc.sel.ranges[i].head.line;
              var lineRange = {anchor: Pos(line, 0), head: Pos(line + 1, 0)};
              ranges.push(lineRange);
              text.push(cm.getRange(lineRange.anchor, lineRange.head));
          }
          return {text: text, ranges: ranges};
      }
  
      function disableBrowserMagic(field) {
          field.setAttribute("autocorrect", "off");
          field.setAttribute("autocapitalize", "off");
          field.setAttribute("spellcheck", "false");
      }
  
      // TEXTAREA INPUT STYLE
  
      function TextareaInput(cm) {
          this.cm = cm;
          // See input.poll and input.reset
          this.prevInput = "";
  
          // Flag that indicates whether we expect input to appear real soon
          // now (after some event like 'keypress' or 'input') and are
          // polling intensively.
          this.pollingFast = false;
          // Self-resetting timeout for the poller
          this.polling = new Delayed();
          // Tracks when input.reset has punted to just putting a short
          // string into the textarea instead of the full selection.
          this.inaccurateSelection = false;
          // Used to work around IE issue with selection being forgotten when focus moves away from textarea
          this.hasSelection = false;
      };
  
      function hiddenTextarea() {
          var te = elt("textarea", null, null, "position: absolute; padding: 0; width: 1px; height: 1em; outline: none");
          var div = elt("div", [te], null, "overflow: hidden; position: relative; width: 3px; height: 0px;");
          // The textarea is kept positioned near the cursor to prevent the
          // fact that it'll be scrolled into view on input from scrolling
          // our fake cursor out of view. On webkit, when wrap=off, paste is
          // very slow. So make the area wide instead.
          if (webkit) te.style.width = "1000px";
          else te.setAttribute("wrap", "off");
          // If border: 0; -- iOS fails to open keyboard (issue #1287)
          if (ios) te.style.border = "1px solid black";
          disableBrowserMagic(te);
          return div;
      }
  
      TextareaInput.prototype = copyObj({
          init: function (display) {
              var input = this, cm = this.cm;
  
              // Wraps and hides input textarea
              var div = this.wrapper = hiddenTextarea();
              // The semihidden textarea that is focused when the editor is
              // focused, and receives input.
              var te = this.textarea = div.firstChild;
              display.wrapper.insertBefore(div, display.wrapper.firstChild);
  
              // Needed to hide big blue blinking cursor on Mobile Safari (doesn't seem to work in iOS 8 anymore)
              if (ios) te.style.width = "0px";
  
              on(te, "input", function () {
                  if (ie && ie_version >= 9 && input.hasSelection) input.hasSelection = null;
                  input.poll();
              });
  
              on(te, "paste", function () {
                  // Workaround for webkit bug https://bugs.webkit.org/show_bug.cgi?id=90206
                  // Add a char to the end of textarea before paste occur so that
                  // selection doesn't span to the end of textarea.
                  if (webkit && !cm.state.fakedLastChar && !(new Date - cm.state.lastMiddleDown < 200)) {
                      var start = te.selectionStart, end = te.selectionEnd;
                      te.value += "$";
                      // The selection end needs to be set before the start, otherwise there
                      // can be an intermediate non-empty selection between the two, which
                      // can override the middle-click paste buffer on linux and cause the
                      // wrong thing to get pasted.
                      te.selectionEnd = end;
                      te.selectionStart = start;
                      cm.state.fakedLastChar = true;
                  }
                  cm.state.pasteIncoming = true;
                  input.fastPoll();
              });
  
              function prepareCopyCut(e) {
                  if (cm.somethingSelected()) {
                      lastCopied = cm.getSelections();
                      if (input.inaccurateSelection) {
                          input.prevInput = "";
                          input.inaccurateSelection = false;
                          te.value = lastCopied.join("\n");
                          selectInput(te);
                      }
                  } else {
                      var ranges = copyableRanges(cm);
                      lastCopied = ranges.text;
                      if (e.type == "cut") {
                          cm.setSelections(ranges.ranges, null, sel_dontScroll);
                      } else {
                          input.prevInput = "";
                          te.value = ranges.text.join("\n");
                          selectInput(te);
                      }
                  }
                  if (e.type == "cut") cm.state.cutIncoming = true;
              }
  
              on(te, "cut", prepareCopyCut);
              on(te, "copy", prepareCopyCut);
  
              on(display.scroller, "paste", function (e) {
                  if (eventInWidget(display, e)) return;
                  cm.state.pasteIncoming = true;
                  input.focus();
              });
  
              // Prevent normal selection in the editor (we handle our own)
              on(display.lineSpace, "selectstart", function (e) {
                  if (!eventInWidget(display, e)) e_preventDefault(e);
              });
          },
  
          prepareSelection: function () {
              // Redraw the selection and/or cursor
              var cm = this.cm, display = cm.display, doc = cm.doc;
              var result = prepareSelection(cm);
  
              // Move the hidden textarea near the cursor to prevent scrolling artifacts
              if (cm.options.moveInputWithCursor) {
                  var headPos = cursorCoords(cm, doc.sel.primary().head, "div");
                  var wrapOff = display.wrapper.getBoundingClientRect(),
                      lineOff = display.lineDiv.getBoundingClientRect();
                  result.teTop = Math.max(0, Math.min(display.wrapper.clientHeight - 10,
                      headPos.top + lineOff.top - wrapOff.top));
                  result.teLeft = Math.max(0, Math.min(display.wrapper.clientWidth - 10,
                      headPos.left + lineOff.left - wrapOff.left));
              }
  
              return result;
          },
  
          showSelection: function (drawn) {
              var cm = this.cm, display = cm.display;
              removeChildrenAndAdd(display.cursorDiv, drawn.cursors);
              removeChildrenAndAdd(display.selectionDiv, drawn.selection);
              if (drawn.teTop != null) {
                  this.wrapper.style.top = drawn.teTop + "px";
                  this.wrapper.style.left = drawn.teLeft + "px";
              }
          },
  
          // Reset the input to correspond to the selection (or to be empty,
          // when not typing and nothing is selected)
          reset: function (typing) {
              if (this.contextMenuPending) return;
              var minimal, selected, cm = this.cm, doc = cm.doc;
              if (cm.somethingSelected()) {
                  this.prevInput = "";
                  var range = doc.sel.primary();
                  minimal = hasCopyEvent &&
                      (range.to().line - range.from().line > 100 || (selected = cm.getSelection()).length > 1000);
                  var content = minimal ? "-" : selected || cm.getSelection();
                  this.textarea.value = content;
                  if (cm.state.focused) selectInput(this.textarea);
                  if (ie && ie_version >= 9) this.hasSelection = content;
              } else if (!typing) {
                  this.prevInput = this.textarea.value = "";
                  if (ie && ie_version >= 9) this.hasSelection = null;
              }
              this.inaccurateSelection = minimal;
          },
  
          getField: function () {
              return this.textarea;
          },
  
          supportsTouch: function () {
              return false;
          },
  
          focus: function () {
              if (this.cm.options.readOnly != "nocursor" && (!mobile || activeElt() != this.textarea)) {
                  try {
                      this.textarea.focus();
                  }
                  catch (e) {
                  } // IE8 will throw if the textarea is display: none or not in DOM
              }
          },
  
          blur: function () {
              this.textarea.blur();
          },
  
          resetPosition: function () {
              this.wrapper.style.top = this.wrapper.style.left = 0;
          },
  
          receivedFocus: function () {
              this.slowPoll();
          },
  
          // Poll for input changes, using the normal rate of polling. This
          // runs as long as the editor is focused.
          slowPoll: function () {
              var input = this;
              if (input.pollingFast) return;
              input.polling.set(this.cm.options.pollInterval, function () {
                  input.poll();
                  if (input.cm.state.focused) input.slowPoll();
              });
          },
  
          // When an event has just come in that is likely to add or change
          // something in the input textarea, we poll faster, to ensure that
          // the change appears on the screen quickly.
          fastPoll: function () {
              var missed = false, input = this;
              input.pollingFast = true;
              function p() {
                  var changed = input.poll();
                  if (!changed && !missed) {
                      missed = true;
                      input.polling.set(60, p);
                  }
                  else {
                      input.pollingFast = false;
                      input.slowPoll();
                  }
              }
  
              input.polling.set(20, p);
          },
  
          // Read input from the textarea, and update the document to match.
          // When something is selected, it is present in the textarea, and
          // selected (unless it is huge, in which case a placeholder is
          // used). When nothing is selected, the cursor sits after previously
          // seen text (can be empty), which is stored in prevInput (we must
          // not reset the textarea when typing, because that breaks IME).
          poll: function () {
              var cm = this.cm, input = this.textarea, prevInput = this.prevInput;
              // Since this is called a *lot*, try to bail out as cheaply as
              // possible when it is clear that nothing happened. hasSelection
              // will be the case when there is a lot of text in the textarea,
              // in which case reading its value would be expensive.
              if (!cm.state.focused || (hasSelection(input) && !prevInput) ||
                  isReadOnly(cm) || cm.options.disableInput || cm.state.keySeq)
                  return false;
              // See paste handler for more on the fakedLastChar kludge
              if (cm.state.pasteIncoming && cm.state.fakedLastChar) {
                  input.value = input.value.substring(0, input.value.length - 1);
                  cm.state.fakedLastChar = false;
              }
              var text = input.value;
              // If nothing changed, bail.
              if (text == prevInput && !cm.somethingSelected()) return false;
              // Work around nonsensical selection resetting in IE9/10, and
              // inexplicable appearance of private area unicode characters on
              // some key combos in Mac (#2689).
              if (ie && ie_version >= 9 && this.hasSelection === text ||
                  mac && /[\uf700-\uf7ff]/.test(text)) {
                  cm.display.input.reset();
                  return false;
              }
  
              if (text.charCodeAt(0) == 0x200b && cm.doc.sel == cm.display.selForContextMenu && !prevInput)
                  prevInput = "\u200b";
              // Find the part of the input that is actually new
              var same = 0, l = Math.min(prevInput.length, text.length);
              while (same < l && prevInput.charCodeAt(same) == text.charCodeAt(same)) ++same;
  
              var self = this;
              runInOp(cm, function () {
                  applyTextInput(cm, text.slice(same), prevInput.length - same);
  
                  // Don't leave long text in the textarea, since it makes further polling slow
                  if (text.length > 1000 || text.indexOf("\n") > -1) input.value = self.prevInput = "";
                  else self.prevInput = text;
              });
              return true;
          },
  
          ensurePolled: function () {
              if (this.pollingFast && this.poll()) this.pollingFast = false;
          },
  
          onKeyPress: function () {
              if (ie && ie_version >= 9) this.hasSelection = null;
              this.fastPoll();
          },
  
          onContextMenu: function (e) {
              var input = this, cm = input.cm, display = cm.display, te = input.textarea;
              var pos = posFromMouse(cm, e), scrollPos = display.scroller.scrollTop;
              if (!pos || presto) return; // Opera is difficult.
  
              // Reset the current text selection only if the click is done outside of the selection
              // and 'resetSelectionOnContextMenu' option is true.
              var reset = cm.options.resetSelectionOnContextMenu;
              if (reset && cm.doc.sel.contains(pos) == -1)
                  operation(cm, setSelection)(cm.doc, simpleSelection(pos), sel_dontScroll);
  
              var oldCSS = te.style.cssText;
              input.wrapper.style.position = "absolute";
              te.style.cssText = "position: fixed; width: 30px; height: 30px; top: " + (e.clientY - 5) +
                  "px; left: " + (e.clientX - 5) + "px; z-index: 1000; background: " +
                  (ie ? "rgba(255, 255, 255, .05)" : "transparent") +
                  "; outline: none; border-width: 0; outline: none; overflow: hidden; opacity: .05; filter: alpha(opacity=5);";
              if (webkit) var oldScrollY = window.scrollY; // Work around Chrome issue (#2712)
              display.input.focus();
              if (webkit) window.scrollTo(null, oldScrollY);
              display.input.reset();
              // Adds "Select all" to context menu in FF
              if (!cm.somethingSelected()) te.value = input.prevInput = " ";
              input.contextMenuPending = true;
              display.selForContextMenu = cm.doc.sel;
              clearTimeout(display.detectingSelectAll);
  
              // Select-all will be greyed out if there's nothing to select, so
              // this adds a zero-width space so that we can later check whether
              // it got selected.
              function prepareSelectAllHack() {
                  if (te.selectionStart != null) {
                      var selected = cm.somethingSelected();
                      var extval = te.value = "\u200b" + (selected ? te.value : "");
                      input.prevInput = selected ? "" : "\u200b";
                      te.selectionStart = 1;
                      te.selectionEnd = extval.length;
                      // Re-set this, in case some other handler touched the
                      // selection in the meantime.
                      display.selForContextMenu = cm.doc.sel;
                  }
              }
  
              function rehide() {
                  input.contextMenuPending = false;
                  input.wrapper.style.position = "relative";
                  te.style.cssText = oldCSS;
                  if (ie && ie_version < 9) display.scrollbars.setScrollTop(display.scroller.scrollTop = scrollPos);
  
                  // Try to detect the user choosing select-all
                  if (te.selectionStart != null) {
                      if (!ie || (ie && ie_version < 9)) prepareSelectAllHack();
                      var i = 0, poll = function () {
                          if (display.selForContextMenu == cm.doc.sel && te.selectionStart == 0)
                              operation(cm, commands.selectAll)(cm);
                          else if (i++ < 10) display.detectingSelectAll = setTimeout(poll, 500);
                          else display.input.reset();
                      };
                      display.detectingSelectAll = setTimeout(poll, 200);
                  }
              }
  
              if (ie && ie_version >= 9) prepareSelectAllHack();
              if (captureRightClick) {
                  e_stop(e);
                  var mouseup = function () {
                      off(window, "mouseup", mouseup);
                      setTimeout(rehide, 20);
                  };
                  on(window, "mouseup", mouseup);
              } else {
                  setTimeout(rehide, 50);
              }
          },
  
          setUneditable: nothing,
  
          needsContentAttribute: false
      }, TextareaInput.prototype);
  
      // CONTENTEDITABLE INPUT STYLE
  
      function ContentEditableInput(cm) {
          this.cm = cm;
          this.lastAnchorNode = this.lastAnchorOffset = this.lastFocusNode = this.lastFocusOffset = null;
          this.polling = new Delayed();
      }
  
      ContentEditableInput.prototype = copyObj({
          init: function (display) {
              var input = this, cm = input.cm;
              var div = input.div = display.lineDiv;
              div.contentEditable = "true";
              disableBrowserMagic(div);
  
              on(div, "paste", function (e) {
                  var pasted = e.clipboardData && e.clipboardData.getData("text/plain");
                  if (pasted) {
                      e.preventDefault();
                      cm.replaceSelection(pasted, null, "paste");
                  }
              });
  
              on(div, "compositionstart", function (e) {
                  var data = e.data;
                  input.composing = {sel: cm.doc.sel, data: data, startData: data};
                  if (!data) return;
                  var prim = cm.doc.sel.primary();
                  var line = cm.getLine(prim.head.line);
                  var found = line.indexOf(data, Math.max(0, prim.head.ch - data.length));
                  if (found > -1 && found <= prim.head.ch)
                      input.composing.sel = simpleSelection(Pos(prim.head.line, found),
                          Pos(prim.head.line, found + data.length));
              });
              on(div, "compositionupdate", function (e) {
                  input.composing.data = e.data;
              });
              on(div, "compositionend", function (e) {
                  var ours = input.composing;
                  if (!ours) return;
                  if (e.data != ours.startData && !/\u200b/.test(e.data))
                      ours.data = e.data;
                  // Need a small delay to prevent other code (input event,
                  // selection polling) from doing damage when fired right after
                  // compositionend.
                  setTimeout(function () {
                      if (!ours.handled)
                          input.applyComposition(ours);
                      if (input.composing == ours)
                          input.composing = null;
                  }, 50);
              });
  
              on(div, "touchstart", function () {
                  input.forceCompositionEnd();
              });
  
              on(div, "input", function () {
                  if (input.composing) return;
                  if (!input.pollContent())
                      runInOp(input.cm, function () {
                          regChange(cm);
                      });
              });
  
              function onCopyCut(e) {
                  if (cm.somethingSelected()) {
                      lastCopied = cm.getSelections();
                      if (e.type == "cut") cm.replaceSelection("", null, "cut");
                  } else {
                      var ranges = copyableRanges(cm);
                      lastCopied = ranges.text;
                      if (e.type == "cut") {
                          cm.operation(function () {
                              cm.setSelections(ranges.ranges, 0, sel_dontScroll);
                              cm.replaceSelection("", null, "cut");
                          });
                      }
                  }
                  // iOS exposes the clipboard API, but seems to discard content inserted into it
                  if (e.clipboardData && !ios) {
                      e.preventDefault();
                      e.clipboardData.clearData();
                      e.clipboardData.setData("text/plain", lastCopied.join("\n"));
                  } else {
                      // Old-fashioned briefly-focus-a-textarea hack
                      var kludge = hiddenTextarea(), te = kludge.firstChild;
                      cm.display.lineSpace.insertBefore(kludge, cm.display.lineSpace.firstChild);
                      te.value = lastCopied.join("\n");
                      var hadFocus = document.activeElement;
                      selectInput(te);
                      setTimeout(function () {
                          cm.display.lineSpace.removeChild(kludge);
                          hadFocus.focus();
                      }, 50);
                  }
              }
  
              on(div, "copy", onCopyCut);
              on(div, "cut", onCopyCut);
          },
  
          prepareSelection: function () {
              var result = prepareSelection(this.cm, false);
              result.focus = this.cm.state.focused;
              return result;
          },
  
          showSelection: function (info) {
              if (!info || !this.cm.display.view.length) return;
              if (info.focus) this.showPrimarySelection();
              this.showMultipleSelections(info);
          },
  
          showPrimarySelection: function () {
              var sel = window.getSelection(), prim = this.cm.doc.sel.primary();
              var curAnchor = domToPos(this.cm, sel.anchorNode, sel.anchorOffset);
              var curFocus = domToPos(this.cm, sel.focusNode, sel.focusOffset);
              if (curAnchor && !curAnchor.bad && curFocus && !curFocus.bad &&
                  cmp(minPos(curAnchor, curFocus), prim.from()) == 0 &&
                  cmp(maxPos(curAnchor, curFocus), prim.to()) == 0)
                  return;
  
              var start = posToDOM(this.cm, prim.from());
              var end = posToDOM(this.cm, prim.to());
              if (!start && !end) return;
  
              var view = this.cm.display.view;
              var old = sel.rangeCount && sel.getRangeAt(0);
              if (!start) {
                  start = {node: view[0].measure.map[2], offset: 0};
              } else if (!end) { // FIXME dangerously hacky
                  var measure = view[view.length - 1].measure;
                  var map = measure.maps ? measure.maps[measure.maps.length - 1] : measure.map;
                  end = {node: map[map.length - 1], offset: map[map.length - 2] - map[map.length - 3]};
              }
  
              try {
                  var rng = range(start.node, start.offset, end.offset, end.node);
              }
              catch (e) {
              } // Our model of the DOM might be outdated, in which case the range we try to set can be impossible
              if (rng) {
                  sel.removeAllRanges();
                  sel.addRange(rng);
                  if (old && sel.anchorNode == null) sel.addRange(old);
              }
              this.rememberSelection();
          },
  
          showMultipleSelections: function (info) {
              removeChildrenAndAdd(this.cm.display.cursorDiv, info.cursors);
              removeChildrenAndAdd(this.cm.display.selectionDiv, info.selection);
          },
  
          rememberSelection: function () {
              var sel = window.getSelection();
              this.lastAnchorNode = sel.anchorNode;
              this.lastAnchorOffset = sel.anchorOffset;
              this.lastFocusNode = sel.focusNode;
              this.lastFocusOffset = sel.focusOffset;
          },
  
          selectionInEditor: function () {
              var sel = window.getSelection();
              if (!sel.rangeCount) return false;
              var node = sel.getRangeAt(0).commonAncestorContainer;
              return contains(this.div, node);
          },
  
          focus: function () {
              if (this.cm.options.readOnly != "nocursor") this.div.focus();
          },
          blur: function () {
              this.div.blur();
          },
          getField: function () {
              return this.div;
          },
  
          supportsTouch: function () {
              return true;
          },
  
          receivedFocus: function () {
              var input = this;
              if (this.selectionInEditor())
                  this.pollSelection();
              else
                  runInOp(this.cm, function () {
                      input.cm.curOp.selectionChanged = true;
                  });
  
              function poll() {
                  if (input.cm.state.focused) {
                      input.pollSelection();
                      input.polling.set(input.cm.options.pollInterval, poll);
                  }
              }
  
              this.polling.set(this.cm.options.pollInterval, poll);
          },
  
          pollSelection: function () {
              if (this.composing) return;
  
              var sel = window.getSelection(), cm = this.cm;
              if (sel.anchorNode != this.lastAnchorNode || sel.anchorOffset != this.lastAnchorOffset ||
                  sel.focusNode != this.lastFocusNode || sel.focusOffset != this.lastFocusOffset) {
                  this.rememberSelection();
                  var anchor = domToPos(cm, sel.anchorNode, sel.anchorOffset);
                  var head = domToPos(cm, sel.focusNode, sel.focusOffset);
                  if (anchor && head) runInOp(cm, function () {
                      setSelection(cm.doc, simpleSelection(anchor, head), sel_dontScroll);
                      if (anchor.bad || head.bad) cm.curOp.selectionChanged = true;
                  });
              }
          },
  
          pollContent: function () {
              var cm = this.cm, display = cm.display, sel = cm.doc.sel.primary();
              var from = sel.from(), to = sel.to();
              if (from.line < display.viewFrom || to.line > display.viewTo - 1) return false;
  
              var fromIndex;
              if (from.line == display.viewFrom || (fromIndex = findViewIndex(cm, from.line)) == 0) {
                  var fromLine = lineNo(display.view[0].line);
                  var fromNode = display.view[0].node;
              } else {
                  var fromLine = lineNo(display.view[fromIndex].line);
                  var fromNode = display.view[fromIndex - 1].node.nextSibling;
              }
              var toIndex = findViewIndex(cm, to.line);
              if (toIndex == display.view.length - 1) {
                  var toLine = display.viewTo - 1;
                  var toNode = display.view[toIndex].node;
              } else {
                  var toLine = lineNo(display.view[toIndex + 1].line) - 1;
                  var toNode = display.view[toIndex + 1].node.previousSibling;
              }
  
              var newText = splitLines(domTextBetween(cm, fromNode, toNode, fromLine, toLine));
              var oldText = getBetween(cm.doc, Pos(fromLine, 0), Pos(toLine, getLine(cm.doc, toLine).text.length));
              while (newText.length > 1 && oldText.length > 1) {
                  if (lst(newText) == lst(oldText)) {
                      newText.pop();
                      oldText.pop();
                      toLine--;
                  }
                  else if (newText[0] == oldText[0]) {
                      newText.shift();
                      oldText.shift();
                      fromLine++;
                  }
                  else break;
              }
  
              var cutFront = 0, cutEnd = 0;
              var newTop = newText[0], oldTop = oldText[0], maxCutFront = Math.min(newTop.length, oldTop.length);
              while (cutFront < maxCutFront && newTop.charCodeAt(cutFront) == oldTop.charCodeAt(cutFront))
                  ++cutFront;
              var newBot = lst(newText), oldBot = lst(oldText);
              var maxCutEnd = Math.min(newBot.length - (newText.length == 1 ? cutFront : 0),
                  oldBot.length - (oldText.length == 1 ? cutFront : 0));
              while (cutEnd < maxCutEnd &&
              newBot.charCodeAt(newBot.length - cutEnd - 1) == oldBot.charCodeAt(oldBot.length - cutEnd - 1))
                  ++cutEnd;
  
              newText[newText.length - 1] = newBot.slice(0, newBot.length - cutEnd);
              newText[0] = newText[0].slice(cutFront);
  
              var chFrom = Pos(fromLine, cutFront);
              var chTo = Pos(toLine, oldText.length ? lst(oldText).length - cutEnd : 0);
              if (newText.length > 1 || newText[0] || cmp(chFrom, chTo)) {
                  replaceRange(cm.doc, newText, chFrom, chTo, "+input");
                  return true;
              }
          },
  
          ensurePolled: function () {
              this.forceCompositionEnd();
          },
          reset: function () {
              this.forceCompositionEnd();
          },
          forceCompositionEnd: function () {
              if (!this.composing || this.composing.handled) return;
              this.applyComposition(this.composing);
              this.composing.handled = true;
              this.div.blur();
              this.div.focus();
          },
          applyComposition: function (composing) {
              if (composing.data && composing.data != composing.startData)
                  operation(this.cm, applyTextInput)(this.cm, composing.data, 0, composing.sel);
          },
  
          setUneditable: function (node) {
              node.setAttribute("contenteditable", "false");
          },
  
          onKeyPress: function (e) {
              e.preventDefault();
              operation(this.cm, applyTextInput)(this.cm, String.fromCharCode(e.charCode == null ? e.keyCode : e.charCode), 0);
          },
  
          onContextMenu: nothing,
          resetPosition: nothing,
  
          needsContentAttribute: true
      }, ContentEditableInput.prototype);
  
      function posToDOM(cm, pos) {
          var view = findViewForLine(cm, pos.line);
          if (!view || view.hidden) return null;
          var line = getLine(cm.doc, pos.line);
          var info = mapFromLineView(view, line, pos.line);
  
          var order = getOrder(line), side = "left";
          if (order) {
              var partPos = getBidiPartAt(order, pos.ch);
              side = partPos % 2 ? "right" : "left";
          }
          var result = nodeAndOffsetInLineMap(info.map, pos.ch, "left");
          result.offset = result.collapse == "right" ? result.end : result.start;
          return result;
      }
  
      function badPos(pos, bad) {
          if (bad) pos.bad = true;
          return pos;
      }
  
      function domToPos(cm, node, offset) {
          var lineNode;
          if (node == cm.display.lineDiv) {
              lineNode = cm.display.lineDiv.childNodes[offset];
              if (!lineNode) return badPos(cm.clipPos(Pos(cm.display.viewTo - 1)), true);
              node = null;
              offset = 0;
          } else {
              for (lineNode = node; ; lineNode = lineNode.parentNode) {
                  if (!lineNode || lineNode == cm.display.lineDiv) return null;
                  if (lineNode.parentNode && lineNode.parentNode == cm.display.lineDiv) break;
              }
          }
          for (var i = 0; i < cm.display.view.length; i++) {
              var lineView = cm.display.view[i];
              if (lineView.node == lineNode)
                  return locateNodeInLineView(lineView, node, offset);
          }
      }
  
      function locateNodeInLineView(lineView, node, offset) {
          var wrapper = lineView.text.firstChild, bad = false;
          if (!node || !contains(wrapper, node)) return badPos(Pos(lineNo(lineView.line), 0), true);
          if (node == wrapper) {
              bad = true;
              node = wrapper.childNodes[offset];
              offset = 0;
              if (!node) {
                  var line = lineView.rest ? lst(lineView.rest) : lineView.line;
                  return badPos(Pos(lineNo(line), line.text.length), bad);
              }
          }
  
          var textNode = node.nodeType == 3 ? node : null, topNode = node;
          if (!textNode && node.childNodes.length == 1 && node.firstChild.nodeType == 3) {
              textNode = node.firstChild;
              if (offset) offset = textNode.nodeValue.length;
          }
          while (topNode.parentNode != wrapper) topNode = topNode.parentNode;
          var measure = lineView.measure, maps = measure.maps;
  
          function find(textNode, topNode, offset) {
              for (var i = -1; i < (maps ? maps.length : 0); i++) {
                  var map = i < 0 ? measure.map : maps[i];
                  for (var j = 0; j < map.length; j += 3) {
                      var curNode = map[j + 2];
                      if (curNode == textNode || curNode == topNode) {
                          var line = lineNo(i < 0 ? lineView.line : lineView.rest[i]);
                          var ch = map[j] + offset;
                          if (offset < 0 || curNode != textNode) ch = map[j + (offset ? 1 : 0)];
                          return Pos(line, ch);
                      }
                  }
              }
          }
  
          var found = find(textNode, topNode, offset);
          if (found) return badPos(found, bad);
  
          // FIXME this is all really shaky. might handle the few cases it needs to handle, but likely to cause problems
          for (var after = topNode.nextSibling, dist = textNode ? textNode.nodeValue.length - offset : 0; after; after = after.nextSibling) {
              found = find(after, after.firstChild, 0);
              if (found)
                  return badPos(Pos(found.line, found.ch - dist), bad);
              else
                  dist += after.textContent.length;
          }
          for (var before = topNode.previousSibling, dist = offset; before; before = before.previousSibling) {
              found = find(before, before.firstChild, -1);
              if (found)
                  return badPos(Pos(found.line, found.ch + dist), bad);
              else
                  dist += after.textContent.length;
          }
      }
  
      function domTextBetween(cm, from, to, fromLine, toLine) {
          var text = "", closing = false;
  
          function recognizeMarker(id) {
              return function (marker) {
                  return marker.id == id;
              };
          }
  
          function walk(node) {
              if (node.nodeType == 1) {
                  var cmText = node.getAttribute("cm-text");
                  if (cmText != null) {
                      if (cmText == "") cmText = node.textContent.replace(/\u200b/g, "");
                      text += cmText;
                      return;
                  }
                  var markerID = node.getAttribute("cm-marker"), range;
                  if (markerID) {
                      var found = cm.findMarks(Pos(fromLine, 0), Pos(toLine + 1, 0), recognizeMarker(+markerID));
                      if (found.length && (range = found[0].find()))
                          text += getBetween(cm.doc, range.from, range.to).join("\n");
                      return;
                  }
                  if (node.getAttribute("contenteditable") == "false") return;
                  for (var i = 0; i < node.childNodes.length; i++)
                      walk(node.childNodes[i]);
                  if (/^(pre|div|p)$/i.test(node.nodeName))
                      closing = true;
              } else if (node.nodeType == 3) {
                  var val = node.nodeValue;
                  if (!val) return;
                  if (closing) {
                      text += "\n";
                      closing = false;
                  }
                  text += val;
              }
          }
  
          for (; ;) {
              walk(from);
              if (from == to) break;
              from = from.nextSibling;
          }
          return text;
      }
  
      CodeMirror.inputStyles = {"textarea": TextareaInput, "contenteditable": ContentEditableInput};
  
      // SELECTION / CURSOR
  
      // Selection objects are immutable. A new one is created every time
      // the selection changes. A selection is one or more non-overlapping
      // (and non-touching) ranges, sorted, and an integer that indicates
      // which one is the primary selection (the one that's scrolled into
      // view, that getCursor returns, etc).
      function Selection(ranges, primIndex) {
          this.ranges = ranges;
          this.primIndex = primIndex;
      }
  
      Selection.prototype = {
          primary: function () {
              return this.ranges[this.primIndex];
          },
          equals: function (other) {
              if (other == this) return true;
              if (other.primIndex != this.primIndex || other.ranges.length != this.ranges.length) return false;
              for (var i = 0; i < this.ranges.length; i++) {
                  var here = this.ranges[i], there = other.ranges[i];
                  if (cmp(here.anchor, there.anchor) != 0 || cmp(here.head, there.head) != 0) return false;
              }
              return true;
          },
          deepCopy: function () {
              for (var out = [], i = 0; i < this.ranges.length; i++)
                  out[i] = new Range(copyPos(this.ranges[i].anchor), copyPos(this.ranges[i].head));
              return new Selection(out, this.primIndex);
          },
          somethingSelected: function () {
              for (var i = 0; i < this.ranges.length; i++)
                  if (!this.ranges[i].empty()) return true;
              return false;
          },
          contains: function (pos, end) {
              if (!end) end = pos;
              for (var i = 0; i < this.ranges.length; i++) {
                  var range = this.ranges[i];
                  if (cmp(end, range.from()) >= 0 && cmp(pos, range.to()) <= 0)
                      return i;
              }
              return -1;
          }
      };
  
      function Range(anchor, head) {
          this.anchor = anchor;
          this.head = head;
      }
  
      Range.prototype = {
          from: function () {
              return minPos(this.anchor, this.head);
          },
          to: function () {
              return maxPos(this.anchor, this.head);
          },
          empty: function () {
              return this.head.line == this.anchor.line && this.head.ch == this.anchor.ch;
          }
      };
  
      // Take an unsorted, potentially overlapping set of ranges, and
      // build a selection out of it. 'Consumes' ranges array (modifying
      // it).
      function normalizeSelection(ranges, primIndex) {
          var prim = ranges[primIndex];
          ranges.sort(function (a, b) {
              return cmp(a.from(), b.from());
          });
          primIndex = indexOf(ranges, prim);
          for (var i = 1; i < ranges.length; i++) {
              var cur = ranges[i], prev = ranges[i - 1];
              if (cmp(prev.to(), cur.from()) >= 0) {
                  var from = minPos(prev.from(), cur.from()), to = maxPos(prev.to(), cur.to());
                  var inv = prev.empty() ? cur.from() == cur.head : prev.from() == prev.head;
                  if (i <= primIndex) --primIndex;
                  ranges.splice(--i, 2, new Range(inv ? to : from, inv ? from : to));
              }
          }
          return new Selection(ranges, primIndex);
      }
  
      function simpleSelection(anchor, head) {
          return new Selection([new Range(anchor, head || anchor)], 0);
      }
  
      // Most of the external API clips given positions to make sure they
      // actually exist within the document.
      function clipLine(doc, n) {
          return Math.max(doc.first, Math.min(n, doc.first + doc.size - 1));
      }
  
      function clipPos(doc, pos) {
          if (pos.line < doc.first) return Pos(doc.first, 0);
          var last = doc.first + doc.size - 1;
          if (pos.line > last) return Pos(last, getLine(doc, last).text.length);
          return clipToLen(pos, getLine(doc, pos.line).text.length);
      }
  
      function clipToLen(pos, linelen) {
          var ch = pos.ch;
          if (ch == null || ch > linelen) return Pos(pos.line, linelen);
          else if (ch < 0) return Pos(pos.line, 0);
          else return pos;
      }
  
      function isLine(doc, l) {
          return l >= doc.first && l < doc.first + doc.size;
      }
  
      function clipPosArray(doc, array) {
          for (var out = [], i = 0; i < array.length; i++) out[i] = clipPos(doc, array[i]);
          return out;
      }
  
      // SELECTION UPDATES
  
      // The 'scroll' parameter given to many of these indicated whether
      // the new cursor position should be scrolled into view after
      // modifying the selection.
  
      // If shift is held or the extend flag is set, extends a range to
      // include a given position (and optionally a second position).
      // Otherwise, simply returns the range between the given positions.
      // Used for cursor motion and such.
      function extendRange(doc, range, head, other) {
          if (doc.cm && doc.cm.display.shift || doc.extend) {
              var anchor = range.anchor;
              if (other) {
                  var posBefore = cmp(head, anchor) < 0;
                  if (posBefore != (cmp(other, anchor) < 0)) {
                      anchor = head;
                      head = other;
                  } else if (posBefore != (cmp(head, other) < 0)) {
                      head = other;
                  }
              }
              return new Range(anchor, head);
          } else {
              return new Range(other || head, head);
          }
      }
  
      // Extend the primary selection range, discard the rest.
      function extendSelection(doc, head, other, options) {
          setSelection(doc, new Selection([extendRange(doc, doc.sel.primary(), head, other)], 0), options);
      }
  
      // Extend all selections (pos is an array of selections with length
      // equal the number of selections)
      function extendSelections(doc, heads, options) {
          for (var out = [], i = 0; i < doc.sel.ranges.length; i++)
              out[i] = extendRange(doc, doc.sel.ranges[i], heads[i], null);
          var newSel = normalizeSelection(out, doc.sel.primIndex);
          setSelection(doc, newSel, options);
      }
  
      // Updates a single range in the selection.
      function replaceOneSelection(doc, i, range, options) {
          var ranges = doc.sel.ranges.slice(0);
          ranges[i] = range;
          setSelection(doc, normalizeSelection(ranges, doc.sel.primIndex), options);
      }
  
      // Reset the selection to a single range.
      function setSimpleSelection(doc, anchor, head, options) {
          setSelection(doc, simpleSelection(anchor, head), options);
      }
  
      // Give beforeSelectionChange handlers a change to influence a
      // selection update.
      function filterSelectionChange(doc, sel) {
          var obj = {
              ranges: sel.ranges,
              update: function (ranges) {
                  this.ranges = [];
                  for (var i = 0; i < ranges.length; i++)
                      this.ranges[i] = new Range(clipPos(doc, ranges[i].anchor),
                          clipPos(doc, ranges[i].head));
              }
          };
          signal(doc, "beforeSelectionChange", doc, obj);
          if (doc.cm) signal(doc.cm, "beforeSelectionChange", doc.cm, obj);
          if (obj.ranges != sel.ranges) return normalizeSelection(obj.ranges, obj.ranges.length - 1);
          else return sel;
      }
  
      function setSelectionReplaceHistory(doc, sel, options) {
          var done = doc.history.done, last = lst(done);
          if (last && last.ranges) {
              done[done.length - 1] = sel;
              setSelectionNoUndo(doc, sel, options);
          } else {
              setSelection(doc, sel, options);
          }
      }
  
      // Set a new selection.
      function setSelection(doc, sel, options) {
          setSelectionNoUndo(doc, sel, options);
          addSelectionToHistory(doc, doc.sel, doc.cm ? doc.cm.curOp.id : NaN, options);
      }
  
      function setSelectionNoUndo(doc, sel, options) {
          if (hasHandler(doc, "beforeSelectionChange") || doc.cm && hasHandler(doc.cm, "beforeSelectionChange"))
              sel = filterSelectionChange(doc, sel);
  
          var bias = options && options.bias ||
              (cmp(sel.primary().head, doc.sel.primary().head) < 0 ? -1 : 1);
          setSelectionInner(doc, skipAtomicInSelection(doc, sel, bias, true));
  
          if (!(options && options.scroll === false) && doc.cm)
              ensureCursorVisible(doc.cm);
      }
  
      function setSelectionInner(doc, sel) {
          if (sel.equals(doc.sel)) return;
  
          doc.sel = sel;
  
          if (doc.cm) {
              doc.cm.curOp.updateInput = doc.cm.curOp.selectionChanged = true;
              signalCursorActivity(doc.cm);
          }
          signalLater(doc, "cursorActivity", doc);
      }
  
      // Verify that the selection does not partially select any atomic
      // marked ranges.
      function reCheckSelection(doc) {
          setSelectionInner(doc, skipAtomicInSelection(doc, doc.sel, null, false), sel_dontScroll);
      }
  
      // Return a selection that does not partially select any atomic
      // ranges.
      function skipAtomicInSelection(doc, sel, bias, mayClear) {
          var out;
          for (var i = 0; i < sel.ranges.length; i++) {
              var range = sel.ranges[i];
              var newAnchor = skipAtomic(doc, range.anchor, bias, mayClear);
              var newHead = skipAtomic(doc, range.head, bias, mayClear);
              if (out || newAnchor != range.anchor || newHead != range.head) {
                  if (!out) out = sel.ranges.slice(0, i);
                  out[i] = new Range(newAnchor, newHead);
              }
          }
          return out ? normalizeSelection(out, sel.primIndex) : sel;
      }
  
      // Ensure a given position is not inside an atomic range.
      function skipAtomic(doc, pos, bias, mayClear) {
          var flipped = false, curPos = pos;
          var dir = bias || 1;
          doc.cantEdit = false;
          search: for (; ;) {
              var line = getLine(doc, curPos.line);
              if (line.markedSpans) {
                  for (var i = 0; i < line.markedSpans.length; ++i) {
                      var sp = line.markedSpans[i], m = sp.marker;
                      if ((sp.from == null || (m.inclusiveLeft ? sp.from <= curPos.ch : sp.from < curPos.ch)) &&
                          (sp.to == null || (m.inclusiveRight ? sp.to >= curPos.ch : sp.to > curPos.ch))) {
                          if (mayClear) {
                              signal(m, "beforeCursorEnter");
                              if (m.explicitlyCleared) {
                                  if (!line.markedSpans) break;
                                  else {
                                      --i;
                                      continue;
                                  }
                              }
                          }
                          if (!m.atomic) continue;
                          var newPos = m.find(dir < 0 ? -1 : 1);
                          if (cmp(newPos, curPos) == 0) {
                              newPos.ch += dir;
                              if (newPos.ch < 0) {
                                  if (newPos.line > doc.first) newPos = clipPos(doc, Pos(newPos.line - 1));
                                  else newPos = null;
                              } else if (newPos.ch > line.text.length) {
                                  if (newPos.line < doc.first + doc.size - 1) newPos = Pos(newPos.line + 1, 0);
                                  else newPos = null;
                              }
                              if (!newPos) {
                                  if (flipped) {
                                      // Driven in a corner -- no valid cursor position found at all
                                      // -- try again *with* clearing, if we didn't already
                                      if (!mayClear) return skipAtomic(doc, pos, bias, true);
                                      // Otherwise, turn off editing until further notice, and return the start of the doc
                                      doc.cantEdit = true;
                                      return Pos(doc.first, 0);
                                  }
                                  flipped = true;
                                  newPos = pos;
                                  dir = -dir;
                              }
                          }
                          curPos = newPos;
                          continue search;
                      }
                  }
              }
              return curPos;
          }
      }
  
      // SELECTION DRAWING
  
      function updateSelection(cm) {
          cm.display.input.showSelection(cm.display.input.prepareSelection());
      }
  
      function prepareSelection(cm, primary) {
          var doc = cm.doc, result = {};
          var curFragment = result.cursors = document.createDocumentFragment();
          var selFragment = result.selection = document.createDocumentFragment();
  
          for (var i = 0; i < doc.sel.ranges.length; i++) {
              if (primary === false && i == doc.sel.primIndex) continue;
              var range = doc.sel.ranges[i];
              var collapsed = range.empty();
              if (collapsed || cm.options.showCursorWhenSelecting)
                  drawSelectionCursor(cm, range, curFragment);
              if (!collapsed)
                  drawSelectionRange(cm, range, selFragment);
          }
          return result;
      }
  
      // Draws a cursor for the given range
      function drawSelectionCursor(cm, range, output) {
          var pos = cursorCoords(cm, range.head, "div", null, null, !cm.options.singleCursorHeightPerLine);
  
          var cursor = output.appendChild(elt("div", "\u00a0", "CodeMirror-cursor"));
          cursor.style.left = pos.left + "px";
          cursor.style.top = pos.top + "px";
          cursor.style.height = Math.max(0, pos.bottom - pos.top) * cm.options.cursorHeight + "px";
  
          if (pos.other) {
              // Secondary cursor, shown when on a 'jump' in bi-directional text
              var otherCursor = output.appendChild(elt("div", "\u00a0", "CodeMirror-cursor CodeMirror-secondarycursor"));
              otherCursor.style.display = "";
              otherCursor.style.left = pos.other.left + "px";
              otherCursor.style.top = pos.other.top + "px";
              otherCursor.style.height = (pos.other.bottom - pos.other.top) * .85 + "px";
          }
      }
  
      // Draws the given range as a highlighted selection
      function drawSelectionRange(cm, range, output) {
          var display = cm.display, doc = cm.doc;
          var fragment = document.createDocumentFragment();
          var padding = paddingH(cm.display), leftSide = padding.left;
          var rightSide = Math.max(display.sizerWidth, displayWidth(cm) - display.sizer.offsetLeft) - padding.right;
  
          function add(left, top, width, bottom) {
              if (top < 0) top = 0;
              top = Math.round(top);
              bottom = Math.round(bottom);
              fragment.appendChild(elt("div", null, "CodeMirror-selected", "position: absolute; left: " + left +
                  "px; top: " + top + "px; width: " + (width == null ? rightSide - left : width) +
                  "px; height: " + (bottom - top) + "px"));
          }
  
          function drawForLine(line, fromArg, toArg) {
              var lineObj = getLine(doc, line);
              var lineLen = lineObj.text.length;
              var start, end;
  
              function coords(ch, bias) {
                  return charCoords(cm, Pos(line, ch), "div", lineObj, bias);
              }
  
              iterateBidiSections(getOrder(lineObj), fromArg || 0, toArg == null ? lineLen : toArg, function (from, to, dir) {
                  var leftPos = coords(from, "left"), rightPos, left, right;
                  if (from == to) {
                      rightPos = leftPos;
                      left = right = leftPos.left;
                  } else {
                      rightPos = coords(to - 1, "right");
                      if (dir == "rtl") {
                          var tmp = leftPos;
                          leftPos = rightPos;
                          rightPos = tmp;
                      }
                      left = leftPos.left;
                      right = rightPos.right;
                  }
                  if (fromArg == null && from == 0) left = leftSide;
                  if (rightPos.top - leftPos.top > 3) { // Different lines, draw top part
                      add(left, leftPos.top, null, leftPos.bottom);
                      left = leftSide;
                      if (leftPos.bottom < rightPos.top) add(left, leftPos.bottom, null, rightPos.top);
                  }
                  if (toArg == null && to == lineLen) right = rightSide;
                  if (!start || leftPos.top < start.top || leftPos.top == start.top && leftPos.left < start.left)
                      start = leftPos;
                  if (!end || rightPos.bottom > end.bottom || rightPos.bottom == end.bottom && rightPos.right > end.right)
                      end = rightPos;
                  if (left < leftSide + 1) left = leftSide;
                  add(left, rightPos.top, right - left, rightPos.bottom);
              });
              return {start: start, end: end};
          }
  
          var sFrom = range.from(), sTo = range.to();
          if (sFrom.line == sTo.line) {
              drawForLine(sFrom.line, sFrom.ch, sTo.ch);
          } else {
              var fromLine = getLine(doc, sFrom.line), toLine = getLine(doc, sTo.line);
              var singleVLine = visualLine(fromLine) == visualLine(toLine);
              var leftEnd = drawForLine(sFrom.line, sFrom.ch, singleVLine ? fromLine.text.length + 1 : null).end;
              var rightStart = drawForLine(sTo.line, singleVLine ? 0 : null, sTo.ch).start;
              if (singleVLine) {
                  if (leftEnd.top < rightStart.top - 2) {
                      add(leftEnd.right, leftEnd.top, null, leftEnd.bottom);
                      add(leftSide, rightStart.top, rightStart.left, rightStart.bottom);
                  } else {
                      add(leftEnd.right, leftEnd.top, rightStart.left - leftEnd.right, leftEnd.bottom);
                  }
              }
              if (leftEnd.bottom < rightStart.top)
                  add(leftSide, leftEnd.bottom, null, rightStart.top);
          }
  
          output.appendChild(fragment);
      }
  
      // Cursor-blinking
      function restartBlink(cm) {
          if (!cm.state.focused) return;
          var display = cm.display;
          clearInterval(display.blinker);
          var on = true;
          display.cursorDiv.style.visibility = "";
          if (cm.options.cursorBlinkRate > 0)
              display.blinker = setInterval(function () {
                  display.cursorDiv.style.visibility = (on = !on) ? "" : "hidden";
              }, cm.options.cursorBlinkRate);
          else if (cm.options.cursorBlinkRate < 0)
              display.cursorDiv.style.visibility = "hidden";
      }
  
      // HIGHLIGHT WORKER
  
      function startWorker(cm, time) {
          if (cm.doc.mode.startState && cm.doc.frontier < cm.display.viewTo)
              cm.state.highlight.set(time, bind(highlightWorker, cm));
      }
  
      function highlightWorker(cm) {
          var doc = cm.doc;
          if (doc.frontier < doc.first) doc.frontier = doc.first;
          if (doc.frontier >= cm.display.viewTo) return;
          var end = +new Date + cm.options.workTime;
          var state = copyState(doc.mode, getStateBefore(cm, doc.frontier));
          var changedLines = [];
  
          doc.iter(doc.frontier, Math.min(doc.first + doc.size, cm.display.viewTo + 500), function (line) {
              if (doc.frontier >= cm.display.viewFrom) { // Visible
                  var oldStyles = line.styles;
                  var highlighted = highlightLine(cm, line, state, true);
                  line.styles = highlighted.styles;
                  var oldCls = line.styleClasses, newCls = highlighted.classes;
                  if (newCls) line.styleClasses = newCls;
                  else if (oldCls) line.styleClasses = null;
                  var ischange = !oldStyles || oldStyles.length != line.styles.length ||
                      oldCls != newCls && (!oldCls || !newCls || oldCls.bgClass != newCls.bgClass || oldCls.textClass != newCls.textClass);
                  for (var i = 0; !ischange && i < oldStyles.length; ++i) ischange = oldStyles[i] != line.styles[i];
                  if (ischange) changedLines.push(doc.frontier);
                  line.stateAfter = copyState(doc.mode, state);
              } else {
                  processLine(cm, line.text, state);
                  line.stateAfter = doc.frontier % 5 == 0 ? copyState(doc.mode, state) : null;
              }
              ++doc.frontier;
              if (+new Date > end) {
                  startWorker(cm, cm.options.workDelay);
                  return true;
              }
          });
          if (changedLines.length) runInOp(cm, function () {
              for (var i = 0; i < changedLines.length; i++)
                  regLineChange(cm, changedLines[i], "text");
          });
      }
  
      // Finds the line to start with when starting a parse. Tries to
      // find a line with a stateAfter, so that it can start with a
      // valid state. If that fails, it returns the line with the
      // smallest indentation, which tends to need the least context to
      // parse correctly.
      function findStartLine(cm, n, precise) {
          var minindent, minline, doc = cm.doc;
          var lim = precise ? -1 : n - (cm.doc.mode.innerMode ? 1000 : 100);
          for (var search = n; search > lim; --search) {
              if (search <= doc.first) return doc.first;
              var line = getLine(doc, search - 1);
              if (line.stateAfter && (!precise || search <= doc.frontier)) return search;
              var indented = countColumn(line.text, null, cm.options.tabSize);
              if (minline == null || minindent > indented) {
                  minline = search - 1;
                  minindent = indented;
              }
          }
          return minline;
      }
  
      function getStateBefore(cm, n, precise) {
          var doc = cm.doc, display = cm.display;
          if (!doc.mode.startState) return true;
          var pos = findStartLine(cm, n, precise), state = pos > doc.first && getLine(doc, pos - 1).stateAfter;
          if (!state) state = startState(doc.mode);
          else state = copyState(doc.mode, state);
          doc.iter(pos, n, function (line) {
              processLine(cm, line.text, state);
              var save = pos == n - 1 || pos % 5 == 0 || pos >= display.viewFrom && pos < display.viewTo;
              line.stateAfter = save ? copyState(doc.mode, state) : null;
              ++pos;
          });
          if (precise) doc.frontier = pos;
          return state;
      }
  
      // POSITION MEASUREMENT
  
      function paddingTop(display) {
          return display.lineSpace.offsetTop;
      }
  
      function paddingVert(display) {
          return display.mover.offsetHeight - display.lineSpace.offsetHeight;
      }
  
      function paddingH(display) {
          if (display.cachedPaddingH) return display.cachedPaddingH;
          var e = removeChildrenAndAdd(display.measure, elt("pre", "x"));
          var style = window.getComputedStyle ? window.getComputedStyle(e) : e.currentStyle;
          var data = {left: parseInt(style.paddingLeft), right: parseInt(style.paddingRight)};
          if (!isNaN(data.left) && !isNaN(data.right)) display.cachedPaddingH = data;
          return data;
      }
  
      function scrollGap(cm) {
          return scrollerGap - cm.display.nativeBarWidth;
      }
  
      function displayWidth(cm) {
          return cm.display.scroller.clientWidth - scrollGap(cm) - cm.display.barWidth;
      }
  
      function displayHeight(cm) {
          return cm.display.scroller.clientHeight - scrollGap(cm) - cm.display.barHeight;
      }
  
      // Ensure the lineView.wrapping.heights array is populated. This is
      // an array of bottom offsets for the lines that make up a drawn
      // line. When lineWrapping is on, there might be more than one
      // height.
      function ensureLineHeights(cm, lineView, rect) {
          var wrapping = cm.options.lineWrapping;
          var curWidth = wrapping && displayWidth(cm);
          if (!lineView.measure.heights || wrapping && lineView.measure.width != curWidth) {
              var heights = lineView.measure.heights = [];
              if (wrapping) {
                  lineView.measure.width = curWidth;
                  var rects = lineView.text.firstChild.getClientRects();
                  for (var i = 0; i < rects.length - 1; i++) {
                      var cur = rects[i], next = rects[i + 1];
                      if (Math.abs(cur.bottom - next.bottom) > 2)
                          heights.push((cur.bottom + next.top) / 2 - rect.top);
                  }
              }
              heights.push(rect.bottom - rect.top);
          }
      }
  
      // Find a line map (mapping character offsets to text nodes) and a
      // measurement cache for the given line number. (A line view might
      // contain multiple lines when collapsed ranges are present.)
      function mapFromLineView(lineView, line, lineN) {
          if (lineView.line == line)
              return {map: lineView.measure.map, cache: lineView.measure.cache};
          for (var i = 0; i < lineView.rest.length; i++)
              if (lineView.rest[i] == line)
                  return {map: lineView.measure.maps[i], cache: lineView.measure.caches[i]};
          for (var i = 0; i < lineView.rest.length; i++)
              if (lineNo(lineView.rest[i]) > lineN)
                  return {map: lineView.measure.maps[i], cache: lineView.measure.caches[i], before: true};
      }
  
      // Render a line into the hidden node display.externalMeasured. Used
      // when measurement is needed for a line that's not in the viewport.
      function updateExternalMeasurement(cm, line) {
          line = visualLine(line);
          var lineN = lineNo(line);
          var view = cm.display.externalMeasured = new LineView(cm.doc, line, lineN);
          view.lineN = lineN;
          var built = view.built = buildLineContent(cm, view);
          view.text = built.pre;
          removeChildrenAndAdd(cm.display.lineMeasure, built.pre);
          return view;
      }
  
      // Get a {top, bottom, left, right} box (in line-local coordinates)
      // for a given character.
      function measureChar(cm, line, ch, bias) {
          return measureCharPrepared(cm, prepareMeasureForLine(cm, line), ch, bias);
      }
  
      // Find a line view that corresponds to the given line number.
      function findViewForLine(cm, lineN) {
          if (lineN >= cm.display.viewFrom && lineN < cm.display.viewTo)
              return cm.display.view[findViewIndex(cm, lineN)];
          var ext = cm.display.externalMeasured;
          if (ext && lineN >= ext.lineN && lineN < ext.lineN + ext.size)
              return ext;
      }
  
      // Measurement can be split in two steps, the set-up work that
      // applies to the whole line, and the measurement of the actual
      // character. Functions like coordsChar, that need to do a lot of
      // measurements in a row, can thus ensure that the set-up work is
      // only done once.
      function prepareMeasureForLine(cm, line) {
          var lineN = lineNo(line);
          var view = findViewForLine(cm, lineN);
          if (view && !view.text)
              view = null;
          else if (view && view.changes)
              updateLineForChanges(cm, view, lineN, getDimensions(cm));
          if (!view)
              view = updateExternalMeasurement(cm, line);
  
          var info = mapFromLineView(view, line, lineN);
          return {
              line: line, view: view, rect: null,
              map: info.map, cache: info.cache, before: info.before,
              hasHeights: false
          };
      }
  
      // Given a prepared measurement object, measures the position of an
      // actual character (or fetches it from the cache).
      function measureCharPrepared(cm, prepared, ch, bias, varHeight) {
          if (prepared.before) ch = -1;
          var key = ch + (bias || ""), found;
          if (prepared.cache.hasOwnProperty(key)) {
              found = prepared.cache[key];
          } else {
              if (!prepared.rect)
                  prepared.rect = prepared.view.text.getBoundingClientRect();
              if (!prepared.hasHeights) {
                  ensureLineHeights(cm, prepared.view, prepared.rect);
                  prepared.hasHeights = true;
              }
              found = measureCharInner(cm, prepared, ch, bias);
              if (!found.bogus) prepared.cache[key] = found;
          }
          return {
              left: found.left, right: found.right,
              top: varHeight ? found.rtop : found.top,
              bottom: varHeight ? found.rbottom : found.bottom
          };
      }
  
      var nullRect = {left: 0, right: 0, top: 0, bottom: 0};
  
      function nodeAndOffsetInLineMap(map, ch, bias) {
          var node, start, end, collapse;
          // First, search the line map for the text node corresponding to,
          // or closest to, the target character.
          for (var i = 0; i < map.length; i += 3) {
              var mStart = map[i], mEnd = map[i + 1];
              if (ch < mStart) {
                  start = 0;
                  end = 1;
                  collapse = "left";
              } else if (ch < mEnd) {
                  start = ch - mStart;
                  end = start + 1;
              } else if (i == map.length - 3 || ch == mEnd && map[i + 3] > ch) {
                  end = mEnd - mStart;
                  start = end - 1;
                  if (ch >= mEnd) collapse = "right";
              }
              if (start != null) {
                  node = map[i + 2];
                  if (mStart == mEnd && bias == (node.insertLeft ? "left" : "right"))
                      collapse = bias;
                  if (bias == "left" && start == 0)
                      while (i && map[i - 2] == map[i - 3] && map[i - 1].insertLeft) {
                          node = map[(i -= 3) + 2];
                          collapse = "left";
                      }
                  if (bias == "right" && start == mEnd - mStart)
                      while (i < map.length - 3 && map[i + 3] == map[i + 4] && !map[i + 5].insertLeft) {
                          node = map[(i += 3) + 2];
                          collapse = "right";
                      }
                  break;
              }
          }
          return {node: node, start: start, end: end, collapse: collapse, coverStart: mStart, coverEnd: mEnd};
      }
  
      function measureCharInner(cm, prepared, ch, bias) {
          var place = nodeAndOffsetInLineMap(prepared.map, ch, bias);
          var node = place.node, start = place.start, end = place.end, collapse = place.collapse;
  
          var rect;
          if (node.nodeType == 3) { // If it is a text node, use a range to retrieve the coordinates.
              for (var i = 0; i < 4; i++) { // Retry a maximum of 4 times when nonsense rectangles are returned
                  while (start && isExtendingChar(prepared.line.text.charAt(place.coverStart + start))) --start;
                  while (place.coverStart + end < place.coverEnd && isExtendingChar(prepared.line.text.charAt(place.coverStart + end))) ++end;
                  if (ie && ie_version < 9 && start == 0 && end == place.coverEnd - place.coverStart) {
                      rect = node.parentNode.getBoundingClientRect();
                  } else if (ie && cm.options.lineWrapping) {
                      var rects = range(node, start, end).getClientRects();
                      if (rects.length)
                          rect = rects[bias == "right" ? rects.length - 1 : 0];
                      else
                          rect = nullRect;
                  } else {
                      rect = range(node, start, end).getBoundingClientRect() || nullRect;
                  }
                  if (rect.left || rect.right || start == 0) break;
                  end = start;
                  start = start - 1;
                  collapse = "right";
              }
              if (ie && ie_version < 11) rect = maybeUpdateRectForZooming(cm.display.measure, rect);
          } else { // If it is a widget, simply get the box for the whole widget.
              if (start > 0) collapse = bias = "right";
              var rects;
              if (cm.options.lineWrapping && (rects = node.getClientRects()).length > 1)
                  rect = rects[bias == "right" ? rects.length - 1 : 0];
              else
                  rect = node.getBoundingClientRect();
          }
          if (ie && ie_version < 9 && !start && (!rect || !rect.left && !rect.right)) {
              var rSpan = node.parentNode.getClientRects()[0];
              if (rSpan)
                  rect = {
                      left: rSpan.left,
                      right: rSpan.left + charWidth(cm.display),
                      top: rSpan.top,
                      bottom: rSpan.bottom
                  };
              else
                  rect = nullRect;
          }
  
          var rtop = rect.top - prepared.rect.top, rbot = rect.bottom - prepared.rect.top;
          var mid = (rtop + rbot) / 2;
          var heights = prepared.view.measure.heights;
          for (var i = 0; i < heights.length - 1; i++)
              if (mid < heights[i]) break;
          var top = i ? heights[i - 1] : 0, bot = heights[i];
          var result = {
              left: (collapse == "right" ? rect.right : rect.left) - prepared.rect.left,
              right: (collapse == "left" ? rect.left : rect.right) - prepared.rect.left,
              top: top, bottom: bot
          };
          if (!rect.left && !rect.right) result.bogus = true;
          if (!cm.options.singleCursorHeightPerLine) {
              result.rtop = rtop;
              result.rbottom = rbot;
          }
  
          return result;
      }
  
      // Work around problem with bounding client rects on ranges being
      // returned incorrectly when zoomed on IE10 and below.
      function maybeUpdateRectForZooming(measure, rect) {
          if (!window.screen || screen.logicalXDPI == null ||
              screen.logicalXDPI == screen.deviceXDPI || !hasBadZoomedRects(measure))
              return rect;
          var scaleX = screen.logicalXDPI / screen.deviceXDPI;
          var scaleY = screen.logicalYDPI / screen.deviceYDPI;
          return {
              left: rect.left * scaleX, right: rect.right * scaleX,
              top: rect.top * scaleY, bottom: rect.bottom * scaleY
          };
      }
  
      function clearLineMeasurementCacheFor(lineView) {
          if (lineView.measure) {
              lineView.measure.cache = {};
              lineView.measure.heights = null;
              if (lineView.rest) for (var i = 0; i < lineView.rest.length; i++)
                  lineView.measure.caches[i] = {};
          }
      }
  
      function clearLineMeasurementCache(cm) {
          cm.display.externalMeasure = null;
          removeChildren(cm.display.lineMeasure);
          for (var i = 0; i < cm.display.view.length; i++)
              clearLineMeasurementCacheFor(cm.display.view[i]);
      }
  
      function clearCaches(cm) {
          clearLineMeasurementCache(cm);
          cm.display.cachedCharWidth = cm.display.cachedTextHeight = cm.display.cachedPaddingH = null;
          if (!cm.options.lineWrapping) cm.display.maxLineChanged = true;
          cm.display.lineNumChars = null;
      }
  
      function pageScrollX() {
          return window.pageXOffset || (document.documentElement || document.body).scrollLeft;
      }
  
      function pageScrollY() {
          return window.pageYOffset || (document.documentElement || document.body).scrollTop;
      }
  
      // Converts a {top, bottom, left, right} box from line-local
      // coordinates into another coordinate system. Context may be one of
      // "line", "div" (display.lineDiv), "local"/null (editor), "window",
      // or "page".
      function intoCoordSystem(cm, lineObj, rect, context) {
          if (lineObj.widgets) for (var i = 0; i < lineObj.widgets.length; ++i) if (lineObj.widgets[i].above) {
              var size = widgetHeight(lineObj.widgets[i]);
              rect.top += size;
              rect.bottom += size;
          }
          if (context == "line") return rect;
          if (!context) context = "local";
          var yOff = heightAtLine(lineObj);
          if (context == "local") yOff += paddingTop(cm.display);
          else yOff -= cm.display.viewOffset;
          if (context == "page" || context == "window") {
              var lOff = cm.display.lineSpace.getBoundingClientRect();
              yOff += lOff.top + (context == "window" ? 0 : pageScrollY());
              var xOff = lOff.left + (context == "window" ? 0 : pageScrollX());
              rect.left += xOff;
              rect.right += xOff;
          }
          rect.top += yOff;
          rect.bottom += yOff;
          return rect;
      }
  
      // Coverts a box from "div" coords to another coordinate system.
      // Context may be "window", "page", "div", or "local"/null.
      function fromCoordSystem(cm, coords, context) {
          if (context == "div") return coords;
          var left = coords.left, top = coords.top;
          // First move into "page" coordinate system
          if (context == "page") {
              left -= pageScrollX();
              top -= pageScrollY();
          } else if (context == "local" || !context) {
              var localBox = cm.display.sizer.getBoundingClientRect();
              left += localBox.left;
              top += localBox.top;
          }
  
          var lineSpaceBox = cm.display.lineSpace.getBoundingClientRect();
          return {left: left - lineSpaceBox.left, top: top - lineSpaceBox.top};
      }
  
      function charCoords(cm, pos, context, lineObj, bias) {
          if (!lineObj) lineObj = getLine(cm.doc, pos.line);
          return intoCoordSystem(cm, lineObj, measureChar(cm, lineObj, pos.ch, bias), context);
      }
  
      // Returns a box for a given cursor position, which may have an
      // 'other' property containing the position of the secondary cursor
      // on a bidi boundary.
      function cursorCoords(cm, pos, context, lineObj, preparedMeasure, varHeight) {
          lineObj = lineObj || getLine(cm.doc, pos.line);
          if (!preparedMeasure) preparedMeasure = prepareMeasureForLine(cm, lineObj);
          function get(ch, right) {
              var m = measureCharPrepared(cm, preparedMeasure, ch, right ? "right" : "left", varHeight);
              if (right) m.left = m.right; else m.right = m.left;
              return intoCoordSystem(cm, lineObj, m, context);
          }
  
          function getBidi(ch, partPos) {
              var part = order[partPos], right = part.level % 2;
              if (ch == bidiLeft(part) && partPos && part.level < order[partPos - 1].level) {
                  part = order[--partPos];
                  ch = bidiRight(part) - (part.level % 2 ? 0 : 1);
                  right = true;
              } else if (ch == bidiRight(part) && partPos < order.length - 1 && part.level < order[partPos + 1].level) {
                  part = order[++partPos];
                  ch = bidiLeft(part) - part.level % 2;
                  right = false;
              }
              if (right && ch == part.to && ch > part.from) return get(ch - 1);
              return get(ch, right);
          }
  
          var order = getOrder(lineObj), ch = pos.ch;
          if (!order) return get(ch);
          var partPos = getBidiPartAt(order, ch);
          var val = getBidi(ch, partPos);
          if (bidiOther != null) val.other = getBidi(ch, bidiOther);
          return val;
      }
  
      // Used to cheaply estimate the coordinates for a position. Used for
      // intermediate scroll updates.
      function estimateCoords(cm, pos) {
          var left = 0, pos = clipPos(cm.doc, pos);
          if (!cm.options.lineWrapping) left = charWidth(cm.display) * pos.ch;
          var lineObj = getLine(cm.doc, pos.line);
          var top = heightAtLine(lineObj) + paddingTop(cm.display);
          return {left: left, right: left, top: top, bottom: top + lineObj.height};
      }
  
      // Positions returned by coordsChar contain some extra information.
      // xRel is the relative x position of the input coordinates compared
      // to the found position (so xRel > 0 means the coordinates are to
      // the right of the character position, for example). When outside
      // is true, that means the coordinates lie outside the line's
      // vertical range.
      function PosWithInfo(line, ch, outside, xRel) {
          var pos = Pos(line, ch);
          pos.xRel = xRel;
          if (outside) pos.outside = true;
          return pos;
      }
  
      // Compute the character position closest to the given coordinates.
      // Input must be lineSpace-local ("div" coordinate system).
      function coordsChar(cm, x, y) {
          var doc = cm.doc;
          y += cm.display.viewOffset;
          if (y < 0) return PosWithInfo(doc.first, 0, true, -1);
          var lineN = lineAtHeight(doc, y), last = doc.first + doc.size - 1;
          if (lineN > last)
              return PosWithInfo(doc.first + doc.size - 1, getLine(doc, last).text.length, true, 1);
          if (x < 0) x = 0;
  
          var lineObj = getLine(doc, lineN);
          for (; ;) {
              var found = coordsCharInner(cm, lineObj, lineN, x, y);
              var merged = collapsedSpanAtEnd(lineObj);
              var mergedPos = merged && merged.find(0, true);
              if (merged && (found.ch > mergedPos.from.ch || found.ch == mergedPos.from.ch && found.xRel > 0))
                  lineN = lineNo(lineObj = mergedPos.to.line);
              else
                  return found;
          }
      }
  
      function coordsCharInner(cm, lineObj, lineNo, x, y) {
          var innerOff = y - heightAtLine(lineObj);
          var wrongLine = false, adjust = 2 * cm.display.wrapper.clientWidth;
          var preparedMeasure = prepareMeasureForLine(cm, lineObj);
  
          function getX(ch) {
              var sp = cursorCoords(cm, Pos(lineNo, ch), "line", lineObj, preparedMeasure);
              wrongLine = true;
              if (innerOff > sp.bottom) return sp.left - adjust;
              else if (innerOff < sp.top) return sp.left + adjust;
              else wrongLine = false;
              return sp.left;
          }
  
          var bidi = getOrder(lineObj), dist = lineObj.text.length;
          var from = lineLeft(lineObj), to = lineRight(lineObj);
          var fromX = getX(from), fromOutside = wrongLine, toX = getX(to), toOutside = wrongLine;
  
          if (x > toX) return PosWithInfo(lineNo, to, toOutside, 1);
          // Do a binary search between these bounds.
          for (; ;) {
              if (bidi ? to == from || to == moveVisually(lineObj, from, 1) : to - from <= 1) {
                  var ch = x < fromX || x - fromX <= toX - x ? from : to;
                  var xDiff = x - (ch == from ? fromX : toX);
                  while (isExtendingChar(lineObj.text.charAt(ch))) ++ch;
                  var pos = PosWithInfo(lineNo, ch, ch == from ? fromOutside : toOutside,
                      xDiff < -1 ? -1 : xDiff > 1 ? 1 : 0);
                  return pos;
              }
              var step = Math.ceil(dist / 2), middle = from + step;
              if (bidi) {
                  middle = from;
                  for (var i = 0; i < step; ++i) middle = moveVisually(lineObj, middle, 1);
              }
              var middleX = getX(middle);
              if (middleX > x) {
                  to = middle;
                  toX = middleX;
                  if (toOutside = wrongLine) toX += 1000;
                  dist = step;
              }
              else {
                  from = middle;
                  fromX = middleX;
                  fromOutside = wrongLine;
                  dist -= step;
              }
          }
      }
  
      var measureText;
      // Compute the default text height.
      function textHeight(display) {
          if (display.cachedTextHeight != null) return display.cachedTextHeight;
          if (measureText == null) {
              measureText = elt("pre");
              // Measure a bunch of lines, for browsers that compute
              // fractional heights.
              for (var i = 0; i < 49; ++i) {
                  measureText.appendChild(document.createTextNode("x"));
                  measureText.appendChild(elt("br"));
              }
              measureText.appendChild(document.createTextNode("x"));
          }
          removeChildrenAndAdd(display.measure, measureText);
          var height = measureText.offsetHeight / 50;
          if (height > 3) display.cachedTextHeight = height;
          removeChildren(display.measure);
          return height || 1;
      }
  
      // Compute the default character width.
      function charWidth(display) {
          if (display.cachedCharWidth != null) return display.cachedCharWidth;
          var anchor = elt("span", "xxxxxxxxxx");
          var pre = elt("pre", [anchor]);
          removeChildrenAndAdd(display.measure, pre);
          var rect = anchor.getBoundingClientRect(), width = (rect.right - rect.left) / 10;
          if (width > 2) display.cachedCharWidth = width;
          return width || 10;
      }
  
      // OPERATIONS
  
      // Operations are used to wrap a series of changes to the editor
      // state in such a way that each change won't have to update the
      // cursor and display (which would be awkward, slow, and
      // error-prone). Instead, display updates are batched and then all
      // combined and executed at once.
  
      var operationGroup = null;
  
      var nextOpId = 0;
      // Start a new operation.
      function startOperation(cm) {
          cm.curOp = {
              cm: cm,
              viewChanged: false,      // Flag that indicates that lines might need to be redrawn
              startHeight: cm.doc.height, // Used to detect need to update scrollbar
              forceUpdate: false,      // Used to force a redraw
              updateInput: null,       // Whether to reset the input textarea
              typing: false,           // Whether this reset should be careful to leave existing text (for compositing)
              changeObjs: null,        // Accumulated changes, for firing change events
              cursorActivityHandlers: null, // Set of handlers to fire cursorActivity on
              cursorActivityCalled: 0, // Tracks which cursorActivity handlers have been called already
              selectionChanged: false, // Whether the selection needs to be redrawn
              updateMaxLine: false,    // Set when the widest line needs to be determined anew
              scrollLeft: null, scrollTop: null, // Intermediate scroll position, not pushed to DOM yet
              scrollToPos: null,       // Used to scroll to a specific position
              id: ++nextOpId           // Unique ID
          };
          if (operationGroup) {
              operationGroup.ops.push(cm.curOp);
          } else {
              cm.curOp.ownsGroup = operationGroup = {
                  ops: [cm.curOp],
                  delayedCallbacks: []
              };
          }
      }
  
      function fireCallbacksForOps(group) {
          // Calls delayed callbacks and cursorActivity handlers until no
          // new ones appear
          var callbacks = group.delayedCallbacks, i = 0;
          do {
              for (; i < callbacks.length; i++)
                  callbacks[i]();
              for (var j = 0; j < group.ops.length; j++) {
                  var op = group.ops[j];
                  if (op.cursorActivityHandlers)
                      while (op.cursorActivityCalled < op.cursorActivityHandlers.length)
                          op.cursorActivityHandlers[op.cursorActivityCalled++](op.cm);
              }
          } while (i < callbacks.length);
      }
  
      // Finish an operation, updating the display and signalling delayed events
      function endOperation(cm) {
          var op = cm.curOp, group = op.ownsGroup;
          if (!group) return;
  
          try {
              fireCallbacksForOps(group);
          }
          finally {
              operationGroup = null;
              for (var i = 0; i < group.ops.length; i++)
                  group.ops[i].cm.curOp = null;
              endOperations(group);
          }
      }
  
      // The DOM updates done when an operation finishes are batched so
      // that the minimum number of relayouts are required.
      function endOperations(group) {
          var ops = group.ops;
          for (var i = 0; i < ops.length; i++) // Read DOM
              endOperation_R1(ops[i]);
          for (var i = 0; i < ops.length; i++) // Write DOM (maybe)
              endOperation_W1(ops[i]);
          for (var i = 0; i < ops.length; i++) // Read DOM
              endOperation_R2(ops[i]);
          for (var i = 0; i < ops.length; i++) // Write DOM (maybe)
              endOperation_W2(ops[i]);
          for (var i = 0; i < ops.length; i++) // Read DOM
              endOperation_finish(ops[i]);
      }
  
      function endOperation_R1(op) {
          var cm = op.cm, display = cm.display;
          maybeClipScrollbars(cm);
          if (op.updateMaxLine) findMaxLine(cm);
  
          op.mustUpdate = op.viewChanged || op.forceUpdate || op.scrollTop != null ||
              op.scrollToPos && (op.scrollToPos.from.line < display.viewFrom ||
              op.scrollToPos.to.line >= display.viewTo) ||
              display.maxLineChanged && cm.options.lineWrapping;
          op.update = op.mustUpdate &&
              new DisplayUpdate(cm, op.mustUpdate && {top: op.scrollTop, ensure: op.scrollToPos}, op.forceUpdate);
      }
  
      function endOperation_W1(op) {
          op.updatedDisplay = op.mustUpdate && updateDisplayIfNeeded(op.cm, op.update);
      }
  
      function endOperation_R2(op) {
          var cm = op.cm, display = cm.display;
          if (op.updatedDisplay) updateHeightsInViewport(cm);
  
          op.barMeasure = measureForScrollbars(cm);
  
          // If the max line changed since it was last measured, measure it,
          // and ensure the document's width matches it.
          // updateDisplay_W2 will use these properties to do the actual resizing
          if (display.maxLineChanged && !cm.options.lineWrapping) {
              op.adjustWidthTo = measureChar(cm, display.maxLine, display.maxLine.text.length).left + 3;
              cm.display.sizerWidth = op.adjustWidthTo;
              op.barMeasure.scrollWidth =
                  Math.max(display.scroller.clientWidth, display.sizer.offsetLeft + op.adjustWidthTo + scrollGap(cm) + cm.display.barWidth);
              op.maxScrollLeft = Math.max(0, display.sizer.offsetLeft + op.adjustWidthTo - displayWidth(cm));
          }
  
          if (op.updatedDisplay || op.selectionChanged)
              op.preparedSelection = display.input.prepareSelection();
      }
  
      function endOperation_W2(op) {
          var cm = op.cm;
  
          if (op.adjustWidthTo != null) {
              cm.display.sizer.style.minWidth = op.adjustWidthTo + "px";
              if (op.maxScrollLeft < cm.doc.scrollLeft)
                  setScrollLeft(cm, Math.min(cm.display.scroller.scrollLeft, op.maxScrollLeft), true);
              cm.display.maxLineChanged = false;
          }
  
          if (op.preparedSelection)
              cm.display.input.showSelection(op.preparedSelection);
          if (op.updatedDisplay)
              setDocumentHeight(cm, op.barMeasure);
          if (op.updatedDisplay || op.startHeight != cm.doc.height)
              updateScrollbars(cm, op.barMeasure);
  
          if (op.selectionChanged) restartBlink(cm);
  
          if (cm.state.focused && op.updateInput)
              cm.display.input.reset(op.typing);
      }
  
      function endOperation_finish(op) {
          var cm = op.cm, display = cm.display, doc = cm.doc;
  
          if (op.updatedDisplay) postUpdateDisplay(cm, op.update);
  
          // Abort mouse wheel delta measurement, when scrolling explicitly
          if (display.wheelStartX != null && (op.scrollTop != null || op.scrollLeft != null || op.scrollToPos))
              display.wheelStartX = display.wheelStartY = null;
  
          // Propagate the scroll position to the actual DOM scroller
          if (op.scrollTop != null && (display.scroller.scrollTop != op.scrollTop || op.forceScroll)) {
              doc.scrollTop = Math.max(0, Math.min(display.scroller.scrollHeight - display.scroller.clientHeight, op.scrollTop));
              display.scrollbars.setScrollTop(doc.scrollTop);
              display.scroller.scrollTop = doc.scrollTop;
          }
          if (op.scrollLeft != null && (display.scroller.scrollLeft != op.scrollLeft || op.forceScroll)) {
              doc.scrollLeft = Math.max(0, Math.min(display.scroller.scrollWidth - displayWidth(cm), op.scrollLeft));
              display.scrollbars.setScrollLeft(doc.scrollLeft);
              display.scroller.scrollLeft = doc.scrollLeft;
              alignHorizontally(cm);
          }
          // If we need to scroll a specific position into view, do so.
          if (op.scrollToPos) {
              var coords = scrollPosIntoView(cm, clipPos(doc, op.scrollToPos.from),
                  clipPos(doc, op.scrollToPos.to), op.scrollToPos.margin);
              if (op.scrollToPos.isCursor && cm.state.focused) maybeScrollWindow(cm, coords);
          }
  
          // Fire events for markers that are hidden/unidden by editing or
          // undoing
          var hidden = op.maybeHiddenMarkers, unhidden = op.maybeUnhiddenMarkers;
          if (hidden) for (var i = 0; i < hidden.length; ++i)
              if (!hidden[i].lines.length) signal(hidden[i], "hide");
          if (unhidden) for (var i = 0; i < unhidden.length; ++i)
              if (unhidden[i].lines.length) signal(unhidden[i], "unhide");
  
          if (display.wrapper.offsetHeight)
              doc.scrollTop = cm.display.scroller.scrollTop;
  
          // Fire change events, and delayed event handlers
          if (op.changeObjs)
              signal(cm, "changes", cm, op.changeObjs);
          if (op.update)
              op.update.finish();
      }
  
      // Run the given function in an operation
      function runInOp(cm, f) {
          if (cm.curOp) return f();
          startOperation(cm);
          try {
              return f();
          }
          finally {
              endOperation(cm);
          }
      }
  
      // Wraps a function in an operation. Returns the wrapped function.
      function operation(cm, f) {
          return function () {
              if (cm.curOp) return f.apply(cm, arguments);
              startOperation(cm);
              try {
                  return f.apply(cm, arguments);
              }
              finally {
                  endOperation(cm);
              }
          };
      }
  
      // Used to add methods to editor and doc instances, wrapping them in
      // operations.
      function methodOp(f) {
          return function () {
              if (this.curOp) return f.apply(this, arguments);
              startOperation(this);
              try {
                  return f.apply(this, arguments);
              }
              finally {
                  endOperation(this);
              }
          };
      }
  
      function docMethodOp(f) {
          return function () {
              var cm = this.cm;
              if (!cm || cm.curOp) return f.apply(this, arguments);
              startOperation(cm);
              try {
                  return f.apply(this, arguments);
              }
              finally {
                  endOperation(cm);
              }
          };
      }
  
      // VIEW TRACKING
  
      // These objects are used to represent the visible (currently drawn)
      // part of the document. A LineView may correspond to multiple
      // logical lines, if those are connected by collapsed ranges.
      function LineView(doc, line, lineN) {
          // The starting line
          this.line = line;
          // Continuing lines, if any
          this.rest = visualLineContinued(line);
          // Number of logical lines in this visual line
          this.size = this.rest ? lineNo(lst(this.rest)) - lineN + 1 : 1;
          this.node = this.text = null;
          this.hidden = lineIsHidden(doc, line);
      }
  
      // Create a range of LineView objects for the given lines.
      function buildViewArray(cm, from, to) {
          var array = [], nextPos;
          for (var pos = from; pos < to; pos = nextPos) {
              var view = new LineView(cm.doc, getLine(cm.doc, pos), pos);
              nextPos = pos + view.size;
              array.push(view);
          }
          return array;
      }
  
      // Updates the display.view data structure for a given change to the
      // document. From and to are in pre-change coordinates. Lendiff is
      // the amount of lines added or subtracted by the change. This is
      // used for changes that span multiple lines, or change the way
      // lines are divided into visual lines. regLineChange (below)
      // registers single-line changes.
      function regChange(cm, from, to, lendiff) {
          if (from == null) from = cm.doc.first;
          if (to == null) to = cm.doc.first + cm.doc.size;
          if (!lendiff) lendiff = 0;
  
          var display = cm.display;
          if (lendiff && to < display.viewTo &&
              (display.updateLineNumbers == null || display.updateLineNumbers > from))
              display.updateLineNumbers = from;
  
          cm.curOp.viewChanged = true;
  
          if (from >= display.viewTo) { // Change after
              if (sawCollapsedSpans && visualLineNo(cm.doc, from) < display.viewTo)
                  resetView(cm);
          } else if (to <= display.viewFrom) { // Change before
              if (sawCollapsedSpans && visualLineEndNo(cm.doc, to + lendiff) > display.viewFrom) {
                  resetView(cm);
              } else {
                  display.viewFrom += lendiff;
                  display.viewTo += lendiff;
              }
          } else if (from <= display.viewFrom && to >= display.viewTo) { // Full overlap
              resetView(cm);
          } else if (from <= display.viewFrom) { // Top overlap
              var cut = viewCuttingPoint(cm, to, to + lendiff, 1);
              if (cut) {
                  display.view = display.view.slice(cut.index);
                  display.viewFrom = cut.lineN;
                  display.viewTo += lendiff;
              } else {
                  resetView(cm);
              }
          } else if (to >= display.viewTo) { // Bottom overlap
              var cut = viewCuttingPoint(cm, from, from, -1);
              if (cut) {
                  display.view = display.view.slice(0, cut.index);
                  display.viewTo = cut.lineN;
              } else {
                  resetView(cm);
              }
          } else { // Gap in the middle
              var cutTop = viewCuttingPoint(cm, from, from, -1);
              var cutBot = viewCuttingPoint(cm, to, to + lendiff, 1);
              if (cutTop && cutBot) {
                  display.view = display.view.slice(0, cutTop.index)
                      .concat(buildViewArray(cm, cutTop.lineN, cutBot.lineN))
                      .concat(display.view.slice(cutBot.index));
                  display.viewTo += lendiff;
              } else {
                  resetView(cm);
              }
          }
  
          var ext = display.externalMeasured;
          if (ext) {
              if (to < ext.lineN)
                  ext.lineN += lendiff;
              else if (from < ext.lineN + ext.size)
                  display.externalMeasured = null;
          }
      }
  
      // Register a change to a single line. Type must be one of "text",
      // "gutter", "class", "widget"
      function regLineChange(cm, line, type) {
          cm.curOp.viewChanged = true;
          var display = cm.display, ext = cm.display.externalMeasured;
          if (ext && line >= ext.lineN && line < ext.lineN + ext.size)
              display.externalMeasured = null;
  
          if (line < display.viewFrom || line >= display.viewTo) return;
          var lineView = display.view[findViewIndex(cm, line)];
          if (lineView.node == null) return;
          var arr = lineView.changes || (lineView.changes = []);
          if (indexOf(arr, type) == -1) arr.push(type);
      }
  
      // Clear the view.
      function resetView(cm) {
          cm.display.viewFrom = cm.display.viewTo = cm.doc.first;
          cm.display.view = [];
          cm.display.viewOffset = 0;
      }
  
      // Find the view element corresponding to a given line. Return null
      // when the line isn't visible.
      function findViewIndex(cm, n) {
          if (n >= cm.display.viewTo) return null;
          n -= cm.display.viewFrom;
          if (n < 0) return null;
          var view = cm.display.view;
          for (var i = 0; i < view.length; i++) {
              n -= view[i].size;
              if (n < 0) return i;
          }
      }
  
      function viewCuttingPoint(cm, oldN, newN, dir) {
          var index = findViewIndex(cm, oldN), diff, view = cm.display.view;
          if (!sawCollapsedSpans || newN == cm.doc.first + cm.doc.size)
              return {index: index, lineN: newN};
          for (var i = 0, n = cm.display.viewFrom; i < index; i++)
              n += view[i].size;
          if (n != oldN) {
              if (dir > 0) {
                  if (index == view.length - 1) return null;
                  diff = (n + view[index].size) - oldN;
                  index++;
              } else {
                  diff = n - oldN;
              }
              oldN += diff;
              newN += diff;
          }
          while (visualLineNo(cm.doc, newN) != newN) {
              if (index == (dir < 0 ? 0 : view.length - 1)) return null;
              newN += dir * view[index - (dir < 0 ? 1 : 0)].size;
              index += dir;
          }
          return {index: index, lineN: newN};
      }
  
      // Force the view to cover a given range, adding empty view element
      // or clipping off existing ones as needed.
      function adjustView(cm, from, to) {
          var display = cm.display, view = display.view;
          if (view.length == 0 || from >= display.viewTo || to <= display.viewFrom) {
              display.view = buildViewArray(cm, from, to);
              display.viewFrom = from;
          } else {
              if (display.viewFrom > from)
                  display.view = buildViewArray(cm, from, display.viewFrom).concat(display.view);
              else if (display.viewFrom < from)
                  display.view = display.view.slice(findViewIndex(cm, from));
              display.viewFrom = from;
              if (display.viewTo < to)
                  display.view = display.view.concat(buildViewArray(cm, display.viewTo, to));
              else if (display.viewTo > to)
                  display.view = display.view.slice(0, findViewIndex(cm, to));
          }
          display.viewTo = to;
      }
  
      // Count the number of lines in the view whose DOM representation is
      // out of date (or nonexistent).
      function countDirtyView(cm) {
          var view = cm.display.view, dirty = 0;
          for (var i = 0; i < view.length; i++) {
              var lineView = view[i];
              if (!lineView.hidden && (!lineView.node || lineView.changes)) ++dirty;
          }
          return dirty;
      }
  
      // EVENT HANDLERS
  
      // Attach the necessary event handlers when initializing the editor
      function registerEventHandlers(cm) {
          var d = cm.display;
          on(d.scroller, "mousedown", operation(cm, onMouseDown));
          // Older IE's will not fire a second mousedown for a double click
          if (ie && ie_version < 11)
              on(d.scroller, "dblclick", operation(cm, function (e) {
                  if (signalDOMEvent(cm, e)) return;
                  var pos = posFromMouse(cm, e);
                  if (!pos || clickInGutter(cm, e) || eventInWidget(cm.display, e)) return;
                  e_preventDefault(e);
                  var word = cm.findWordAt(pos);
                  extendSelection(cm.doc, word.anchor, word.head);
              }));
          else
              on(d.scroller, "dblclick", function (e) {
                  signalDOMEvent(cm, e) || e_preventDefault(e);
              });
          // Some browsers fire contextmenu *after* opening the menu, at
          // which point we can't mess with it anymore. Context menu is
          // handled in onMouseDown for these browsers.
          if (!captureRightClick) on(d.scroller, "contextmenu", function (e) {
              onContextMenu(cm, e);
          });
  
          // Used to suppress mouse event handling when a touch happens
          var touchFinished, prevTouch = {end: 0};
  
          function finishTouch() {
              if (d.activeTouch) {
                  touchFinished = setTimeout(function () {
                      d.activeTouch = null;
                  }, 1000);
                  prevTouch = d.activeTouch;
                  prevTouch.end = +new Date;
              }
          };
          function isMouseLikeTouchEvent(e) {
              if (e.touches.length != 1) return false;
              var touch = e.touches[0];
              return touch.radiusX <= 1 && touch.radiusY <= 1;
          }
  
          function farAway(touch, other) {
              if (other.left == null) return true;
              var dx = other.left - touch.left, dy = other.top - touch.top;
              return dx * dx + dy * dy > 20 * 20;
          }
  
          on(d.scroller, "touchstart", function (e) {
              if (!isMouseLikeTouchEvent(e)) {
                  clearTimeout(touchFinished);
                  var now = +new Date;
                  d.activeTouch = {
                      start: now, moved: false,
                      prev: now - prevTouch.end <= 300 ? prevTouch : null
                  };
                  if (e.touches.length == 1) {
                      d.activeTouch.left = e.touches[0].pageX;
                      d.activeTouch.top = e.touches[0].pageY;
                  }
              }
          });
          on(d.scroller, "touchmove", function () {
              if (d.activeTouch) d.activeTouch.moved = true;
          });
          on(d.scroller, "touchend", function (e) {
              var touch = d.activeTouch;
              if (touch && !eventInWidget(d, e) && touch.left != null &&
                  !touch.moved && new Date - touch.start < 300) {
                  var pos = cm.coordsChar(d.activeTouch, "page"), range;
                  if (!touch.prev || farAway(touch, touch.prev)) // Single tap
                      range = new Range(pos, pos);
                  else if (!touch.prev.prev || farAway(touch, touch.prev.prev)) // Double tap
                      range = cm.findWordAt(pos);
                  else // Triple tap
                      range = new Range(Pos(pos.line, 0), clipPos(cm.doc, Pos(pos.line + 1, 0)));
                  cm.setSelection(range.anchor, range.head);
                  cm.focus();
                  e_preventDefault(e);
              }
              finishTouch();
          });
          on(d.scroller, "touchcancel", finishTouch);
  
          // Sync scrolling between fake scrollbars and real scrollable
          // area, ensure viewport is updated when scrolling.
          on(d.scroller, "scroll", function () {
              if (d.scroller.clientHeight) {
                  setScrollTop(cm, d.scroller.scrollTop);
                  setScrollLeft(cm, d.scroller.scrollLeft, true);
                  signal(cm, "scroll", cm);
              }
          });
  
          // Listen to wheel events in order to try and update the viewport on time.
          on(d.scroller, "mousewheel", function (e) {
              onScrollWheel(cm, e);
          });
          on(d.scroller, "DOMMouseScroll", function (e) {
              onScrollWheel(cm, e);
          });
  
          // Prevent wrapper from ever scrolling
          on(d.wrapper, "scroll", function () {
              d.wrapper.scrollTop = d.wrapper.scrollLeft = 0;
          });
  
          function drag_(e) {
              if (!signalDOMEvent(cm, e)) e_stop(e);
          }
  
          if (cm.options.dragDrop) {
              on(d.scroller, "dragstart", function (e) {
                  onDragStart(cm, e);
              });
              on(d.scroller, "dragenter", drag_);
              on(d.scroller, "dragover", drag_);
              on(d.scroller, "drop", operation(cm, onDrop));
          }
  
          var inp = d.input.getField();
          on(inp, "keyup", function (e) {
              onKeyUp.call(cm, e);
          });
          on(inp, "keydown", operation(cm, onKeyDown));
          on(inp, "keypress", operation(cm, onKeyPress));
          on(inp, "focus", bind(onFocus, cm));
          on(inp, "blur", bind(onBlur, cm));
      }
  
      // Called when the window resizes
      function onResize(cm) {
          var d = cm.display;
          if (d.lastWrapHeight == d.wrapper.clientHeight && d.lastWrapWidth == d.wrapper.clientWidth)
              return;
          // Might be a text scaling operation, clear size caches.
          d.cachedCharWidth = d.cachedTextHeight = d.cachedPaddingH = null;
          d.scrollbarsClipped = false;
          cm.setSize();
      }
  
      // MOUSE EVENTS
  
      // Return true when the given mouse event happened in a widget
      function eventInWidget(display, e) {
          for (var n = e_target(e); n != display.wrapper; n = n.parentNode) {
              if (!n || (n.nodeType == 1 && n.getAttribute("cm-ignore-events") == "true") ||
                  (n.parentNode == display.sizer && n != display.mover))
                  return true;
          }
      }
  
      // Given a mouse event, find the corresponding position. If liberal
      // is false, it checks whether a gutter or scrollbar was clicked,
      // and returns null if it was. forRect is used by rectangular
      // selections, and tries to estimate a character position even for
      // coordinates beyond the right of the text.
      function posFromMouse(cm, e, liberal, forRect) {
          var display = cm.display;
          if (!liberal && e_target(e).getAttribute("cm-not-content") == "true") return null;
  
          var x, y, space = display.lineSpace.getBoundingClientRect();
          // Fails unpredictably on IE[67] when mouse is dragged around quickly.
          try {
              x = e.clientX - space.left;
              y = e.clientY - space.top;
          }
          catch (e) {
              return null;
          }
          var coords = coordsChar(cm, x, y), line;
          if (forRect && coords.xRel == 1 && (line = getLine(cm.doc, coords.line).text).length == coords.ch) {
              var colDiff = countColumn(line, line.length, cm.options.tabSize) - line.length;
              coords = Pos(coords.line, Math.max(0, Math.round((x - paddingH(cm.display).left) / charWidth(cm.display)) - colDiff));
          }
          return coords;
      }
  
      // A mouse down can be a single click, double click, triple click,
      // start of selection drag, start of text drag, new cursor
      // (ctrl-click), rectangle drag (alt-drag), or xwin
      // middle-click-paste. Or it might be a click on something we should
      // not interfere with, such as a scrollbar or widget.
      function onMouseDown(e) {
          var cm = this, display = cm.display;
          if (display.activeTouch && display.input.supportsTouch() || signalDOMEvent(cm, e)) return;
          display.shift = e.shiftKey;
  
          if (eventInWidget(display, e)) {
              if (!webkit) {
                  // Briefly turn off draggability, to allow widgets to do
                  // normal dragging things.
                  display.scroller.draggable = false;
                  setTimeout(function () {
                      display.scroller.draggable = true;
                  }, 100);
              }
              return;
          }
          if (clickInGutter(cm, e)) return;
          var start = posFromMouse(cm, e);
          window.focus();
  
          switch (e_button(e)) {
              case 1:
                  if (start)
                      leftButtonDown(cm, e, start);
                  else if (e_target(e) == display.scroller)
                      e_preventDefault(e);
                  break;
              case 2:
                  if (webkit) cm.state.lastMiddleDown = +new Date;
                  if (start) extendSelection(cm.doc, start);
                  setTimeout(function () {
                      display.input.focus();
                  }, 20);
                  e_preventDefault(e);
                  break;
              case 3:
                  if (captureRightClick) onContextMenu(cm, e);
                  break;
          }
      }
  
      var lastClick, lastDoubleClick;
  
      function leftButtonDown(cm, e, start) {
          if (ie) setTimeout(bind(ensureFocus, cm), 0);
          else ensureFocus(cm);
  
          var now = +new Date, type;
          if (lastDoubleClick && lastDoubleClick.time > now - 400 && cmp(lastDoubleClick.pos, start) == 0) {
              type = "triple";
          } else if (lastClick && lastClick.time > now - 400 && cmp(lastClick.pos, start) == 0) {
              type = "double";
              lastDoubleClick = {time: now, pos: start};
          } else {
              type = "single";
              lastClick = {time: now, pos: start};
          }
  
          var sel = cm.doc.sel, modifier = mac ? e.metaKey : e.ctrlKey, contained;
          if (cm.options.dragDrop && dragAndDrop && !isReadOnly(cm) &&
              type == "single" && (contained = sel.contains(start)) > -1 &&
              !sel.ranges[contained].empty())
              leftButtonStartDrag(cm, e, start, modifier);
          else
              leftButtonSelect(cm, e, start, type, modifier);
      }
  
      // Start a text drag. When it ends, see if any dragging actually
      // happen, and treat as a click if it didn't.
      function leftButtonStartDrag(cm, e, start, modifier) {
          var display = cm.display;
          var dragEnd = operation(cm, function (e2) {
              if (webkit) display.scroller.draggable = false;
              cm.state.draggingText = false;
              off(document, "mouseup", dragEnd);
              off(display.scroller, "drop", dragEnd);
              if (Math.abs(e.clientX - e2.clientX) + Math.abs(e.clientY - e2.clientY) < 10) {
                  e_preventDefault(e2);
                  if (!modifier)
                      extendSelection(cm.doc, start);
                  display.input.focus();
                  // Work around unexplainable focus problem in IE9 (#2127)
                  if (ie && ie_version == 9)
                      setTimeout(function () {
                          document.body.focus();
                          display.input.focus();
                      }, 20);
              }
          });
          // Let the drag handler handle this.
          if (webkit) display.scroller.draggable = true;
          cm.state.draggingText = dragEnd;
          // IE's approach to draggable
          if (display.scroller.dragDrop) display.scroller.dragDrop();
          on(document, "mouseup", dragEnd);
          on(display.scroller, "drop", dragEnd);
      }
  
      // Normal selection, as opposed to text dragging.
      function leftButtonSelect(cm, e, start, type, addNew) {
          var display = cm.display, doc = cm.doc;
          e_preventDefault(e);
  
          var ourRange, ourIndex, startSel = doc.sel, ranges = startSel.ranges;
          if (addNew && !e.shiftKey) {
              ourIndex = doc.sel.contains(start);
              if (ourIndex > -1)
                  ourRange = ranges[ourIndex];
              else
                  ourRange = new Range(start, start);
          } else {
              ourRange = doc.sel.primary();
          }
  
          if (e.altKey) {
              type = "rect";
              if (!addNew) ourRange = new Range(start, start);
              start = posFromMouse(cm, e, true, true);
              ourIndex = -1;
          } else if (type == "double") {
              var word = cm.findWordAt(start);
              if (cm.display.shift || doc.extend)
                  ourRange = extendRange(doc, ourRange, word.anchor, word.head);
              else
                  ourRange = word;
          } else if (type == "triple") {
              var line = new Range(Pos(start.line, 0), clipPos(doc, Pos(start.line + 1, 0)));
              if (cm.display.shift || doc.extend)
                  ourRange = extendRange(doc, ourRange, line.anchor, line.head);
              else
                  ourRange = line;
          } else {
              ourRange = extendRange(doc, ourRange, start);
          }
  
          if (!addNew) {
              ourIndex = 0;
              setSelection(doc, new Selection([ourRange], 0), sel_mouse);
              startSel = doc.sel;
          } else if (ourIndex == -1) {
              ourIndex = ranges.length;
              setSelection(doc, normalizeSelection(ranges.concat([ourRange]), ourIndex),
                  {scroll: false, origin: "*mouse"});
          } else if (ranges.length > 1 && ranges[ourIndex].empty() && type == "single") {
              setSelection(doc, normalizeSelection(ranges.slice(0, ourIndex).concat(ranges.slice(ourIndex + 1)), 0));
              startSel = doc.sel;
          } else {
              replaceOneSelection(doc, ourIndex, ourRange, sel_mouse);
          }
  
          var lastPos = start;
  
          function extendTo(pos) {
              if (cmp(lastPos, pos) == 0) return;
              lastPos = pos;
  
              if (type == "rect") {
                  var ranges = [], tabSize = cm.options.tabSize;
                  var startCol = countColumn(getLine(doc, start.line).text, start.ch, tabSize);
                  var posCol = countColumn(getLine(doc, pos.line).text, pos.ch, tabSize);
                  var left = Math.min(startCol, posCol), right = Math.max(startCol, posCol);
                  for (var line = Math.min(start.line, pos.line), end = Math.min(cm.lastLine(), Math.max(start.line, pos.line));
                       line <= end; line++) {
                      var text = getLine(doc, line).text, leftPos = findColumn(text, left, tabSize);
                      if (left == right)
                          ranges.push(new Range(Pos(line, leftPos), Pos(line, leftPos)));
                      else if (text.length > leftPos)
                          ranges.push(new Range(Pos(line, leftPos), Pos(line, findColumn(text, right, tabSize))));
                  }
                  if (!ranges.length) ranges.push(new Range(start, start));
                  setSelection(doc, normalizeSelection(startSel.ranges.slice(0, ourIndex).concat(ranges), ourIndex),
                      {origin: "*mouse", scroll: false});
                  cm.scrollIntoView(pos);
              } else {
                  var oldRange = ourRange;
                  var anchor = oldRange.anchor, head = pos;
                  if (type != "single") {
                      if (type == "double")
                          var range = cm.findWordAt(pos);
                      else
                          var range = new Range(Pos(pos.line, 0), clipPos(doc, Pos(pos.line + 1, 0)));
                      if (cmp(range.anchor, anchor) > 0) {
                          head = range.head;
                          anchor = minPos(oldRange.from(), range.anchor);
                      } else {
                          head = range.anchor;
                          anchor = maxPos(oldRange.to(), range.head);
                      }
                  }
                  var ranges = startSel.ranges.slice(0);
                  ranges[ourIndex] = new Range(clipPos(doc, anchor), head);
                  setSelection(doc, normalizeSelection(ranges, ourIndex), sel_mouse);
              }
          }
  
          var editorSize = display.wrapper.getBoundingClientRect();
          // Used to ensure timeout re-tries don't fire when another extend
          // happened in the meantime (clearTimeout isn't reliable -- at
          // least on Chrome, the timeouts still happen even when cleared,
          // if the clear happens after their scheduled firing time).
          var counter = 0;
  
          function extend(e) {
              var curCount = ++counter;
              var cur = posFromMouse(cm, e, true, type == "rect");
              if (!cur) return;
              if (cmp(cur, lastPos) != 0) {
                  ensureFocus(cm);
                  extendTo(cur);
                  var visible = visibleLines(display, doc);
                  if (cur.line >= visible.to || cur.line < visible.from)
                      setTimeout(operation(cm, function () {
                          if (counter == curCount) extend(e);
                      }), 150);
              } else {
                  var outside = e.clientY < editorSize.top ? -20 : e.clientY > editorSize.bottom ? 20 : 0;
                  if (outside) setTimeout(operation(cm, function () {
                      if (counter != curCount) return;
                      display.scroller.scrollTop += outside;
                      extend(e);
                  }), 50);
              }
          }
  
          function done(e) {
              counter = Infinity;
              e_preventDefault(e);
              display.input.focus();
              off(document, "mousemove", move);
              off(document, "mouseup", up);
              doc.history.lastSelOrigin = null;
          }
  
          var move = operation(cm, function (e) {
              if (!e_button(e)) done(e);
              else extend(e);
          });
          var up = operation(cm, done);
          on(document, "mousemove", move);
          on(document, "mouseup", up);
      }
  
      // Determines whether an event happened in the gutter, and fires the
      // handlers for the corresponding event.
      function gutterEvent(cm, e, type, prevent, signalfn) {
          try {
              var mX = e.clientX, mY = e.clientY;
          }
          catch (e) {
              return false;
          }
          if (mX >= Math.floor(cm.display.gutters.getBoundingClientRect().right)) return false;
          if (prevent) e_preventDefault(e);
  
          var display = cm.display;
          var lineBox = display.lineDiv.getBoundingClientRect();
  
          if (mY > lineBox.bottom || !hasHandler(cm, type)) return e_defaultPrevented(e);
          mY -= lineBox.top - display.viewOffset;
  
          for (var i = 0; i < cm.options.gutters.length; ++i) {
              var g = display.gutters.childNodes[i];
              if (g && g.getBoundingClientRect().right >= mX) {
                  var line = lineAtHeight(cm.doc, mY);
                  var gutter = cm.options.gutters[i];
                  signalfn(cm, type, cm, line, gutter, e);
                  return e_defaultPrevented(e);
              }
          }
      }
  
      function clickInGutter(cm, e) {
          return gutterEvent(cm, e, "gutterClick", true, signalLater);
      }
  
      // Kludge to work around strange IE behavior where it'll sometimes
      // re-fire a series of drag-related events right after the drop (#1551)
      var lastDrop = 0;
  
      function onDrop(e) {
          var cm = this;
          if (signalDOMEvent(cm, e) || eventInWidget(cm.display, e))
              return;
          e_preventDefault(e);
          if (ie) lastDrop = +new Date;
          var pos = posFromMouse(cm, e, true), files = e.dataTransfer.files;
          if (!pos || isReadOnly(cm)) return;
          // Might be a file drop, in which case we simply extract the text
          // and insert it.
          if (files && files.length && window.FileReader && window.File) {
              var n = files.length, text = Array(n), read = 0;
              var loadFile = function (file, i) {
                  var reader = new FileReader;
                  reader.onload = operation(cm, function () {
                      text[i] = reader.result;
                      if (++read == n) {
                          pos = clipPos(cm.doc, pos);
                          var change = {from: pos, to: pos, text: splitLines(text.join("\n")), origin: "paste"};
                          makeChange(cm.doc, change);
                          setSelectionReplaceHistory(cm.doc, simpleSelection(pos, changeEnd(change)));
                      }
                  });
                  reader.readAsText(file);
              };
              for (var i = 0; i < n; ++i) loadFile(files[i], i);
          } else { // Normal drop
              // Don't do a replace if the drop happened inside of the selected text.
              if (cm.state.draggingText && cm.doc.sel.contains(pos) > -1) {
                  cm.state.draggingText(e);
                  // Ensure the editor is re-focused
                  setTimeout(function () {
                      cm.display.input.focus();
                  }, 20);
                  return;
              }
              try {
                  var text = e.dataTransfer.getData("Text");
                  if (text) {
                      if (cm.state.draggingText && !(mac ? e.metaKey : e.ctrlKey))
                          var selected = cm.listSelections();
                      setSelectionNoUndo(cm.doc, simpleSelection(pos, pos));
                      if (selected) for (var i = 0; i < selected.length; ++i)
                          replaceRange(cm.doc, "", selected[i].anchor, selected[i].head, "drag");
                      cm.replaceSelection(text, "around", "paste");
                      cm.display.input.focus();
                  }
              }
              catch (e) {
              }
          }
      }
  
      function onDragStart(cm, e) {
          if (ie && (!cm.state.draggingText || +new Date - lastDrop < 100)) {
              e_stop(e);
              return;
          }
          if (signalDOMEvent(cm, e) || eventInWidget(cm.display, e)) return;
  
          e.dataTransfer.setData("Text", cm.getSelection());
  
          // Use dummy image instead of default browsers image.
          // Recent Safari (~6.0.2) have a tendency to segfault when this happens, so we don't do it there.
          if (e.dataTransfer.setDragImage && !safari) {
              var img = elt("img", null, null, "position: fixed; left: 0; top: 0;");
              img.src = "data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==";
              if (presto) {
                  img.width = img.height = 1;
                  cm.display.wrapper.appendChild(img);
                  // Force a relayout, or Opera won't use our image for some obscure reason
                  img._top = img.offsetTop;
              }
              e.dataTransfer.setDragImage(img, 0, 0);
              if (presto) img.parentNode.removeChild(img);
          }
      }
  
      // SCROLL EVENTS
  
      // Sync the scrollable area and scrollbars, ensure the viewport
      // covers the visible area.
      function setScrollTop(cm, val) {
          if (Math.abs(cm.doc.scrollTop - val) < 2) return;
          cm.doc.scrollTop = val;
          if (!gecko) updateDisplaySimple(cm, {top: val});
          if (cm.display.scroller.scrollTop != val) cm.display.scroller.scrollTop = val;
          cm.display.scrollbars.setScrollTop(val);
          if (gecko) updateDisplaySimple(cm);
          startWorker(cm, 100);
      }
  
      // Sync scroller and scrollbar, ensure the gutter elements are
      // aligned.
      function setScrollLeft(cm, val, isScroller) {
          if (isScroller ? val == cm.doc.scrollLeft : Math.abs(cm.doc.scrollLeft - val) < 2) return;
          val = Math.min(val, cm.display.scroller.scrollWidth - cm.display.scroller.clientWidth);
          cm.doc.scrollLeft = val;
          alignHorizontally(cm);
          if (cm.display.scroller.scrollLeft != val) cm.display.scroller.scrollLeft = val;
          cm.display.scrollbars.setScrollLeft(val);
      }
  
      // Since the delta values reported on mouse wheel events are
      // unstandardized between browsers and even browser versions, and
      // generally horribly unpredictable, this code starts by measuring
      // the scroll effect that the first few mouse wheel events have,
      // and, from that, detects the way it can convert deltas to pixel
      // offsets afterwards.
      //
      // The reason we want to know the amount a wheel event will scroll
      // is that it gives us a chance to update the display before the
      // actual scrolling happens, reducing flickering.
  
      var wheelSamples = 0, wheelPixelsPerUnit = null;
      // Fill in a browser-detected starting value on browsers where we
      // know one. These don't have to be accurate -- the result of them
      // being wrong would just be a slight flicker on the first wheel
      // scroll (if it is large enough).
      if (ie) wheelPixelsPerUnit = -.53;
      else if (gecko) wheelPixelsPerUnit = 15;
      else if (chrome) wheelPixelsPerUnit = -.7;
      else if (safari) wheelPixelsPerUnit = -1 / 3;
  
      var wheelEventDelta = function (e) {
          var dx = e.wheelDeltaX, dy = e.wheelDeltaY;
          if (dx == null && e.detail && e.axis == e.HORIZONTAL_AXIS) dx = e.detail;
          if (dy == null && e.detail && e.axis == e.VERTICAL_AXIS) dy = e.detail;
          else if (dy == null) dy = e.wheelDelta;
          return {x: dx, y: dy};
      };
      CodeMirror.wheelEventPixels = function (e) {
          var delta = wheelEventDelta(e);
          delta.x *= wheelPixelsPerUnit;
          delta.y *= wheelPixelsPerUnit;
          return delta;
      };
  
      function onScrollWheel(cm, e) {
          var delta = wheelEventDelta(e), dx = delta.x, dy = delta.y;
  
          var display = cm.display, scroll = display.scroller;
          // Quit if there's nothing to scroll here
          if (!(dx && scroll.scrollWidth > scroll.clientWidth ||
              dy && scroll.scrollHeight > scroll.clientHeight)) return;
  
          // Webkit browsers on OS X abort momentum scrolls when the target
          // of the scroll event is removed from the scrollable element.
          // This hack (see related code in patchDisplay) makes sure the
          // element is kept around.
          if (dy && mac && webkit) {
              outer: for (var cur = e.target, view = display.view; cur != scroll; cur = cur.parentNode) {
                  for (var i = 0; i < view.length; i++) {
                      if (view[i].node == cur) {
                          cm.display.currentWheelTarget = cur;
                          break outer;
                      }
                  }
              }
          }
  
          // On some browsers, horizontal scrolling will cause redraws to
          // happen before the gutter has been realigned, causing it to
          // wriggle around in a most unseemly way. When we have an
          // estimated pixels/delta value, we just handle horizontal
          // scrolling entirely here. It'll be slightly off from native, but
          // better than glitching out.
          if (dx && !gecko && !presto && wheelPixelsPerUnit != null) {
              if (dy)
                  setScrollTop(cm, Math.max(0, Math.min(scroll.scrollTop + dy * wheelPixelsPerUnit, scroll.scrollHeight - scroll.clientHeight)));
              setScrollLeft(cm, Math.max(0, Math.min(scroll.scrollLeft + dx * wheelPixelsPerUnit, scroll.scrollWidth - scroll.clientWidth)));
              e_preventDefault(e);
              display.wheelStartX = null; // Abort measurement, if in progress
              return;
          }
  
          // 'Project' the visible viewport to cover the area that is being
          // scrolled into view (if we know enough to estimate it).
          if (dy && wheelPixelsPerUnit != null) {
              var pixels = dy * wheelPixelsPerUnit;
              var top = cm.doc.scrollTop, bot = top + display.wrapper.clientHeight;
              if (pixels < 0) top = Math.max(0, top + pixels - 50);
              else bot = Math.min(cm.doc.height, bot + pixels + 50);
              updateDisplaySimple(cm, {top: top, bottom: bot});
          }
  
          if (wheelSamples < 20) {
              if (display.wheelStartX == null) {
                  display.wheelStartX = scroll.scrollLeft;
                  display.wheelStartY = scroll.scrollTop;
                  display.wheelDX = dx;
                  display.wheelDY = dy;
                  setTimeout(function () {
                      if (display.wheelStartX == null) return;
                      var movedX = scroll.scrollLeft - display.wheelStartX;
                      var movedY = scroll.scrollTop - display.wheelStartY;
                      var sample = (movedY && display.wheelDY && movedY / display.wheelDY) ||
                          (movedX && display.wheelDX && movedX / display.wheelDX);
                      display.wheelStartX = display.wheelStartY = null;
                      if (!sample) return;
                      wheelPixelsPerUnit = (wheelPixelsPerUnit * wheelSamples + sample) / (wheelSamples + 1);
                      ++wheelSamples;
                  }, 200);
              } else {
                  display.wheelDX += dx;
                  display.wheelDY += dy;
              }
          }
      }
  
      // KEY EVENTS
  
      // Run a handler that was bound to a key.
      function doHandleBinding(cm, bound, dropShift) {
          if (typeof bound == "string") {
              bound = commands[bound];
              if (!bound) return false;
          }
          // Ensure previous input has been read, so that the handler sees a
          // consistent view of the document
          cm.display.input.ensurePolled();
          var prevShift = cm.display.shift, done = false;
          try {
              if (isReadOnly(cm)) cm.state.suppressEdits = true;
              if (dropShift) cm.display.shift = false;
              done = bound(cm) != Pass;
          } finally {
              cm.display.shift = prevShift;
              cm.state.suppressEdits = false;
          }
          return done;
      }
  
      function lookupKeyForEditor(cm, name, handle) {
          for (var i = 0; i < cm.state.keyMaps.length; i++) {
              var result = lookupKey(name, cm.state.keyMaps[i], handle, cm);
              if (result) return result;
          }
          return (cm.options.extraKeys && lookupKey(name, cm.options.extraKeys, handle, cm))
              || lookupKey(name, cm.options.keyMap, handle, cm);
      }
  
      var stopSeq = new Delayed;
  
      function dispatchKey(cm, name, e, handle) {
          var seq = cm.state.keySeq;
          if (seq) {
              if (isModifierKey(name)) return "handled";
              stopSeq.set(50, function () {
                  if (cm.state.keySeq == seq) {
                      cm.state.keySeq = null;
                      cm.display.input.reset();
                  }
              });
              name = seq + " " + name;
          }
          var result = lookupKeyForEditor(cm, name, handle);
  
          if (result == "multi")
              cm.state.keySeq = name;
          if (result == "handled")
              signalLater(cm, "keyHandled", cm, name, e);
  
          if (result == "handled" || result == "multi") {
              e_preventDefault(e);
              restartBlink(cm);
          }
  
          if (seq && !result && /\'$/.test(name)) {
              e_preventDefault(e);
              return true;
          }
          return !!result;
      }
  
      // Handle a key from the keydown event.
      function handleKeyBinding(cm, e) {
          var name = keyName(e, true);
          if (!name) return false;
  
          if (e.shiftKey && !cm.state.keySeq) {
              // First try to resolve full name (including 'Shift-'). Failing
              // that, see if there is a cursor-motion command (starting with
              // 'go') bound to the keyname without 'Shift-'.
              return dispatchKey(cm, "Shift-" + name, e, function (b) {
                      return doHandleBinding(cm, b, true);
                  })
                  || dispatchKey(cm, name, e, function (b) {
                      if (typeof b == "string" ? /^go[A-Z]/.test(b) : b.motion)
                          return doHandleBinding(cm, b);
                  });
          } else {
              return dispatchKey(cm, name, e, function (b) {
                  return doHandleBinding(cm, b);
              });
          }
      }
  
      // Handle a key from the keypress event
      function handleCharBinding(cm, e, ch) {
          return dispatchKey(cm, "'" + ch + "'", e,
              function (b) {
                  return doHandleBinding(cm, b, true);
              });
      }
  
      var lastStoppedKey = null;
  
      function onKeyDown(e) {
          var cm = this;
          ensureFocus(cm);
          if (signalDOMEvent(cm, e)) return;
          // IE does strange things with escape.
          if (ie && ie_version < 11 && e.keyCode == 27) e.returnValue = false;
          var code = e.keyCode;
          cm.display.shift = code == 16 || e.shiftKey;
          var handled = handleKeyBinding(cm, e);
          if (presto) {
              lastStoppedKey = handled ? code : null;
              // Opera has no cut event... we try to at least catch the key combo
              if (!handled && code == 88 && !hasCopyEvent && (mac ? e.metaKey : e.ctrlKey))
                  cm.replaceSelection("", null, "cut");
          }
  
          // Turn mouse into crosshair when Alt is held on Mac.
          if (code == 18 && !/\bCodeMirror-crosshair\b/.test(cm.display.lineDiv.className))
              showCrossHair(cm);
      }
  
      function showCrossHair(cm) {
          var lineDiv = cm.display.lineDiv;
          addClass(lineDiv, "CodeMirror-crosshair");
  
          function up(e) {
              if (e.keyCode == 18 || !e.altKey) {
                  rmClass(lineDiv, "CodeMirror-crosshair");
                  off(document, "keyup", up);
                  off(document, "mouseover", up);
              }
          }
  
          on(document, "keyup", up);
          on(document, "mouseover", up);
      }
  
      function onKeyUp(e) {
          if (e.keyCode == 16) this.doc.sel.shift = false;
          signalDOMEvent(this, e);
      }
  
      function onKeyPress(e) {
          var cm = this;
          if (eventInWidget(cm.display, e) || signalDOMEvent(cm, e) || e.ctrlKey && !e.altKey || mac && e.metaKey) return;
          var keyCode = e.keyCode, charCode = e.charCode;
          if (presto && keyCode == lastStoppedKey) {
              lastStoppedKey = null;
              e_preventDefault(e);
              return;
          }
          if ((presto && (!e.which || e.which < 10)) && handleKeyBinding(cm, e)) return;
          var ch = String.fromCharCode(charCode == null ? keyCode : charCode);
          if (handleCharBinding(cm, e, ch)) return;
          cm.display.input.onKeyPress(e);
      }
  
      // FOCUS/BLUR EVENTS
  
      function onFocus(cm) {
          if (cm.options.readOnly == "nocursor") return;
          if (!cm.state.focused) {
              signal(cm, "focus", cm);
              cm.state.focused = true;
              addClass(cm.display.wrapper, "CodeMirror-focused");
              // This test prevents this from firing when a context
              // menu is closed (since the input reset would kill the
              // select-all detection hack)
              if (!cm.curOp && cm.display.selForContextMenu != cm.doc.sel) {
                  cm.display.input.reset();
                  if (webkit) setTimeout(function () {
                      cm.display.input.reset(true);
                  }, 20); // Issue #1730
              }
              cm.display.input.receivedFocus();
          }
          restartBlink(cm);
      }
  
      function onBlur(cm) {
          if (cm.state.focused) {
              signal(cm, "blur", cm);
              cm.state.focused = false;
              rmClass(cm.display.wrapper, "CodeMirror-focused");
          }
          clearInterval(cm.display.blinker);
          setTimeout(function () {
              if (!cm.state.focused) cm.display.shift = false;
          }, 150);
      }
  
      // CONTEXT MENU HANDLING
  
      // To make the context menu work, we need to briefly unhide the
      // textarea (making it as unobtrusive as possible) to let the
      // right-click take effect on it.
      function onContextMenu(cm, e) {
          if (eventInWidget(cm.display, e) || contextMenuInGutter(cm, e)) return;
          cm.display.input.onContextMenu(e);
      }
  
      function contextMenuInGutter(cm, e) {
          if (!hasHandler(cm, "gutterContextMenu")) return false;
          return gutterEvent(cm, e, "gutterContextMenu", false, signal);
      }
  
      // UPDATING
  
      // Compute the position of the end of a change (its 'to' property
      // refers to the pre-change end).
      var changeEnd = CodeMirror.changeEnd = function (change) {
          if (!change.text) return change.to;
          return Pos(change.from.line + change.text.length - 1,
              lst(change.text).length + (change.text.length == 1 ? change.from.ch : 0));
      };
  
      // Adjust a position to refer to the post-change position of the
      // same text, or the end of the change if the change covers it.
      function adjustForChange(pos, change) {
          if (cmp(pos, change.from) < 0) return pos;
          if (cmp(pos, change.to) <= 0) return changeEnd(change);
  
          var line = pos.line + change.text.length - (change.to.line - change.from.line) - 1, ch = pos.ch;
          if (pos.line == change.to.line) ch += changeEnd(change).ch - change.to.ch;
          return Pos(line, ch);
      }
  
      function computeSelAfterChange(doc, change) {
          var out = [];
          for (var i = 0; i < doc.sel.ranges.length; i++) {
              var range = doc.sel.ranges[i];
              out.push(new Range(adjustForChange(range.anchor, change),
                  adjustForChange(range.head, change)));
          }
          return normalizeSelection(out, doc.sel.primIndex);
      }
  
      function offsetPos(pos, old, nw) {
          if (pos.line == old.line)
              return Pos(nw.line, pos.ch - old.ch + nw.ch);
          else
              return Pos(nw.line + (pos.line - old.line), pos.ch);
      }
  
      // Used by replaceSelections to allow moving the selection to the
      // start or around the replaced test. Hint may be "start" or "around".
      function computeReplacedSel(doc, changes, hint) {
          var out = [];
          var oldPrev = Pos(doc.first, 0), newPrev = oldPrev;
          for (var i = 0; i < changes.length; i++) {
              var change = changes[i];
              var from = offsetPos(change.from, oldPrev, newPrev);
              var to = offsetPos(changeEnd(change), oldPrev, newPrev);
              oldPrev = change.to;
              newPrev = to;
              if (hint == "around") {
                  var range = doc.sel.ranges[i], inv = cmp(range.head, range.anchor) < 0;
                  out[i] = new Range(inv ? to : from, inv ? from : to);
              } else {
                  out[i] = new Range(from, from);
              }
          }
          return new Selection(out, doc.sel.primIndex);
      }
  
      // Allow "beforeChange" event handlers to influence a change
      function filterChange(doc, change, update) {
          var obj = {
              canceled: false,
              from: change.from,
              to: change.to,
              text: change.text,
              origin: change.origin,
              cancel: function () {
                  this.canceled = true;
              }
          };
          if (update) obj.update = function (from, to, text, origin) {
              if (from) this.from = clipPos(doc, from);
              if (to) this.to = clipPos(doc, to);
              if (text) this.text = text;
              if (origin !== undefined) this.origin = origin;
          };
          signal(doc, "beforeChange", doc, obj);
          if (doc.cm) signal(doc.cm, "beforeChange", doc.cm, obj);
  
          if (obj.canceled) return null;
          return {from: obj.from, to: obj.to, text: obj.text, origin: obj.origin};
      }
  
      // Apply a change to a document, and add it to the document's
      // history, and propagating it to all linked documents.
      function makeChange(doc, change, ignoreReadOnly) {
          if (doc.cm) {
              if (!doc.cm.curOp) return operation(doc.cm, makeChange)(doc, change, ignoreReadOnly);
              if (doc.cm.state.suppressEdits) return;
          }
  
          if (hasHandler(doc, "beforeChange") || doc.cm && hasHandler(doc.cm, "beforeChange")) {
              change = filterChange(doc, change, true);
              if (!change) return;
          }
  
          // Possibly split or suppress the update based on the presence
          // of read-only spans in its range.
          var split = sawReadOnlySpans && !ignoreReadOnly && removeReadOnlyRanges(doc, change.from, change.to);
          if (split) {
              for (var i = split.length - 1; i >= 0; --i)
                  makeChangeInner(doc, {from: split[i].from, to: split[i].to, text: i ? [""] : change.text});
          } else {
              makeChangeInner(doc, change);
          }
      }
  
      function makeChangeInner(doc, change) {
          if (change.text.length == 1 && change.text[0] == "" && cmp(change.from, change.to) == 0) return;
          var selAfter = computeSelAfterChange(doc, change);
          addChangeToHistory(doc, change, selAfter, doc.cm ? doc.cm.curOp.id : NaN);
  
          makeChangeSingleDoc(doc, change, selAfter, stretchSpansOverChange(doc, change));
          var rebased = [];
  
          linkedDocs(doc, function (doc, sharedHist) {
              if (!sharedHist && indexOf(rebased, doc.history) == -1) {
                  rebaseHist(doc.history, change);
                  rebased.push(doc.history);
              }
              makeChangeSingleDoc(doc, change, null, stretchSpansOverChange(doc, change));
          });
      }
  
      // Revert a change stored in a document's history.
      function makeChangeFromHistory(doc, type, allowSelectionOnly) {
          if (doc.cm && doc.cm.state.suppressEdits) return;
  
          var hist = doc.history, event, selAfter = doc.sel;
          var source = type == "undo" ? hist.done : hist.undone, dest = type == "undo" ? hist.undone : hist.done;
  
          // Verify that there is a useable event (so that ctrl-z won't
          // needlessly clear selection events)
          for (var i = 0; i < source.length; i++) {
              event = source[i];
              if (allowSelectionOnly ? event.ranges && !event.equals(doc.sel) : !event.ranges)
                  break;
          }
          if (i == source.length) return;
          hist.lastOrigin = hist.lastSelOrigin = null;
  
          for (; ;) {
              event = source.pop();
              if (event.ranges) {
                  pushSelectionToHistory(event, dest);
                  if (allowSelectionOnly && !event.equals(doc.sel)) {
                      setSelection(doc, event, {clearRedo: false});
                      return;
                  }
                  selAfter = event;
              }
              else break;
          }
  
          // Build up a reverse change object to add to the opposite history
          // stack (redo when undoing, and vice versa).
          var antiChanges = [];
          pushSelectionToHistory(selAfter, dest);
          dest.push({changes: antiChanges, generation: hist.generation});
          hist.generation = event.generation || ++hist.maxGeneration;
  
          var filter = hasHandler(doc, "beforeChange") || doc.cm && hasHandler(doc.cm, "beforeChange");
  
          for (var i = event.changes.length - 1; i >= 0; --i) {
              var change = event.changes[i];
              change.origin = type;
              if (filter && !filterChange(doc, change, false)) {
                  source.length = 0;
                  return;
              }
  
              antiChanges.push(historyChangeFromChange(doc, change));
  
              var after = i ? computeSelAfterChange(doc, change) : lst(source);
              makeChangeSingleDoc(doc, change, after, mergeOldSpans(doc, change));
              if (!i && doc.cm) doc.cm.scrollIntoView({from: change.from, to: changeEnd(change)});
              var rebased = [];
  
              // Propagate to the linked documents
              linkedDocs(doc, function (doc, sharedHist) {
                  if (!sharedHist && indexOf(rebased, doc.history) == -1) {
                      rebaseHist(doc.history, change);
                      rebased.push(doc.history);
                  }
                  makeChangeSingleDoc(doc, change, null, mergeOldSpans(doc, change));
              });
          }
      }
  
      // Sub-views need their line numbers shifted when text is added
      // above or below them in the parent document.
      function shiftDoc(doc, distance) {
          if (distance == 0) return;
          doc.first += distance;
          doc.sel = new Selection(map(doc.sel.ranges, function (range) {
              return new Range(Pos(range.anchor.line + distance, range.anchor.ch),
                  Pos(range.head.line + distance, range.head.ch));
          }), doc.sel.primIndex);
          if (doc.cm) {
              regChange(doc.cm, doc.first, doc.first - distance, distance);
              for (var d = doc.cm.display, l = d.viewFrom; l < d.viewTo; l++)
                  regLineChange(doc.cm, l, "gutter");
          }
      }
  
      // More lower-level change function, handling only a single document
      // (not linked ones).
      function makeChangeSingleDoc(doc, change, selAfter, spans) {
          if (doc.cm && !doc.cm.curOp)
              return operation(doc.cm, makeChangeSingleDoc)(doc, change, selAfter, spans);
  
          if (change.to.line < doc.first) {
              shiftDoc(doc, change.text.length - 1 - (change.to.line - change.from.line));
              return;
          }
          if (change.from.line > doc.lastLine()) return;
  
          // Clip the change to the size of this doc
          if (change.from.line < doc.first) {
              var shift = change.text.length - 1 - (doc.first - change.from.line);
              shiftDoc(doc, shift);
              change = {
                  from: Pos(doc.first, 0), to: Pos(change.to.line + shift, change.to.ch),
                  text: [lst(change.text)], origin: change.origin
              };
          }
          var last = doc.lastLine();
          if (change.to.line > last) {
              change = {
                  from: change.from, to: Pos(last, getLine(doc, last).text.length),
                  text: [change.text[0]], origin: change.origin
              };
          }
  
          change.removed = getBetween(doc, change.from, change.to);
  
          if (!selAfter) selAfter = computeSelAfterChange(doc, change);
          if (doc.cm) makeChangeSingleDocInEditor(doc.cm, change, spans);
          else updateDoc(doc, change, spans);
          setSelectionNoUndo(doc, selAfter, sel_dontScroll);
      }
  
      // Handle the interaction of a change to a document with the editor
      // that this document is part of.
      function makeChangeSingleDocInEditor(cm, change, spans) {
          var doc = cm.doc, display = cm.display, from = change.from, to = change.to;
  
          var recomputeMaxLength = false, checkWidthStart = from.line;
          if (!cm.options.lineWrapping) {
              checkWidthStart = lineNo(visualLine(getLine(doc, from.line)));
              doc.iter(checkWidthStart, to.line + 1, function (line) {
                  if (line == display.maxLine) {
                      recomputeMaxLength = true;
                      return true;
                  }
              });
          }
  
          if (doc.sel.contains(change.from, change.to) > -1)
              signalCursorActivity(cm);
  
          updateDoc(doc, change, spans, estimateHeight(cm));
  
          if (!cm.options.lineWrapping) {
              doc.iter(checkWidthStart, from.line + change.text.length, function (line) {
                  var len = lineLength(line);
                  if (len > display.maxLineLength) {
                      display.maxLine = line;
                      display.maxLineLength = len;
                      display.maxLineChanged = true;
                      recomputeMaxLength = false;
                  }
              });
              if (recomputeMaxLength) cm.curOp.updateMaxLine = true;
          }
  
          // Adjust frontier, schedule worker
          doc.frontier = Math.min(doc.frontier, from.line);
          startWorker(cm, 400);
  
          var lendiff = change.text.length - (to.line - from.line) - 1;
          // Remember that these lines changed, for updating the display
          if (change.full)
              regChange(cm);
          else if (from.line == to.line && change.text.length == 1 && !isWholeLineUpdate(cm.doc, change))
              regLineChange(cm, from.line, "text");
          else
              regChange(cm, from.line, to.line + 1, lendiff);
  
          var changesHandler = hasHandler(cm, "changes"), changeHandler = hasHandler(cm, "change");
          if (changeHandler || changesHandler) {
              var obj = {
                  from: from, to: to,
                  text: change.text,
                  removed: change.removed,
                  origin: change.origin
              };
              if (changeHandler) signalLater(cm, "change", cm, obj);
              if (changesHandler) (cm.curOp.changeObjs || (cm.curOp.changeObjs = [])).push(obj);
          }
          cm.display.selForContextMenu = null;
      }
  
      function replaceRange(doc, code, from, to, origin) {
          if (!to) to = from;
          if (cmp(to, from) < 0) {
              var tmp = to;
              to = from;
              from = tmp;
          }
          if (typeof code == "string") code = splitLines(code);
          makeChange(doc, {from: from, to: to, text: code, origin: origin});
      }
  
      // SCROLLING THINGS INTO VIEW
  
      // If an editor sits on the top or bottom of the window, partially
      // scrolled out of view, this ensures that the cursor is visible.
      function maybeScrollWindow(cm, coords) {
          if (signalDOMEvent(cm, "scrollCursorIntoView")) return;
  
          var display = cm.display, box = display.sizer.getBoundingClientRect(), doScroll = null;
          if (coords.top + box.top < 0) doScroll = true;
          else if (coords.bottom + box.top > (window.innerHeight || document.documentElement.clientHeight)) doScroll = false;
          if (doScroll != null && !phantom) {
              var scrollNode = elt("div", "\u200b", null, "position: absolute; top: " +
                  (coords.top - display.viewOffset - paddingTop(cm.display)) + "px; height: " +
                  (coords.bottom - coords.top + scrollGap(cm) + display.barHeight) + "px; left: " +
                  coords.left + "px; width: 2px;");
              cm.display.lineSpace.appendChild(scrollNode);
              scrollNode.scrollIntoView(doScroll);
              cm.display.lineSpace.removeChild(scrollNode);
          }
      }
  
      // Scroll a given position into view (immediately), verifying that
      // it actually became visible (as line heights are accurately
      // measured, the position of something may 'drift' during drawing).
      function scrollPosIntoView(cm, pos, end, margin) {
          if (margin == null) margin = 0;
          for (var limit = 0; limit < 5; limit++) {
              var changed = false, coords = cursorCoords(cm, pos);
              var endCoords = !end || end == pos ? coords : cursorCoords(cm, end);
              var scrollPos = calculateScrollPos(cm, Math.min(coords.left, endCoords.left),
                  Math.min(coords.top, endCoords.top) - margin,
                  Math.max(coords.left, endCoords.left),
                  Math.max(coords.bottom, endCoords.bottom) + margin);
              var startTop = cm.doc.scrollTop, startLeft = cm.doc.scrollLeft;
              if (scrollPos.scrollTop != null) {
                  setScrollTop(cm, scrollPos.scrollTop);
                  if (Math.abs(cm.doc.scrollTop - startTop) > 1) changed = true;
              }
              if (scrollPos.scrollLeft != null) {
                  setScrollLeft(cm, scrollPos.scrollLeft);
                  if (Math.abs(cm.doc.scrollLeft - startLeft) > 1) changed = true;
              }
              if (!changed) break;
          }
          return coords;
      }
  
      // Scroll a given set of coordinates into view (immediately).
      function scrollIntoView(cm, x1, y1, x2, y2) {
          var scrollPos = calculateScrollPos(cm, x1, y1, x2, y2);
          if (scrollPos.scrollTop != null) setScrollTop(cm, scrollPos.scrollTop);
          if (scrollPos.scrollLeft != null) setScrollLeft(cm, scrollPos.scrollLeft);
      }
  
      // Calculate a new scroll position needed to scroll the given
      // rectangle into view. Returns an object with scrollTop and
      // scrollLeft properties. When these are undefined, the
      // vertical/horizontal position does not need to be adjusted.
      function calculateScrollPos(cm, x1, y1, x2, y2) {
          var display = cm.display, snapMargin = textHeight(cm.display);
          if (y1 < 0) y1 = 0;
          var screentop = cm.curOp && cm.curOp.scrollTop != null ? cm.curOp.scrollTop : display.scroller.scrollTop;
          var screen = displayHeight(cm), result = {};
          if (y2 - y1 > screen) y2 = y1 + screen;
          var docBottom = cm.doc.height + paddingVert(display);
          var atTop = y1 < snapMargin, atBottom = y2 > docBottom - snapMargin;
          if (y1 < screentop) {
              result.scrollTop = atTop ? 0 : y1;
          } else if (y2 > screentop + screen) {
              var newTop = Math.min(y1, (atBottom ? docBottom : y2) - screen);
              if (newTop != screentop) result.scrollTop = newTop;
          }
  
          var screenleft = cm.curOp && cm.curOp.scrollLeft != null ? cm.curOp.scrollLeft : display.scroller.scrollLeft;
          var screenw = displayWidth(cm) - (cm.options.fixedGutter ? display.gutters.offsetWidth : 0);
          var tooWide = x2 - x1 > screenw;
          if (tooWide) x2 = x1 + screenw;
          if (x1 < 10)
              result.scrollLeft = 0;
          else if (x1 < screenleft)
              result.scrollLeft = Math.max(0, x1 - (tooWide ? 0 : 10));
          else if (x2 > screenw + screenleft - 3)
              result.scrollLeft = x2 + (tooWide ? 0 : 10) - screenw;
          return result;
      }
  
      // Store a relative adjustment to the scroll position in the current
      // operation (to be applied when the operation finishes).
      function addToScrollPos(cm, left, top) {
          if (left != null || top != null) resolveScrollToPos(cm);
          if (left != null)
              cm.curOp.scrollLeft = (cm.curOp.scrollLeft == null ? cm.doc.scrollLeft : cm.curOp.scrollLeft) + left;
          if (top != null)
              cm.curOp.scrollTop = (cm.curOp.scrollTop == null ? cm.doc.scrollTop : cm.curOp.scrollTop) + top;
      }
  
      // Make sure that at the end of the operation the current cursor is
      // shown.
      function ensureCursorVisible(cm) {
          resolveScrollToPos(cm);
          var cur = cm.getCursor(), from = cur, to = cur;
          if (!cm.options.lineWrapping) {
              from = cur.ch ? Pos(cur.line, cur.ch - 1) : cur;
              to = Pos(cur.line, cur.ch + 1);
          }
          cm.curOp.scrollToPos = {from: from, to: to, margin: cm.options.cursorScrollMargin, isCursor: true};
      }
  
      // When an operation has its scrollToPos property set, and another
      // scroll action is applied before the end of the operation, this
      // 'simulates' scrolling that position into view in a cheap way, so
      // that the effect of intermediate scroll commands is not ignored.
      function resolveScrollToPos(cm) {
          var range = cm.curOp.scrollToPos;
          if (range) {
              cm.curOp.scrollToPos = null;
              var from = estimateCoords(cm, range.from), to = estimateCoords(cm, range.to);
              var sPos = calculateScrollPos(cm, Math.min(from.left, to.left),
                  Math.min(from.top, to.top) - range.margin,
                  Math.max(from.right, to.right),
                  Math.max(from.bottom, to.bottom) + range.margin);
              cm.scrollTo(sPos.scrollLeft, sPos.scrollTop);
          }
      }
  
      // API UTILITIES
  
      // Indent the given line. The how parameter can be "smart",
      // "add"/null, "subtract", or "prev". When aggressive is false
      // (typically set to true for forced single-line indents), empty
      // lines are not indented, and places where the mode returns Pass
      // are left alone.
      function indentLine(cm, n, how, aggressive) {
          var doc = cm.doc, state;
          if (how == null) how = "add";
          if (how == "smart") {
              // Fall back to "prev" when the mode doesn't have an indentation
              // method.
              if (!doc.mode.indent) how = "prev";
              else state = getStateBefore(cm, n);
          }
  
          var tabSize = cm.options.tabSize;
          var line = getLine(doc, n), curSpace = countColumn(line.text, null, tabSize);
          if (line.stateAfter) line.stateAfter = null;
          var curSpaceString = line.text.match(/^\s*/)[0], indentation;
          if (!aggressive && !/\S/.test(line.text)) {
              indentation = 0;
              how = "not";
          } else if (how == "smart") {
              indentation = doc.mode.indent(state, line.text.slice(curSpaceString.length), line.text);
              if (indentation == Pass || indentation > 150) {
                  if (!aggressive) return;
                  how = "prev";
              }
          }
          if (how == "prev") {
              if (n > doc.first) indentation = countColumn(getLine(doc, n - 1).text, null, tabSize);
              else indentation = 0;
          } else if (how == "add") {
              indentation = curSpace + cm.options.indentUnit;
          } else if (how == "subtract") {
              indentation = curSpace - cm.options.indentUnit;
          } else if (typeof how == "number") {
              indentation = curSpace + how;
          }
          indentation = Math.max(0, indentation);
  
          var indentString = "", pos = 0;
          if (cm.options.indentWithTabs)
              for (var i = Math.floor(indentation / tabSize); i; --i) {
                  pos += tabSize;
                  indentString += "\t";
              }
          if (pos < indentation) indentString += spaceStr(indentation - pos);
  
          if (indentString != curSpaceString) {
              replaceRange(doc, indentString, Pos(n, 0), Pos(n, curSpaceString.length), "+input");
          } else {
              // Ensure that, if the cursor was in the whitespace at the start
              // of the line, it is moved to the end of that space.
              for (var i = 0; i < doc.sel.ranges.length; i++) {
                  var range = doc.sel.ranges[i];
                  if (range.head.line == n && range.head.ch < curSpaceString.length) {
                      var pos = Pos(n, curSpaceString.length);
                      replaceOneSelection(doc, i, new Range(pos, pos));
                      break;
                  }
              }
          }
          line.stateAfter = null;
      }
  
      // Utility for applying a change to a line by handle or number,
      // returning the number and optionally registering the line as
      // changed.
      function changeLine(doc, handle, changeType, op) {
          var no = handle, line = handle;
          if (typeof handle == "number") line = getLine(doc, clipLine(doc, handle));
          else no = lineNo(handle);
          if (no == null) return null;
          if (op(line, no) && doc.cm) regLineChange(doc.cm, no, changeType);
          return line;
      }
  
      // Helper for deleting text near the selection(s), used to implement
      // backspace, delete, and similar functionality.
      function deleteNearSelection(cm, compute) {
          var ranges = cm.doc.sel.ranges, kill = [];
          // Build up a set of ranges to kill first, merging overlapping
          // ranges.
          for (var i = 0; i < ranges.length; i++) {
              var toKill = compute(ranges[i]);
              while (kill.length && cmp(toKill.from, lst(kill).to) <= 0) {
                  var replaced = kill.pop();
                  if (cmp(replaced.from, toKill.from) < 0) {
                      toKill.from = replaced.from;
                      break;
                  }
              }
              kill.push(toKill);
          }
          // Next, remove those actual ranges.
          runInOp(cm, function () {
              for (var i = kill.length - 1; i >= 0; i--)
                  replaceRange(cm.doc, "", kill[i].from, kill[i].to, "+delete");
              ensureCursorVisible(cm);
          });
      }
  
      // Used for horizontal relative motion. Dir is -1 or 1 (left or
      // right), unit can be "char", "column" (like char, but doesn't
      // cross line boundaries), "word" (across next word), or "group" (to
      // the start of next group of word or non-word-non-whitespace
      // chars). The visually param controls whether, in right-to-left
      // text, direction 1 means to move towards the next index in the
      // string, or towards the character to the right of the current
      // position. The resulting position will have a hitSide=true
      // property if it reached the end of the document.
      function findPosH(doc, pos, dir, unit, visually) {
          var line = pos.line, ch = pos.ch, origDir = dir;
          var lineObj = getLine(doc, line);
          var possible = true;
  
          function findNextLine() {
              var l = line + dir;
              if (l < doc.first || l >= doc.first + doc.size) return (possible = false);
              line = l;
              return lineObj = getLine(doc, l);
          }
  
          function moveOnce(boundToLine) {
              var next = (visually ? moveVisually : moveLogically)(lineObj, ch, dir, true);
              if (next == null) {
                  if (!boundToLine && findNextLine()) {
                      if (visually) ch = (dir < 0 ? lineRight : lineLeft)(lineObj);
                      else ch = dir < 0 ? lineObj.text.length : 0;
                  } else return (possible = false);
              } else ch = next;
              return true;
          }
  
          if (unit == "char") moveOnce();
          else if (unit == "column") moveOnce(true);
          else if (unit == "word" || unit == "group") {
              var sawType = null, group = unit == "group";
              var helper = doc.cm && doc.cm.getHelper(pos, "wordChars");
              for (var first = true; ; first = false) {
                  if (dir < 0 && !moveOnce(!first)) break;
                  var cur = lineObj.text.charAt(ch) || "\n";
                  var type = isWordChar(cur, helper) ? "w"
                      : group && cur == "\n" ? "n"
                          : !group || /\s/.test(cur) ? null
                              : "p";
                  if (group && !first && !type) type = "s";
                  if (sawType && sawType != type) {
                      if (dir < 0) {
                          dir = 1;
                          moveOnce();
                      }
                      break;
                  }
  
                  if (type) sawType = type;
                  if (dir > 0 && !moveOnce(!first)) break;
              }
          }
          var result = skipAtomic(doc, Pos(line, ch), origDir, true);
          if (!possible) result.hitSide = true;
          return result;
      }
  
      // For relative vertical movement. Dir may be -1 or 1. Unit can be
      // "page" or "line". The resulting position will have a hitSide=true
      // property if it reached the end of the document.
      function findPosV(cm, pos, dir, unit) {
          var doc = cm.doc, x = pos.left, y;
          if (unit == "page") {
              var pageSize = Math.min(cm.display.wrapper.clientHeight, window.innerHeight || document.documentElement.clientHeight);
              y = pos.top + dir * (pageSize - (dir < 0 ? 1.5 : .5) * textHeight(cm.display));
          } else if (unit == "line") {
              y = dir > 0 ? pos.bottom + 3 : pos.top - 3;
          }
          for (; ;) {
              var target = coordsChar(cm, x, y);
              if (!target.outside) break;
              if (dir < 0 ? y <= 0 : y >= doc.height) {
                  target.hitSide = true;
                  break;
              }
              y += dir * 5;
          }
          return target;
      }
  
      // EDITOR METHODS
  
      // The publicly visible API. Note that methodOp(f) means
      // 'wrap f in an operation, performed on its `this` parameter'.
  
      // This is not the complete set of editor methods. Most of the
      // methods defined on the Doc type are also injected into
      // CodeMirror.prototype, for backwards compatibility and
      // convenience.
  
      CodeMirror.prototype = {
          constructor: CodeMirror,
          focus: function () {
              window.focus();
              this.display.input.focus();
          },
  
          setOption: function (option, value) {
              var options = this.options, old = options[option];
              if (options[option] == value && option != "mode") return;
              options[option] = value;
              if (optionHandlers.hasOwnProperty(option))
                  operation(this, optionHandlers[option])(this, value, old);
          },
  
          getOption: function (option) {
              return this.options[option];
          },
          getDoc: function () {
              return this.doc;
          },
  
          addKeyMap: function (map, bottom) {
              this.state.keyMaps[bottom ? "push" : "unshift"](getKeyMap(map));
          },
          removeKeyMap: function (map) {
              var maps = this.state.keyMaps;
              for (var i = 0; i < maps.length; ++i)
                  if (maps[i] == map || maps[i].name == map) {
                      maps.splice(i, 1);
                      return true;
                  }
          },
  
          addOverlay: methodOp(function (spec, options) {
              var mode = spec.token ? spec : CodeMirror.getMode(this.options, spec);
              if (mode.startState) throw new Error("Overlays may not be stateful.");
              this.state.overlays.push({mode: mode, modeSpec: spec, opaque: options && options.opaque});
              this.state.modeGen++;
              regChange(this);
          }),
          removeOverlay: methodOp(function (spec) {
              var overlays = this.state.overlays;
              for (var i = 0; i < overlays.length; ++i) {
                  var cur = overlays[i].modeSpec;
                  if (cur == spec || typeof spec == "string" && cur.name == spec) {
                      overlays.splice(i, 1);
                      this.state.modeGen++;
                      regChange(this);
                      return;
                  }
              }
          }),
  
          indentLine: methodOp(function (n, dir, aggressive) {
              if (typeof dir != "string" && typeof dir != "number") {
                  if (dir == null) dir = this.options.smartIndent ? "smart" : "prev";
                  else dir = dir ? "add" : "subtract";
              }
              if (isLine(this.doc, n)) indentLine(this, n, dir, aggressive);
          }),
          indentSelection: methodOp(function (how) {
              var ranges = this.doc.sel.ranges, end = -1;
              for (var i = 0; i < ranges.length; i++) {
                  var range = ranges[i];
                  if (!range.empty()) {
                      var from = range.from(), to = range.to();
                      var start = Math.max(end, from.line);
                      end = Math.min(this.lastLine(), to.line - (to.ch ? 0 : 1)) + 1;
                      for (var j = start; j < end; ++j)
                          indentLine(this, j, how);
                      var newRanges = this.doc.sel.ranges;
                      if (from.ch == 0 && ranges.length == newRanges.length && newRanges[i].from().ch > 0)
                          replaceOneSelection(this.doc, i, new Range(from, newRanges[i].to()), sel_dontScroll);
                  } else if (range.head.line > end) {
                      indentLine(this, range.head.line, how, true);
                      end = range.head.line;
                      if (i == this.doc.sel.primIndex) ensureCursorVisible(this);
                  }
              }
          }),
  
          // Fetch the parser token for a given character. Useful for hacks
          // that want to inspect the mode state (say, for completion).
          getTokenAt: function (pos, precise) {
              return takeToken(this, pos, precise);
          },
  
          getLineTokens: function (line, precise) {
              return takeToken(this, Pos(line), precise, true);
          },
  
          getTokenTypeAt: function (pos) {
              pos = clipPos(this.doc, pos);
              var styles = getLineStyles(this, getLine(this.doc, pos.line));
              var before = 0, after = (styles.length - 1) / 2, ch = pos.ch;
              var type;
              if (ch == 0) type = styles[2];
              else for (; ;) {
                  var mid = (before + after) >> 1;
                  if ((mid ? styles[mid * 2 - 1] : 0) >= ch) after = mid;
                  else if (styles[mid * 2 + 1] < ch) before = mid + 1;
                  else {
                      type = styles[mid * 2 + 2];
                      break;
                  }
              }
              var cut = type ? type.indexOf("cm-overlay ") : -1;
              return cut < 0 ? type : cut == 0 ? null : type.slice(0, cut - 1);
          },
  
          getModeAt: function (pos) {
              var mode = this.doc.mode;
              if (!mode.innerMode) return mode;
              return CodeMirror.innerMode(mode, this.getTokenAt(pos).state).mode;
          },
  
          getHelper: function (pos, type) {
              return this.getHelpers(pos, type)[0];
          },
  
          getHelpers: function (pos, type) {
              var found = [];
              if (!helpers.hasOwnProperty(type)) return helpers;
              var help = helpers[type], mode = this.getModeAt(pos);
              if (typeof mode[type] == "string") {
                  if (help[mode[type]]) found.push(help[mode[type]]);
              } else if (mode[type]) {
                  for (var i = 0; i < mode[type].length; i++) {
                      var val = help[mode[type][i]];
                      if (val) found.push(val);
                  }
              } else if (mode.helperType && help[mode.helperType]) {
                  found.push(help[mode.helperType]);
              } else if (help[mode.name]) {
                  found.push(help[mode.name]);
              }
              for (var i = 0; i < help._global.length; i++) {
                  var cur = help._global[i];
                  if (cur.pred(mode, this) && indexOf(found, cur.val) == -1)
                      found.push(cur.val);
              }
              return found;
          },
  
          getStateAfter: function (line, precise) {
              var doc = this.doc;
              line = clipLine(doc, line == null ? doc.first + doc.size - 1 : line);
              return getStateBefore(this, line + 1, precise);
          },
  
          cursorCoords: function (start, mode) {
              var pos, range = this.doc.sel.primary();
              if (start == null) pos = range.head;
              else if (typeof start == "object") pos = clipPos(this.doc, start);
              else pos = start ? range.from() : range.to();
              return cursorCoords(this, pos, mode || "page");
          },
  
          charCoords: function (pos, mode) {
              return charCoords(this, clipPos(this.doc, pos), mode || "page");
          },
  
          coordsChar: function (coords, mode) {
              coords = fromCoordSystem(this, coords, mode || "page");
              return coordsChar(this, coords.left, coords.top);
          },
  
          lineAtHeight: function (height, mode) {
              height = fromCoordSystem(this, {top: height, left: 0}, mode || "page").top;
              return lineAtHeight(this.doc, height + this.display.viewOffset);
          },
          heightAtLine: function (line, mode) {
              var end = false, last = this.doc.first + this.doc.size - 1;
              if (line < this.doc.first) line = this.doc.first;
              else if (line > last) {
                  line = last;
                  end = true;
              }
              var lineObj = getLine(this.doc, line);
              return intoCoordSystem(this, lineObj, {top: 0, left: 0}, mode || "page").top +
                  (end ? this.doc.height - heightAtLine(lineObj) : 0);
          },
  
          defaultTextHeight: function () {
              return textHeight(this.display);
          },
          defaultCharWidth: function () {
              return charWidth(this.display);
          },
  
          setGutterMarker: methodOp(function (line, gutterID, value) {
              return changeLine(this.doc, line, "gutter", function (line) {
                  var markers = line.gutterMarkers || (line.gutterMarkers = {});
                  markers[gutterID] = value;
                  if (!value && isEmpty(markers)) line.gutterMarkers = null;
                  return true;
              });
          }),
  
          clearGutter: methodOp(function (gutterID) {
              var cm = this, doc = cm.doc, i = doc.first;
              doc.iter(function (line) {
                  if (line.gutterMarkers && line.gutterMarkers[gutterID]) {
                      line.gutterMarkers[gutterID] = null;
                      regLineChange(cm, i, "gutter");
                      if (isEmpty(line.gutterMarkers)) line.gutterMarkers = null;
                  }
                  ++i;
              });
          }),
  
          addLineWidget: methodOp(function (handle, node, options) {
              return addLineWidget(this, handle, node, options);
          }),
  
          removeLineWidget: function (widget) {
              widget.clear();
          },
  
          lineInfo: function (line) {
              if (typeof line == "number") {
                  if (!isLine(this.doc, line)) return null;
                  var n = line;
                  line = getLine(this.doc, line);
                  if (!line) return null;
              } else {
                  var n = lineNo(line);
                  if (n == null) return null;
              }
              return {
                  line: n, handle: line, text: line.text, gutterMarkers: line.gutterMarkers,
                  textClass: line.textClass, bgClass: line.bgClass, wrapClass: line.wrapClass,
                  widgets: line.widgets
              };
          },
  
          getViewport: function () {
              return {from: this.display.viewFrom, to: this.display.viewTo};
          },
  
          addWidget: function (pos, node, scroll, vert, horiz) {
              var display = this.display;
              pos = cursorCoords(this, clipPos(this.doc, pos));
              var top = pos.bottom, left = pos.left;
              node.style.position = "absolute";
              node.setAttribute("cm-ignore-events", "true");
              this.display.input.setUneditable(node);
              display.sizer.appendChild(node);
              if (vert == "over") {
                  top = pos.top;
              } else if (vert == "above" || vert == "near") {
                  var vspace = Math.max(display.wrapper.clientHeight, this.doc.height),
                      hspace = Math.max(display.sizer.clientWidth, display.lineSpace.clientWidth);
                  // Default to positioning above (if specified and possible); otherwise default to positioning below
                  if ((vert == 'above' || pos.bottom + node.offsetHeight > vspace) && pos.top > node.offsetHeight)
                      top = pos.top - node.offsetHeight;
                  else if (pos.bottom + node.offsetHeight <= vspace)
                      top = pos.bottom;
                  if (left + node.offsetWidth > hspace)
                      left = hspace - node.offsetWidth;
              }
              node.style.top = top + "px";
              node.style.left = node.style.right = "";
              if (horiz == "right") {
                  left = display.sizer.clientWidth - node.offsetWidth;
                  node.style.right = "0px";
              } else {
                  if (horiz == "left") left = 0;
                  else if (horiz == "middle") left = (display.sizer.clientWidth - node.offsetWidth) / 2;
                  node.style.left = left + "px";
              }
              if (scroll)
                  scrollIntoView(this, left, top, left + node.offsetWidth, top + node.offsetHeight);
          },
  
          triggerOnKeyDown: methodOp(onKeyDown),
          triggerOnKeyPress: methodOp(onKeyPress),
          triggerOnKeyUp: onKeyUp,
  
          execCommand: function (cmd) {
              if (commands.hasOwnProperty(cmd))
                  return commands[cmd](this);
          },
  
          findPosH: function (from, amount, unit, visually) {
              var dir = 1;
              if (amount < 0) {
                  dir = -1;
                  amount = -amount;
              }
              for (var i = 0, cur = clipPos(this.doc, from); i < amount; ++i) {
                  cur = findPosH(this.doc, cur, dir, unit, visually);
                  if (cur.hitSide) break;
              }
              return cur;
          },
  
          moveH: methodOp(function (dir, unit) {
              var cm = this;
              cm.extendSelectionsBy(function (range) {
                  if (cm.display.shift || cm.doc.extend || range.empty())
                      return findPosH(cm.doc, range.head, dir, unit, cm.options.rtlMoveVisually);
                  else
                      return dir < 0 ? range.from() : range.to();
              }, sel_move);
          }),
  
          deleteH: methodOp(function (dir, unit) {
              var sel = this.doc.sel, doc = this.doc;
              if (sel.somethingSelected())
                  doc.replaceSelection("", null, "+delete");
              else
                  deleteNearSelection(this, function (range) {
                      var other = findPosH(doc, range.head, dir, unit, false);
                      return dir < 0 ? {from: other, to: range.head} : {from: range.head, to: other};
                  });
          }),
  
          findPosV: function (from, amount, unit, goalColumn) {
              var dir = 1, x = goalColumn;
              if (amount < 0) {
                  dir = -1;
                  amount = -amount;
              }
              for (var i = 0, cur = clipPos(this.doc, from); i < amount; ++i) {
                  var coords = cursorCoords(this, cur, "div");
                  if (x == null) x = coords.left;
                  else coords.left = x;
                  cur = findPosV(this, coords, dir, unit);
                  if (cur.hitSide) break;
              }
              return cur;
          },
  
          moveV: methodOp(function (dir, unit) {
              var cm = this, doc = this.doc, goals = [];
              var collapse = !cm.display.shift && !doc.extend && doc.sel.somethingSelected();
              doc.extendSelectionsBy(function (range) {
                  if (collapse)
                      return dir < 0 ? range.from() : range.to();
                  var headPos = cursorCoords(cm, range.head, "div");
                  if (range.goalColumn != null) headPos.left = range.goalColumn;
                  goals.push(headPos.left);
                  var pos = findPosV(cm, headPos, dir, unit);
                  if (unit == "page" && range == doc.sel.primary())
                      addToScrollPos(cm, null, charCoords(cm, pos, "div").top - headPos.top);
                  return pos;
              }, sel_move);
              if (goals.length) for (var i = 0; i < doc.sel.ranges.length; i++)
                  doc.sel.ranges[i].goalColumn = goals[i];
          }),
  
          // Find the word at the given position (as returned by coordsChar).
          findWordAt: function (pos) {
              var doc = this.doc, line = getLine(doc, pos.line).text;
              var start = pos.ch, end = pos.ch;
              if (line) {
                  var helper = this.getHelper(pos, "wordChars");
                  if ((pos.xRel < 0 || end == line.length) && start) --start; else ++end;
                  var startChar = line.charAt(start);
                  var check = isWordChar(startChar, helper)
                      ? function (ch) {
                          return isWordChar(ch, helper);
                      }
                      : /\s/.test(startChar) ? function (ch) {
                          return /\s/.test(ch);
                      }
                          : function (ch) {
                              return !/\s/.test(ch) && !isWordChar(ch);
                          };
                  while (start > 0 && check(line.charAt(start - 1))) --start;
                  while (end < line.length && check(line.charAt(end))) ++end;
              }
              return new Range(Pos(pos.line, start), Pos(pos.line, end));
          },
  
          toggleOverwrite: function (value) {
              if (value != null && value == this.state.overwrite) return;
              if (this.state.overwrite = !this.state.overwrite)
                  addClass(this.display.cursorDiv, "CodeMirror-overwrite");
              else
                  rmClass(this.display.cursorDiv, "CodeMirror-overwrite");
  
              signal(this, "overwriteToggle", this, this.state.overwrite);
          },
          hasFocus: function () {
              return this.display.input.getField() == activeElt();
          },
  
          scrollTo: methodOp(function (x, y) {
              if (x != null || y != null) resolveScrollToPos(this);
              if (x != null) this.curOp.scrollLeft = x;
              if (y != null) this.curOp.scrollTop = y;
          }),
          getScrollInfo: function () {
              var scroller = this.display.scroller;
              return {
                  left: scroller.scrollLeft, top: scroller.scrollTop,
                  height: scroller.scrollHeight - scrollGap(this) - this.display.barHeight,
                  width: scroller.scrollWidth - scrollGap(this) - this.display.barWidth,
                  clientHeight: displayHeight(this), clientWidth: displayWidth(this)
              };
          },
  
          scrollIntoView: methodOp(function (range, margin) {
              if (range == null) {
                  range = {from: this.doc.sel.primary().head, to: null};
                  if (margin == null) margin = this.options.cursorScrollMargin;
              } else if (typeof range == "number") {
                  range = {from: Pos(range, 0), to: null};
              } else if (range.from == null) {
                  range = {from: range, to: null};
              }
              if (!range.to) range.to = range.from;
              range.margin = margin || 0;
  
              if (range.from.line != null) {
                  resolveScrollToPos(this);
                  this.curOp.scrollToPos = range;
              } else {
                  var sPos = calculateScrollPos(this, Math.min(range.from.left, range.to.left),
                      Math.min(range.from.top, range.to.top) - range.margin,
                      Math.max(range.from.right, range.to.right),
                      Math.max(range.from.bottom, range.to.bottom) + range.margin);
                  this.scrollTo(sPos.scrollLeft, sPos.scrollTop);
              }
          }),
  
          setSize: methodOp(function (width, height) {
              var cm = this;
  
              function interpret(val) {
                  return typeof val == "number" || /^\d+$/.test(String(val)) ? val + "px" : val;
              }
  
              if (width != null) cm.display.wrapper.style.width = interpret(width);
              if (height != null) cm.display.wrapper.style.height = interpret(height);
              if (cm.options.lineWrapping) clearLineMeasurementCache(this);
              var lineNo = cm.display.viewFrom;
              cm.doc.iter(lineNo, cm.display.viewTo, function (line) {
                  if (line.widgets) for (var i = 0; i < line.widgets.length; i++)
                      if (line.widgets[i].noHScroll) {
                          regLineChange(cm, lineNo, "widget");
                          break;
                      }
                  ++lineNo;
              });
              cm.curOp.forceUpdate = true;
              signal(cm, "refresh", this);
          }),
  
          operation: function (f) {
              return runInOp(this, f);
          },
  
          refresh: methodOp(function () {
              var oldHeight = this.display.cachedTextHeight;
              regChange(this);
              this.curOp.forceUpdate = true;
              clearCaches(this);
              this.scrollTo(this.doc.scrollLeft, this.doc.scrollTop);
              updateGutterSpace(this);
              if (oldHeight == null || Math.abs(oldHeight - textHeight(this.display)) > .5)
                  estimateLineHeights(this);
              signal(this, "refresh", this);
          }),
  
          swapDoc: methodOp(function (doc) {
              var old = this.doc;
              old.cm = null;
              attachDoc(this, doc);
              clearCaches(this);
              this.display.input.reset();
              this.scrollTo(doc.scrollLeft, doc.scrollTop);
              this.curOp.forceScroll = true;
              signalLater(this, "swapDoc", this, old);
              return old;
          }),
  
          getInputField: function () {
              return this.display.input.getField();
          },
          getWrapperElement: function () {
              return this.display.wrapper;
          },
          getScrollerElement: function () {
              return this.display.scroller;
          },
          getGutterElement: function () {
              return this.display.gutters;
          }
      };
      eventMixin(CodeMirror);
  
      // OPTION DEFAULTS
  
      // The default configuration options.
      var defaults = CodeMirror.defaults = {};
      // Functions to run when options are changed.
      var optionHandlers = CodeMirror.optionHandlers = {};
  
      function option(name, deflt, handle, notOnInit) {
          CodeMirror.defaults[name] = deflt;
          if (handle) optionHandlers[name] =
              notOnInit ? function (cm, val, old) {
                  if (old != Init) handle(cm, val, old);
              } : handle;
      }
  
      // Passed to option handlers when there is no old value.
      var Init = CodeMirror.Init = {
          toString: function () {
              return "CodeMirror.Init";
          }
      };
  
      // These two are, on init, called from the constructor because they
      // have to be initialized before the editor can start at all.
      option("value", "", function (cm, val) {
          cm.setValue(val);
      }, true);
      option("mode", null, function (cm, val) {
          cm.doc.modeOption = val;
          loadMode(cm);
      }, true);
  
      option("indentUnit", 2, loadMode, true);
      option("indentWithTabs", false);
      option("smartIndent", true);
      option("tabSize", 4, function (cm) {
          resetModeState(cm);
          clearCaches(cm);
          regChange(cm);
      }, true);
      option("specialChars", /[\t\u0000-\u0019\u00ad\u200b-\u200f\u2028\u2029\ufeff]/g, function (cm, val) {
          cm.options.specialChars = new RegExp(val.source + (val.test("\t") ? "" : "|\t"), "g");
          cm.refresh();
      }, true);
      option("specialCharPlaceholder", defaultSpecialCharPlaceholder, function (cm) {
          cm.refresh();
      }, true);
      option("electricChars", true);
      option("inputStyle", mobile ? "contenteditable" : "textarea", function () {
          throw new Error("inputStyle can not (yet) be changed in a running editor"); // FIXME
      }, true);
      option("rtlMoveVisually", !windows);
      option("wholeLineUpdateBefore", true);
  
      option("theme", "default", function (cm) {
          themeChanged(cm);
          guttersChanged(cm);
      }, true);
      option("keyMap", "default", function (cm, val, old) {
          var next = getKeyMap(val);
          var prev = old != CodeMirror.Init && getKeyMap(old);
          if (prev && prev.detach) prev.detach(cm, next);
          if (next.attach) next.attach(cm, prev || null);
      });
      option("extraKeys", null);
  
      option("lineWrapping", false, wrappingChanged, true);
      option("gutters", [], function (cm) {
          setGuttersForLineNumbers(cm.options);
          guttersChanged(cm);
      }, true);
      option("fixedGutter", true, function (cm, val) {
          cm.display.gutters.style.left = val ? compensateForHScroll(cm.display) + "px" : "0";
          cm.refresh();
      }, true);
      option("coverGutterNextToScrollbar", false, function (cm) {
          updateScrollbars(cm);
      }, true);
      option("scrollbarStyle", "native", function (cm) {
          initScrollbars(cm);
          updateScrollbars(cm);
          cm.display.scrollbars.setScrollTop(cm.doc.scrollTop);
          cm.display.scrollbars.setScrollLeft(cm.doc.scrollLeft);
      }, true);
      option("lineNumbers", false, function (cm) {
          setGuttersForLineNumbers(cm.options);
          guttersChanged(cm);
      }, true);
      option("firstLineNumber", 1, guttersChanged, true);
      option("lineNumberFormatter", function (integer) {
          return integer;
      }, guttersChanged, true);
      option("showCursorWhenSelecting", false, updateSelection, true);
  
      option("resetSelectionOnContextMenu", true);
  
      option("readOnly", false, function (cm, val) {
          if (val == "nocursor") {
              onBlur(cm);
              cm.display.input.blur();
              cm.display.disabled = true;
          } else {
              cm.display.disabled = false;
              if (!val) cm.display.input.reset();
          }
      });
      option("disableInput", false, function (cm, val) {
          if (!val) cm.display.input.reset();
      }, true);
      option("dragDrop", true);
  
      option("cursorBlinkRate", 530);
      option("cursorScrollMargin", 0);
      option("cursorHeight", 1, updateSelection, true);
      option("singleCursorHeightPerLine", true, updateSelection, true);
      option("workTime", 100);
      option("workDelay", 100);
      option("flattenSpans", true, resetModeState, true);
      option("addModeClass", false, resetModeState, true);
      option("pollInterval", 100);
      option("undoDepth", 200, function (cm, val) {
          cm.doc.history.undoDepth = val;
      });
      option("historyEventDelay", 1250);
      option("viewportMargin", 10, function (cm) {
          cm.refresh();
      }, true);
      option("maxHighlightLength", 10000, resetModeState, true);
      option("moveInputWithCursor", true, function (cm, val) {
          if (!val) cm.display.input.resetPosition();
      });
  
      option("tabindex", null, function (cm, val) {
          cm.display.input.getField().tabIndex = val || "";
      });
      option("autofocus", null);
  
      // MODE DEFINITION AND QUERYING
  
      // Known modes, by name and by MIME
      var modes = CodeMirror.modes = {}, mimeModes = CodeMirror.mimeModes = {};
  
      // Extra arguments are stored as the mode's dependencies, which is
      // used by (legacy) mechanisms like loadmode.js to automatically
      // load a mode. (Preferred mechanism is the require/define calls.)
      CodeMirror.defineMode = function (name, mode) {
          if (!CodeMirror.defaults.mode && name != "null") CodeMirror.defaults.mode = name;
          if (arguments.length > 2)
              mode.dependencies = Array.prototype.slice.call(arguments, 2);
          modes[name] = mode;
      };
  
      CodeMirror.defineMIME = function (mime, spec) {
          mimeModes[mime] = spec;
      };
  
      // Given a MIME type, a {name, ...options} config object, or a name
      // string, return a mode config object.
      CodeMirror.resolveMode = function (spec) {
          if (typeof spec == "string" && mimeModes.hasOwnProperty(spec)) {
              spec = mimeModes[spec];
          } else if (spec && typeof spec.name == "string" && mimeModes.hasOwnProperty(spec.name)) {
              var found = mimeModes[spec.name];
              if (typeof found == "string") found = {name: found};
              spec = createObj(found, spec);
              spec.name = found.name;
          } else if (typeof spec == "string" && /^[\w\-]+\/[\w\-]+\+xml$/.test(spec)) {
              return CodeMirror.resolveMode("application/xml");
          }
          if (typeof spec == "string") return {name: spec};
          else return spec || {name: "null"};
      };
  
      // Given a mode spec (anything that resolveMode accepts), find and
      // initialize an actual mode object.
      CodeMirror.getMode = function (options, spec) {
          var spec = CodeMirror.resolveMode(spec);
          var mfactory = modes[spec.name];
          if (!mfactory) return CodeMirror.getMode(options, "text/plain");
          var modeObj = mfactory(options, spec);
          if (modeExtensions.hasOwnProperty(spec.name)) {
              var exts = modeExtensions[spec.name];
              for (var prop in exts) {
                  if (!exts.hasOwnProperty(prop)) continue;
                  if (modeObj.hasOwnProperty(prop)) modeObj["_" + prop] = modeObj[prop];
                  modeObj[prop] = exts[prop];
              }
          }
          modeObj.name = spec.name;
          if (spec.helperType) modeObj.helperType = spec.helperType;
          if (spec.modeProps) for (var prop in spec.modeProps)
              modeObj[prop] = spec.modeProps[prop];
  
          return modeObj;
      };
  
      // Minimal default mode.
      CodeMirror.defineMode("null", function () {
          return {
              token: function (stream) {
                  stream.skipToEnd();
              }
          };
      });
      CodeMirror.defineMIME("text/plain", "null");
  
      // This can be used to attach properties to mode objects from
      // outside the actual mode definition.
      var modeExtensions = CodeMirror.modeExtensions = {};
      CodeMirror.extendMode = function (mode, properties) {
          var exts = modeExtensions.hasOwnProperty(mode) ? modeExtensions[mode] : (modeExtensions[mode] = {});
          copyObj(properties, exts);
      };
  
      // EXTENSIONS
  
      CodeMirror.defineExtension = function (name, func) {
          CodeMirror.prototype[name] = func;
      };
      CodeMirror.defineDocExtension = function (name, func) {
          Doc.prototype[name] = func;
      };
      CodeMirror.defineOption = option;
  
      var initHooks = [];
      CodeMirror.defineInitHook = function (f) {
          initHooks.push(f);
      };
  
      var helpers = CodeMirror.helpers = {};
      CodeMirror.registerHelper = function (type, name, value) {
          if (!helpers.hasOwnProperty(type)) helpers[type] = CodeMirror[type] = {_global: []};
          helpers[type][name] = value;
      };
      CodeMirror.registerGlobalHelper = function (type, name, predicate, value) {
          CodeMirror.registerHelper(type, name, value);
          helpers[type]._global.push({pred: predicate, val: value});
      };
  
      // MODE STATE HANDLING
  
      // Utility functions for working with state. Exported because nested
      // modes need to do this for their inner modes.
  
      var copyState = CodeMirror.copyState = function (mode, state) {
          if (state === true) return state;
          if (mode.copyState) return mode.copyState(state);
          var nstate = {};
          for (var n in state) {
              var val = state[n];
              if (val instanceof Array) val = val.concat([]);
              nstate[n] = val;
          }
          return nstate;
      };
  
      var startState = CodeMirror.startState = function (mode, a1, a2) {
          return mode.startState ? mode.startState(a1, a2) : true;
      };
  
      // Given a mode and a state (for that mode), find the inner mode and
      // state at the position that the state refers to.
      CodeMirror.innerMode = function (mode, state) {
          while (mode.innerMode) {
              var info = mode.innerMode(state);
              if (!info || info.mode == mode) break;
              state = info.state;
              mode = info.mode;
          }
          return info || {mode: mode, state: state};
      };
  
      // STANDARD COMMANDS
  
      // Commands are parameter-less actions that can be performed on an
      // editor, mostly used for keybindings.
      var commands = CodeMirror.commands = {
          selectAll: function (cm) {
              cm.setSelection(Pos(cm.firstLine(), 0), Pos(cm.lastLine()), sel_dontScroll);
          },
          singleSelection: function (cm) {
              cm.setSelection(cm.getCursor("anchor"), cm.getCursor("head"), sel_dontScroll);
          },
          killLine: function (cm) {
              deleteNearSelection(cm, function (range) {
                  if (range.empty()) {
                      var len = getLine(cm.doc, range.head.line).text.length;
                      if (range.head.ch == len && range.head.line < cm.lastLine())
                          return {from: range.head, to: Pos(range.head.line + 1, 0)};
                      else
                          return {from: range.head, to: Pos(range.head.line, len)};
                  } else {
                      return {from: range.from(), to: range.to()};
                  }
              });
          },
          deleteLine: function (cm) {
              deleteNearSelection(cm, function (range) {
                  return {
                      from: Pos(range.from().line, 0),
                      to: clipPos(cm.doc, Pos(range.to().line + 1, 0))
                  };
              });
          },
          delLineLeft: function (cm) {
              deleteNearSelection(cm, function (range) {
                  return {from: Pos(range.from().line, 0), to: range.from()};
              });
          },
          delWrappedLineLeft: function (cm) {
              deleteNearSelection(cm, function (range) {
                  var top = cm.charCoords(range.head, "div").top + 5;
                  var leftPos = cm.coordsChar({left: 0, top: top}, "div");
                  return {from: leftPos, to: range.from()};
              });
          },
          delWrappedLineRight: function (cm) {
              deleteNearSelection(cm, function (range) {
                  var top = cm.charCoords(range.head, "div").top + 5;
                  var rightPos = cm.coordsChar({left: cm.display.lineDiv.offsetWidth + 100, top: top}, "div");
                  return {from: range.from(), to: rightPos};
              });
          },
          undo: function (cm) {
              cm.undo();
          },
          redo: function (cm) {
              cm.redo();
          },
          undoSelection: function (cm) {
              cm.undoSelection();
          },
          redoSelection: function (cm) {
              cm.redoSelection();
          },
          goDocStart: function (cm) {
              cm.extendSelection(Pos(cm.firstLine(), 0));
          },
          goDocEnd: function (cm) {
              cm.extendSelection(Pos(cm.lastLine()));
          },
          goLineStart: function (cm) {
              cm.extendSelectionsBy(function (range) {
                      return lineStart(cm, range.head.line);
                  },
                  {origin: "+move", bias: 1});
          },
          goLineStartSmart: function (cm) {
              cm.extendSelectionsBy(function (range) {
                  return lineStartSmart(cm, range.head);
              }, {origin: "+move", bias: 1});
          },
          goLineEnd: function (cm) {
              cm.extendSelectionsBy(function (range) {
                      return lineEnd(cm, range.head.line);
                  },
                  {origin: "+move", bias: -1});
          },
          goLineRight: function (cm) {
              cm.extendSelectionsBy(function (range) {
                  var top = cm.charCoords(range.head, "div").top + 5;
                  return cm.coordsChar({left: cm.display.lineDiv.offsetWidth + 100, top: top}, "div");
              }, sel_move);
          },
          goLineLeft: function (cm) {
              cm.extendSelectionsBy(function (range) {
                  var top = cm.charCoords(range.head, "div").top + 5;
                  return cm.coordsChar({left: 0, top: top}, "div");
              }, sel_move);
          },
          goLineLeftSmart: function (cm) {
              cm.extendSelectionsBy(function (range) {
                  var top = cm.charCoords(range.head, "div").top + 5;
                  var pos = cm.coordsChar({left: 0, top: top}, "div");
                  if (pos.ch < cm.getLine(pos.line).search(/\S/)) return lineStartSmart(cm, range.head);
                  return pos;
              }, sel_move);
          },
          goLineUp: function (cm) {
              cm.moveV(-1, "line");
          },
          goLineDown: function (cm) {
              cm.moveV(1, "line");
          },
          goPageUp: function (cm) {
              cm.moveV(-1, "page");
          },
          goPageDown: function (cm) {
              cm.moveV(1, "page");
          },
          goCharLeft: function (cm) {
              cm.moveH(-1, "char");
          },
          goCharRight: function (cm) {
              cm.moveH(1, "char");
          },
          goColumnLeft: function (cm) {
              cm.moveH(-1, "column");
          },
          goColumnRight: function (cm) {
              cm.moveH(1, "column");
          },
          goWordLeft: function (cm) {
              cm.moveH(-1, "word");
          },
          goGroupRight: function (cm) {
              cm.moveH(1, "group");
          },
          goGroupLeft: function (cm) {
              cm.moveH(-1, "group");
          },
          goWordRight: function (cm) {
              cm.moveH(1, "word");
          },
          delCharBefore: function (cm) {
              cm.deleteH(-1, "char");
          },
          delCharAfter: function (cm) {
              cm.deleteH(1, "char");
          },
          delWordBefore: function (cm) {
              cm.deleteH(-1, "word");
          },
          delWordAfter: function (cm) {
              cm.deleteH(1, "word");
          },
          delGroupBefore: function (cm) {
              cm.deleteH(-1, "group");
          },
          delGroupAfter: function (cm) {
              cm.deleteH(1, "group");
          },
          indentAuto: function (cm) {
              cm.indentSelection("smart");
          },
          indentMore: function (cm) {
              cm.indentSelection("add");
          },
          indentLess: function (cm) {
              cm.indentSelection("subtract");
          },
          insertTab: function (cm) {
              cm.replaceSelection("\t");
          },
          insertSoftTab: function (cm) {
              var spaces = [], ranges = cm.listSelections(), tabSize = cm.options.tabSize;
              for (var i = 0; i < ranges.length; i++) {
                  var pos = ranges[i].from();
                  var col = countColumn(cm.getLine(pos.line), pos.ch, tabSize);
                  spaces.push(new Array(tabSize - col % tabSize + 1).join(" "));
              }
              cm.replaceSelections(spaces);
          },
          defaultTab: function (cm) {
              if (cm.somethingSelected()) cm.indentSelection("add");
              else cm.execCommand("insertTab");
          },
          transposeChars: function (cm) {
              runInOp(cm, function () {
                  var ranges = cm.listSelections(), newSel = [];
                  for (var i = 0; i < ranges.length; i++) {
                      var cur = ranges[i].head, line = getLine(cm.doc, cur.line).text;
                      if (line) {
                          if (cur.ch == line.length) cur = new Pos(cur.line, cur.ch - 1);
                          if (cur.ch > 0) {
                              cur = new Pos(cur.line, cur.ch + 1);
                              cm.replaceRange(line.charAt(cur.ch - 1) + line.charAt(cur.ch - 2),
                                  Pos(cur.line, cur.ch - 2), cur, "+transpose");
                          } else if (cur.line > cm.doc.first) {
                              var prev = getLine(cm.doc, cur.line - 1).text;
                              if (prev)
                                  cm.replaceRange(line.charAt(0) + "\n" + prev.charAt(prev.length - 1),
                                      Pos(cur.line - 1, prev.length - 1), Pos(cur.line, 1), "+transpose");
                          }
                      }
                      newSel.push(new Range(cur, cur));
                  }
                  cm.setSelections(newSel);
              });
          },
          newlineAndIndent: function (cm) {
              runInOp(cm, function () {
                  var len = cm.listSelections().length;
                  for (var i = 0; i < len; i++) {
                      var range = cm.listSelections()[i];
                      cm.replaceRange("\n", range.anchor, range.head, "+input");
                      cm.indentLine(range.from().line + 1, null, true);
                      ensureCursorVisible(cm);
                  }
              });
          },
          toggleOverwrite: function (cm) {
              cm.toggleOverwrite();
          }
      };
  
  
      // STANDARD KEYMAPS
  
      var keyMap = CodeMirror.keyMap = {};
  
      keyMap.basic = {
          "Left": "goCharLeft", "Right": "goCharRight", "Up": "goLineUp", "Down": "goLineDown",
          "End": "goLineEnd", "Home": "goLineStartSmart", "PageUp": "goPageUp", "PageDown": "goPageDown",
          "Delete": "delCharAfter", "Backspace": "delCharBefore", "Shift-Backspace": "delCharBefore",
          "Tab": "defaultTab", "Shift-Tab": "indentAuto",
          "Enter": "newlineAndIndent", "Insert": "toggleOverwrite",
          "Esc": "singleSelection"
      };
      // Note that the save and find-related commands aren't defined by
      // default. User code or addons can define them. Unknown commands
      // are simply ignored.
      keyMap.pcDefault = {
          "Ctrl-A": "selectAll", "Ctrl-D": "deleteLine", "Ctrl-Z": "undo", "Shift-Ctrl-Z": "redo", "Ctrl-Y": "redo",
          "Ctrl-Home": "goDocStart", "Ctrl-End": "goDocEnd", "Ctrl-Up": "goLineUp", "Ctrl-Down": "goLineDown",
          "Ctrl-Left": "goGroupLeft", "Ctrl-Right": "goGroupRight", "Alt-Left": "goLineStart", "Alt-Right": "goLineEnd",
          "Ctrl-Backspace": "delGroupBefore", "Ctrl-Delete": "delGroupAfter", "Ctrl-S": "save", "Ctrl-F": "find",
          "Ctrl-G": "findNext", "Shift-Ctrl-G": "findPrev", "Shift-Ctrl-F": "replace", "Shift-Ctrl-R": "replaceAll",
          "Ctrl-[": "indentLess", "Ctrl-]": "indentMore",
          "Ctrl-U": "undoSelection", "Shift-Ctrl-U": "redoSelection", "Alt-U": "redoSelection",
          fallthrough: "basic"
      };
      // Very basic readline/emacs-style bindings, which are standard on Mac.
      keyMap.emacsy = {
          "Ctrl-F": "goCharRight", "Ctrl-B": "goCharLeft", "Ctrl-P": "goLineUp", "Ctrl-N": "goLineDown",
          "Alt-F": "goWordRight", "Alt-B": "goWordLeft", "Ctrl-A": "goLineStart", "Ctrl-E": "goLineEnd",
          "Ctrl-V": "goPageDown", "Shift-Ctrl-V": "goPageUp", "Ctrl-D": "delCharAfter", "Ctrl-H": "delCharBefore",
          "Alt-D": "delWordAfter", "Alt-Backspace": "delWordBefore", "Ctrl-K": "killLine", "Ctrl-T": "transposeChars"
      };
      keyMap.macDefault = {
          "Cmd-A": "selectAll",
          "Cmd-D": "deleteLine",
          "Cmd-Z": "undo",
          "Shift-Cmd-Z": "redo",
          "Cmd-Y": "redo",
          "Cmd-Home": "goDocStart",
          "Cmd-Up": "goDocStart",
          "Cmd-End": "goDocEnd",
          "Cmd-Down": "goDocEnd",
          "Alt-Left": "goGroupLeft",
          "Alt-Right": "goGroupRight",
          "Cmd-Left": "goLineLeft",
          "Cmd-Right": "goLineRight",
          "Alt-Backspace": "delGroupBefore",
          "Ctrl-Alt-Backspace": "delGroupAfter",
          "Alt-Delete": "delGroupAfter",
          "Cmd-S": "save",
          "Cmd-F": "find",
          "Cmd-G": "findNext",
          "Shift-Cmd-G": "findPrev",
          "Cmd-Alt-F": "replace",
          "Shift-Cmd-Alt-F": "replaceAll",
          "Cmd-[": "indentLess",
          "Cmd-]": "indentMore",
          "Cmd-Backspace": "delWrappedLineLeft",
          "Cmd-Delete": "delWrappedLineRight",
          "Cmd-U": "undoSelection",
          "Shift-Cmd-U": "redoSelection",
          "Ctrl-Up": "goDocStart",
          "Ctrl-Down": "goDocEnd",
          fallthrough: ["basic", "emacsy"]
      };
      keyMap["default"] = mac ? keyMap.macDefault : keyMap.pcDefault;
  
      // KEYMAP DISPATCH
  
      function normalizeKeyName(name) {
          var parts = name.split(/-(?!$)/), name = parts[parts.length - 1];
          var alt, ctrl, shift, cmd;
          for (var i = 0; i < parts.length - 1; i++) {
              var mod = parts[i];
              if (/^(cmd|meta|m)$/i.test(mod)) cmd = true;
              else if (/^a(lt)?$/i.test(mod)) alt = true;
              else if (/^(c|ctrl|control)$/i.test(mod)) ctrl = true;
              else if (/^s(hift)$/i.test(mod)) shift = true;
              else throw new Error("Unrecognized modifier name: " + mod);
          }
          if (alt) name = "Alt-" + name;
          if (ctrl) name = "Ctrl-" + name;
          if (cmd) name = "Cmd-" + name;
          if (shift) name = "Shift-" + name;
          return name;
      }
  
      // This is a kludge to keep keymaps mostly working as raw objects
      // (backwards compatibility) while at the same time support features
      // like normalization and multi-stroke key bindings. It compiles a
      // new normalized keymap, and then updates the old object to reflect
      // this.
      CodeMirror.normalizeKeyMap = function (keymap) {
          var copy = {};
          for (var keyname in keymap) if (keymap.hasOwnProperty(keyname)) {
              var value = keymap[keyname];
              if (/^(name|fallthrough|(de|at)tach)$/.test(keyname)) continue;
              if (value == "...") {
                  delete keymap[keyname];
                  continue;
              }
  
              var keys = map(keyname.split(" "), normalizeKeyName);
              for (var i = 0; i < keys.length; i++) {
                  var val, name;
                  if (i == keys.length - 1) {
                      name = keyname;
                      val = value;
                  } else {
                      name = keys.slice(0, i + 1).join(" ");
                      val = "...";
                  }
                  var prev = copy[name];
                  if (!prev) copy[name] = val;
                  else if (prev != val) throw new Error("Inconsistent bindings for " + name);
              }
              delete keymap[keyname];
          }
          for (var prop in copy) keymap[prop] = copy[prop];
          return keymap;
      };
  
      var lookupKey = CodeMirror.lookupKey = function (key, map, handle, context) {
          map = getKeyMap(map);
          var found = map.call ? map.call(key, context) : map[key];
          if (found === false) return "nothing";
          if (found === "...") return "multi";
          if (found != null && handle(found)) return "handled";
  
          if (map.fallthrough) {
              if (Object.prototype.toString.call(map.fallthrough) != "[object Array]")
                  return lookupKey(key, map.fallthrough, handle, context);
              for (var i = 0; i < map.fallthrough.length; i++) {
                  var result = lookupKey(key, map.fallthrough[i], handle, context);
                  if (result) return result;
              }
          }
      };
  
      // Modifier key presses don't count as 'real' key presses for the
      // purpose of keymap fallthrough.
      var isModifierKey = CodeMirror.isModifierKey = function (value) {
          var name = typeof value == "string" ? value : keyNames[value.keyCode];
          return name == "Ctrl" || name == "Alt" || name == "Shift" || name == "Mod";
      };
  
      // Look up the name of a key as indicated by an event object.
      var keyName = CodeMirror.keyName = function (event, noShift) {
          if (presto && event.keyCode == 34 && event["char"]) return false;
          var base = keyNames[event.keyCode], name = base;
          if (name == null || event.altGraphKey) return false;
          if (event.altKey && base != "Alt") name = "Alt-" + name;
          if ((flipCtrlCmd ? event.metaKey : event.ctrlKey) && base != "Ctrl") name = "Ctrl-" + name;
          if ((flipCtrlCmd ? event.ctrlKey : event.metaKey) && base != "Cmd") name = "Cmd-" + name;
          if (!noShift && event.shiftKey && base != "Shift") name = "Shift-" + name;
          return name;
      };
  
      function getKeyMap(val) {
          return typeof val == "string" ? keyMap[val] : val;
      }
  
      // FROMTEXTAREA
  
      CodeMirror.fromTextArea = function (textarea, options) {
          options = options ? copyObj(options) : {};
          options.value = textarea.value;
          if (!options.tabindex && textarea.tabIndex)
              options.tabindex = textarea.tabIndex;
          if (!options.placeholder && textarea.placeholder)
              options.placeholder = textarea.placeholder;
          // Set autofocus to true if this textarea is focused, or if it has
          // autofocus and no other element is focused.
          if (options.autofocus == null) {
              var hasFocus = activeElt();
              options.autofocus = hasFocus == textarea ||
                  textarea.getAttribute("autofocus") != null && hasFocus == document.body;
          }
  
          function save() {
              textarea.value = cm.getValue();
          }
  
          if (textarea.form) {
              on(textarea.form, "submit", save);
              // Deplorable hack to make the submit method do the right thing.
              if (!options.leaveSubmitMethodAlone) {
                  var form = textarea.form, realSubmit = form.submit;
                  try {
                      var wrappedSubmit = form.submit = function () {
                          save();
                          form.submit = realSubmit;
                          form.submit();
                          form.submit = wrappedSubmit;
                      };
                  } catch (e) {
                  }
              }
          }
  
          options.finishInit = function (cm) {
              cm.save = save;
              cm.getTextArea = function () {
                  return textarea;
              };
              cm.toTextArea = function () {
                  cm.toTextArea = isNaN; // Prevent this from being ran twice
                  save();
                  textarea.parentNode.removeChild(cm.getWrapperElement());
                  textarea.style.display = "";
                  if (textarea.form) {
                      off(textarea.form, "submit", save);
                      if (typeof textarea.form.submit == "function")
                          textarea.form.submit = realSubmit;
                  }
              };
          };
  
          textarea.style.display = "none";
          var cm = CodeMirror(function (node) {
              textarea.parentNode.insertBefore(node, textarea.nextSibling);
          }, options);
          return cm;
      };
  
      // STRING STREAM
  
      // Fed to the mode parsers, provides helper functions to make
      // parsers more succinct.
  
      var StringStream = CodeMirror.StringStream = function (string, tabSize) {
          this.pos = this.start = 0;
          this.string = string;
          this.tabSize = tabSize || 8;
          this.lastColumnPos = this.lastColumnValue = 0;
          this.lineStart = 0;
      };
  
      StringStream.prototype = {
          eol: function () {
              return this.pos >= this.string.length;
          },
          sol: function () {
              return this.pos == this.lineStart;
          },
          peek: function () {
              return this.string.charAt(this.pos) || undefined;
          },
          next: function () {
              if (this.pos < this.string.length)
                  return this.string.charAt(this.pos++);
          },
          eat: function (match) {
              var ch = this.string.charAt(this.pos);
              if (typeof match == "string") var ok = ch == match;
              else var ok = ch && (match.test ? match.test(ch) : match(ch));
              if (ok) {
                  ++this.pos;
                  return ch;
              }
          },
          eatWhile: function (match) {
              var start = this.pos;
              while (this.eat(match)) {
              }
              return this.pos > start;
          },
          eatSpace: function () {
              var start = this.pos;
              while (/[\s\u00a0]/.test(this.string.charAt(this.pos))) ++this.pos;
              return this.pos > start;
          },
          skipToEnd: function () {
              this.pos = this.string.length;
          },
          skipTo: function (ch) {
              var found = this.string.indexOf(ch, this.pos);
              if (found > -1) {
                  this.pos = found;
                  return true;
              }
          },
          backUp: function (n) {
              this.pos -= n;
          },
          column: function () {
              if (this.lastColumnPos < this.start) {
                  this.lastColumnValue = countColumn(this.string, this.start, this.tabSize, this.lastColumnPos, this.lastColumnValue);
                  this.lastColumnPos = this.start;
              }
              return this.lastColumnValue - (this.lineStart ? countColumn(this.string, this.lineStart, this.tabSize) : 0);
          },
          indentation: function () {
              return countColumn(this.string, null, this.tabSize) -
                  (this.lineStart ? countColumn(this.string, this.lineStart, this.tabSize) : 0);
          },
          match: function (pattern, consume, caseInsensitive) {
              if (typeof pattern == "string") {
                  var cased = function (str) {
                      return caseInsensitive ? str.toLowerCase() : str;
                  };
                  var substr = this.string.substr(this.pos, pattern.length);
                  if (cased(substr) == cased(pattern)) {
                      if (consume !== false) this.pos += pattern.length;
                      return true;
                  }
              } else {
                  var match = this.string.slice(this.pos).match(pattern);
                  if (match && match.index > 0) return null;
                  if (match && consume !== false) this.pos += match[0].length;
                  return match;
              }
          },
          current: function () {
              return this.string.slice(this.start, this.pos);
          },
          hideFirstChars: function (n, inner) {
              this.lineStart += n;
              try {
                  return inner();
              }
              finally {
                  this.lineStart -= n;
              }
          }
      };
  
      // TEXTMARKERS
  
      // Created with markText and setBookmark methods. A TextMarker is a
      // handle that can be used to clear or find a marked position in the
      // document. Line objects hold arrays (markedSpans) containing
      // {from, to, marker} object pointing to such marker objects, and
      // indicating that such a marker is present on that line. Multiple
      // lines may point to the same marker when it spans across lines.
      // The spans will have null for their from/to properties when the
      // marker continues beyond the start/end of the line. Markers have
      // links back to the lines they currently touch.
  
      var nextMarkerId = 0;
  
      var TextMarker = CodeMirror.TextMarker = function (doc, type) {
          this.lines = [];
          this.type = type;
          this.doc = doc;
          this.id = ++nextMarkerId;
      };
      eventMixin(TextMarker);
  
      // Clear the marker.
      TextMarker.prototype.clear = function () {
          if (this.explicitlyCleared) return;
          var cm = this.doc.cm, withOp = cm && !cm.curOp;
          if (withOp) startOperation(cm);
          if (hasHandler(this, "clear")) {
              var found = this.find();
              if (found) signalLater(this, "clear", found.from, found.to);
          }
          var min = null, max = null;
          for (var i = 0; i < this.lines.length; ++i) {
              var line = this.lines[i];
              var span = getMarkedSpanFor(line.markedSpans, this);
              if (cm && !this.collapsed) regLineChange(cm, lineNo(line), "text");
              else if (cm) {
                  if (span.to != null) max = lineNo(line);
                  if (span.from != null) min = lineNo(line);
              }
              line.markedSpans = removeMarkedSpan(line.markedSpans, span);
              if (span.from == null && this.collapsed && !lineIsHidden(this.doc, line) && cm)
                  updateLineHeight(line, textHeight(cm.display));
          }
          if (cm && this.collapsed && !cm.options.lineWrapping) for (var i = 0; i < this.lines.length; ++i) {
              var visual = visualLine(this.lines[i]), len = lineLength(visual);
              if (len > cm.display.maxLineLength) {
                  cm.display.maxLine = visual;
                  cm.display.maxLineLength = len;
                  cm.display.maxLineChanged = true;
              }
          }
  
          if (min != null && cm && this.collapsed) regChange(cm, min, max + 1);
          this.lines.length = 0;
          this.explicitlyCleared = true;
          if (this.atomic && this.doc.cantEdit) {
              this.doc.cantEdit = false;
              if (cm) reCheckSelection(cm.doc);
          }
          if (cm) signalLater(cm, "markerCleared", cm, this);
          if (withOp) endOperation(cm);
          if (this.parent) this.parent.clear();
      };
  
      // Find the position of the marker in the document. Returns a {from,
      // to} object by default. Side can be passed to get a specific side
      // -- 0 (both), -1 (left), or 1 (right). When lineObj is true, the
      // Pos objects returned contain a line object, rather than a line
      // number (used to prevent looking up the same line twice).
      TextMarker.prototype.find = function (side, lineObj) {
          if (side == null && this.type == "bookmark") side = 1;
          var from, to;
          for (var i = 0; i < this.lines.length; ++i) {
              var line = this.lines[i];
              var span = getMarkedSpanFor(line.markedSpans, this);
              if (span.from != null) {
                  from = Pos(lineObj ? line : lineNo(line), span.from);
                  if (side == -1) return from;
              }
              if (span.to != null) {
                  to = Pos(lineObj ? line : lineNo(line), span.to);
                  if (side == 1) return to;
              }
          }
          return from && {from: from, to: to};
      };
  
      // Signals that the marker's widget changed, and surrounding layout
      // should be recomputed.
      TextMarker.prototype.changed = function () {
          var pos = this.find(-1, true), widget = this, cm = this.doc.cm;
          if (!pos || !cm) return;
          runInOp(cm, function () {
              var line = pos.line, lineN = lineNo(pos.line);
              var view = findViewForLine(cm, lineN);
              if (view) {
                  clearLineMeasurementCacheFor(view);
                  cm.curOp.selectionChanged = cm.curOp.forceUpdate = true;
              }
              cm.curOp.updateMaxLine = true;
              if (!lineIsHidden(widget.doc, line) && widget.height != null) {
                  var oldHeight = widget.height;
                  widget.height = null;
                  var dHeight = widgetHeight(widget) - oldHeight;
                  if (dHeight)
                      updateLineHeight(line, line.height + dHeight);
              }
          });
      };
  
      TextMarker.prototype.attachLine = function (line) {
          if (!this.lines.length && this.doc.cm) {
              var op = this.doc.cm.curOp;
              if (!op.maybeHiddenMarkers || indexOf(op.maybeHiddenMarkers, this) == -1)
                  (op.maybeUnhiddenMarkers || (op.maybeUnhiddenMarkers = [])).push(this);
          }
          this.lines.push(line);
      };
      TextMarker.prototype.detachLine = function (line) {
          this.lines.splice(indexOf(this.lines, line), 1);
          if (!this.lines.length && this.doc.cm) {
              var op = this.doc.cm.curOp;
              (op.maybeHiddenMarkers || (op.maybeHiddenMarkers = [])).push(this);
          }
      };
  
      // Collapsed markers have unique ids, in order to be able to order
      // them, which is needed for uniquely determining an outer marker
      // when they overlap (they may nest, but not partially overlap).
      var nextMarkerId = 0;
  
      // Create a marker, wire it up to the right lines, and
      function markText(doc, from, to, options, type) {
          // Shared markers (across linked documents) are handled separately
          // (markTextShared will call out to this again, once per
          // document).
          if (options && options.shared) return markTextShared(doc, from, to, options, type);
          // Ensure we are in an operation.
          if (doc.cm && !doc.cm.curOp) return operation(doc.cm, markText)(doc, from, to, options, type);
  
          var marker = new TextMarker(doc, type), diff = cmp(from, to);
          if (options) copyObj(options, marker, false);
          // Don't connect empty markers unless clearWhenEmpty is false
          if (diff > 0 || diff == 0 && marker.clearWhenEmpty !== false)
              return marker;
          if (marker.replacedWith) {
              // Showing up as a widget implies collapsed (widget replaces text)
              marker.collapsed = true;
              marker.widgetNode = elt("span", [marker.replacedWith], "CodeMirror-widget");
              if (!options.handleMouseEvents) marker.widgetNode.setAttribute("cm-ignore-events", "true");
              if (options.insertLeft) marker.widgetNode.insertLeft = true;
          }
          if (marker.collapsed) {
              if (conflictingCollapsedRange(doc, from.line, from, to, marker) ||
                  from.line != to.line && conflictingCollapsedRange(doc, to.line, from, to, marker))
                  throw new Error("Inserting collapsed marker partially overlapping an existing one");
              sawCollapsedSpans = true;
          }
  
          if (marker.addToHistory)
              addChangeToHistory(doc, {from: from, to: to, origin: "markText"}, doc.sel, NaN);
  
          var curLine = from.line, cm = doc.cm, updateMaxLine;
          doc.iter(curLine, to.line + 1, function (line) {
              if (cm && marker.collapsed && !cm.options.lineWrapping && visualLine(line) == cm.display.maxLine)
                  updateMaxLine = true;
              if (marker.collapsed && curLine != from.line) updateLineHeight(line, 0);
              addMarkedSpan(line, new MarkedSpan(marker,
                  curLine == from.line ? from.ch : null,
                  curLine == to.line ? to.ch : null));
              ++curLine;
          });
          // lineIsHidden depends on the presence of the spans, so needs a second pass
          if (marker.collapsed) doc.iter(from.line, to.line + 1, function (line) {
              if (lineIsHidden(doc, line)) updateLineHeight(line, 0);
          });
  
          if (marker.clearOnEnter) on(marker, "beforeCursorEnter", function () {
              marker.clear();
          });
  
          if (marker.readOnly) {
              sawReadOnlySpans = true;
              if (doc.history.done.length || doc.history.undone.length)
                  doc.clearHistory();
          }
          if (marker.collapsed) {
              marker.id = ++nextMarkerId;
              marker.atomic = true;
          }
          if (cm) {
              // Sync editor state
              if (updateMaxLine) cm.curOp.updateMaxLine = true;
              if (marker.collapsed)
                  regChange(cm, from.line, to.line + 1);
              else if (marker.className || marker.title || marker.startStyle || marker.endStyle || marker.css)
                  for (var i = from.line; i <= to.line; i++) regLineChange(cm, i, "text");
              if (marker.atomic) reCheckSelection(cm.doc);
              signalLater(cm, "markerAdded", cm, marker);
          }
          return marker;
      }
  
      // SHARED TEXTMARKERS
  
      // A shared marker spans multiple linked documents. It is
      // implemented as a meta-marker-object controlling multiple normal
      // markers.
      var SharedTextMarker = CodeMirror.SharedTextMarker = function (markers, primary) {
          this.markers = markers;
          this.primary = primary;
          for (var i = 0; i < markers.length; ++i)
              markers[i].parent = this;
      };
      eventMixin(SharedTextMarker);
  
      SharedTextMarker.prototype.clear = function () {
          if (this.explicitlyCleared) return;
          this.explicitlyCleared = true;
          for (var i = 0; i < this.markers.length; ++i)
              this.markers[i].clear();
          signalLater(this, "clear");
      };
      SharedTextMarker.prototype.find = function (side, lineObj) {
          return this.primary.find(side, lineObj);
      };
  
      function markTextShared(doc, from, to, options, type) {
          options = copyObj(options);
          options.shared = false;
          var markers = [markText(doc, from, to, options, type)], primary = markers[0];
          var widget = options.widgetNode;
          linkedDocs(doc, function (doc) {
              if (widget) options.widgetNode = widget.cloneNode(true);
              markers.push(markText(doc, clipPos(doc, from), clipPos(doc, to), options, type));
              for (var i = 0; i < doc.linked.length; ++i)
                  if (doc.linked[i].isParent) return;
              primary = lst(markers);
          });
          return new SharedTextMarker(markers, primary);
      }
  
      function findSharedMarkers(doc) {
          return doc.findMarks(Pos(doc.first, 0), doc.clipPos(Pos(doc.lastLine())),
              function (m) {
                  return m.parent;
              });
      }
  
      function copySharedMarkers(doc, markers) {
          for (var i = 0; i < markers.length; i++) {
              var marker = markers[i], pos = marker.find();
              var mFrom = doc.clipPos(pos.from), mTo = doc.clipPos(pos.to);
              if (cmp(mFrom, mTo)) {
                  var subMark = markText(doc, mFrom, mTo, marker.primary, marker.primary.type);
                  marker.markers.push(subMark);
                  subMark.parent = marker;
              }
          }
      }
  
      function detachSharedMarkers(markers) {
          for (var i = 0; i < markers.length; i++) {
              var marker = markers[i], linked = [marker.primary.doc];
              ;
              linkedDocs(marker.primary.doc, function (d) {
                  linked.push(d);
              });
              for (var j = 0; j < marker.markers.length; j++) {
                  var subMarker = marker.markers[j];
                  if (indexOf(linked, subMarker.doc) == -1) {
                      subMarker.parent = null;
                      marker.markers.splice(j--, 1);
                  }
              }
          }
      }
  
      // TEXTMARKER SPANS
  
      function MarkedSpan(marker, from, to) {
          this.marker = marker;
          this.from = from;
          this.to = to;
      }
  
      // Search an array of spans for a span matching the given marker.
      function getMarkedSpanFor(spans, marker) {
          if (spans) for (var i = 0; i < spans.length; ++i) {
              var span = spans[i];
              if (span.marker == marker) return span;
          }
      }
  
      // Remove a span from an array, returning undefined if no spans are
      // left (we don't store arrays for lines without spans).
      function removeMarkedSpan(spans, span) {
          for (var r, i = 0; i < spans.length; ++i)
              if (spans[i] != span) (r || (r = [])).push(spans[i]);
          return r;
      }
  
      // Add a span to a line.
      function addMarkedSpan(line, span) {
          line.markedSpans = line.markedSpans ? line.markedSpans.concat([span]) : [span];
          span.marker.attachLine(line);
      }
  
      // Used for the algorithm that adjusts markers for a change in the
      // document. These functions cut an array of spans at a given
      // character position, returning an array of remaining chunks (or
      // undefined if nothing remains).
      function markedSpansBefore(old, startCh, isInsert) {
          if (old) for (var i = 0, nw; i < old.length; ++i) {
              var span = old[i], marker = span.marker;
              var startsBefore = span.from == null || (marker.inclusiveLeft ? span.from <= startCh : span.from < startCh);
              if (startsBefore || span.from == startCh && marker.type == "bookmark" && (!isInsert || !span.marker.insertLeft)) {
                  var endsAfter = span.to == null || (marker.inclusiveRight ? span.to >= startCh : span.to > startCh);
                  (nw || (nw = [])).push(new MarkedSpan(marker, span.from, endsAfter ? null : span.to));
              }
          }
          return nw;
      }
  
      function markedSpansAfter(old, endCh, isInsert) {
          if (old) for (var i = 0, nw; i < old.length; ++i) {
              var span = old[i], marker = span.marker;
              var endsAfter = span.to == null || (marker.inclusiveRight ? span.to >= endCh : span.to > endCh);
              if (endsAfter || span.from == endCh && marker.type == "bookmark" && (!isInsert || span.marker.insertLeft)) {
                  var startsBefore = span.from == null || (marker.inclusiveLeft ? span.from <= endCh : span.from < endCh);
                  (nw || (nw = [])).push(new MarkedSpan(marker, startsBefore ? null : span.from - endCh,
                      span.to == null ? null : span.to - endCh));
              }
          }
          return nw;
      }
  
      // Given a change object, compute the new set of marker spans that
      // cover the line in which the change took place. Removes spans
      // entirely within the change, reconnects spans belonging to the
      // same marker that appear on both sides of the change, and cuts off
      // spans partially within the change. Returns an array of span
      // arrays with one element for each line in (after) the change.
      function stretchSpansOverChange(doc, change) {
          if (change.full) return null;
          var oldFirst = isLine(doc, change.from.line) && getLine(doc, change.from.line).markedSpans;
          var oldLast = isLine(doc, change.to.line) && getLine(doc, change.to.line).markedSpans;
          if (!oldFirst && !oldLast) return null;
  
          var startCh = change.from.ch, endCh = change.to.ch, isInsert = cmp(change.from, change.to) == 0;
          // Get the spans that 'stick out' on both sides
          var first = markedSpansBefore(oldFirst, startCh, isInsert);
          var last = markedSpansAfter(oldLast, endCh, isInsert);
  
          // Next, merge those two ends
          var sameLine = change.text.length == 1, offset = lst(change.text).length + (sameLine ? startCh : 0);
          if (first) {
              // Fix up .to properties of first
              for (var i = 0; i < first.length; ++i) {
                  var span = first[i];
                  if (span.to == null) {
                      var found = getMarkedSpanFor(last, span.marker);
                      if (!found) span.to = startCh;
                      else if (sameLine) span.to = found.to == null ? null : found.to + offset;
                  }
              }
          }
          if (last) {
              // Fix up .from in last (or move them into first in case of sameLine)
              for (var i = 0; i < last.length; ++i) {
                  var span = last[i];
                  if (span.to != null) span.to += offset;
                  if (span.from == null) {
                      var found = getMarkedSpanFor(first, span.marker);
                      if (!found) {
                          span.from = offset;
                          if (sameLine) (first || (first = [])).push(span);
                      }
                  } else {
                      span.from += offset;
                      if (sameLine) (first || (first = [])).push(span);
                  }
              }
          }
          // Make sure we didn't create any zero-length spans
          if (first) first = clearEmptySpans(first);
          if (last && last != first) last = clearEmptySpans(last);
  
          var newMarkers = [first];
          if (!sameLine) {
              // Fill gap with whole-line-spans
              var gap = change.text.length - 2, gapMarkers;
              if (gap > 0 && first)
                  for (var i = 0; i < first.length; ++i)
                      if (first[i].to == null)
                          (gapMarkers || (gapMarkers = [])).push(new MarkedSpan(first[i].marker, null, null));
              for (var i = 0; i < gap; ++i)
                  newMarkers.push(gapMarkers);
              newMarkers.push(last);
          }
          return newMarkers;
      }
  
      // Remove spans that are empty and don't have a clearWhenEmpty
      // option of false.
      function clearEmptySpans(spans) {
          for (var i = 0; i < spans.length; ++i) {
              var span = spans[i];
              if (span.from != null && span.from == span.to && span.marker.clearWhenEmpty !== false)
                  spans.splice(i--, 1);
          }
          if (!spans.length) return null;
          return spans;
      }
  
      // Used for un/re-doing changes from the history. Combines the
      // result of computing the existing spans with the set of spans that
      // existed in the history (so that deleting around a span and then
      // undoing brings back the span).
      function mergeOldSpans(doc, change) {
          var old = getOldSpans(doc, change);
          var stretched = stretchSpansOverChange(doc, change);
          if (!old) return stretched;
          if (!stretched) return old;
  
          for (var i = 0; i < old.length; ++i) {
              var oldCur = old[i], stretchCur = stretched[i];
              if (oldCur && stretchCur) {
                  spans: for (var j = 0; j < stretchCur.length; ++j) {
                      var span = stretchCur[j];
                      for (var k = 0; k < oldCur.length; ++k)
                          if (oldCur[k].marker == span.marker) continue spans;
                      oldCur.push(span);
                  }
              } else if (stretchCur) {
                  old[i] = stretchCur;
              }
          }
          return old;
      }
  
      // Used to 'clip' out readOnly ranges when making a change.
      function removeReadOnlyRanges(doc, from, to) {
          var markers = null;
          doc.iter(from.line, to.line + 1, function (line) {
              if (line.markedSpans) for (var i = 0; i < line.markedSpans.length; ++i) {
                  var mark = line.markedSpans[i].marker;
                  if (mark.readOnly && (!markers || indexOf(markers, mark) == -1))
                      (markers || (markers = [])).push(mark);
              }
          });
          if (!markers) return null;
          var parts = [{from: from, to: to}];
          for (var i = 0; i < markers.length; ++i) {
              var mk = markers[i], m = mk.find(0);
              for (var j = 0; j < parts.length; ++j) {
                  var p = parts[j];
                  if (cmp(p.to, m.from) < 0 || cmp(p.from, m.to) > 0) continue;
                  var newParts = [j, 1], dfrom = cmp(p.from, m.from), dto = cmp(p.to, m.to);
                  if (dfrom < 0 || !mk.inclusiveLeft && !dfrom)
                      newParts.push({from: p.from, to: m.from});
                  if (dto > 0 || !mk.inclusiveRight && !dto)
                      newParts.push({from: m.to, to: p.to});
                  parts.splice.apply(parts, newParts);
                  j += newParts.length - 1;
              }
          }
          return parts;
      }
  
      // Connect or disconnect spans from a line.
      function detachMarkedSpans(line) {
          var spans = line.markedSpans;
          if (!spans) return;
          for (var i = 0; i < spans.length; ++i)
              spans[i].marker.detachLine(line);
          line.markedSpans = null;
      }
  
      function attachMarkedSpans(line, spans) {
          if (!spans) return;
          for (var i = 0; i < spans.length; ++i)
              spans[i].marker.attachLine(line);
          line.markedSpans = spans;
      }
  
      // Helpers used when computing which overlapping collapsed span
      // counts as the larger one.
      function extraLeft(marker) {
          return marker.inclusiveLeft ? -1 : 0;
      }
  
      function extraRight(marker) {
          return marker.inclusiveRight ? 1 : 0;
      }
  
      // Returns a number indicating which of two overlapping collapsed
      // spans is larger (and thus includes the other). Falls back to
      // comparing ids when the spans cover exactly the same range.
      function compareCollapsedMarkers(a, b) {
          var lenDiff = a.lines.length - b.lines.length;
          if (lenDiff != 0) return lenDiff;
          var aPos = a.find(), bPos = b.find();
          var fromCmp = cmp(aPos.from, bPos.from) || extraLeft(a) - extraLeft(b);
          if (fromCmp) return -fromCmp;
          var toCmp = cmp(aPos.to, bPos.to) || extraRight(a) - extraRight(b);
          if (toCmp) return toCmp;
          return b.id - a.id;
      }
  
      // Find out whether a line ends or starts in a collapsed span. If
      // so, return the marker for that span.
      function collapsedSpanAtSide(line, start) {
          var sps = sawCollapsedSpans && line.markedSpans, found;
          if (sps) for (var sp, i = 0; i < sps.length; ++i) {
              sp = sps[i];
              if (sp.marker.collapsed && (start ? sp.from : sp.to) == null &&
                  (!found || compareCollapsedMarkers(found, sp.marker) < 0))
                  found = sp.marker;
          }
          return found;
      }
  
      function collapsedSpanAtStart(line) {
          return collapsedSpanAtSide(line, true);
      }
  
      function collapsedSpanAtEnd(line) {
          return collapsedSpanAtSide(line, false);
      }
  
      // Test whether there exists a collapsed span that partially
      // overlaps (covers the start or end, but not both) of a new span.
      // Such overlap is not allowed.
      function conflictingCollapsedRange(doc, lineNo, from, to, marker) {
          var line = getLine(doc, lineNo);
          var sps = sawCollapsedSpans && line.markedSpans;
          if (sps) for (var i = 0; i < sps.length; ++i) {
              var sp = sps[i];
              if (!sp.marker.collapsed) continue;
              var found = sp.marker.find(0);
              var fromCmp = cmp(found.from, from) || extraLeft(sp.marker) - extraLeft(marker);
              var toCmp = cmp(found.to, to) || extraRight(sp.marker) - extraRight(marker);
              if (fromCmp >= 0 && toCmp <= 0 || fromCmp <= 0 && toCmp >= 0) continue;
              if (fromCmp <= 0 && (cmp(found.to, from) > 0 || (sp.marker.inclusiveRight && marker.inclusiveLeft)) ||
                  fromCmp >= 0 && (cmp(found.from, to) < 0 || (sp.marker.inclusiveLeft && marker.inclusiveRight)))
                  return true;
          }
      }
  
      // A visual line is a line as drawn on the screen. Folding, for
      // example, can cause multiple logical lines to appear on the same
      // visual line. This finds the start of the visual line that the
      // given line is part of (usually that is the line itself).
      function visualLine(line) {
          var merged;
          while (merged = collapsedSpanAtStart(line))
              line = merged.find(-1, true).line;
          return line;
      }
  
      // Returns an array of logical lines that continue the visual line
      // started by the argument, or undefined if there are no such lines.
      function visualLineContinued(line) {
          var merged, lines;
          while (merged = collapsedSpanAtEnd(line)) {
              line = merged.find(1, true).line;
              (lines || (lines = [])).push(line);
          }
          return lines;
      }
  
      // Get the line number of the start of the visual line that the
      // given line number is part of.
      function visualLineNo(doc, lineN) {
          var line = getLine(doc, lineN), vis = visualLine(line);
          if (line == vis) return lineN;
          return lineNo(vis);
      }
  
      // Get the line number of the start of the next visual line after
      // the given line.
      function visualLineEndNo(doc, lineN) {
          if (lineN > doc.lastLine()) return lineN;
          var line = getLine(doc, lineN), merged;
          if (!lineIsHidden(doc, line)) return lineN;
          while (merged = collapsedSpanAtEnd(line))
              line = merged.find(1, true).line;
          return lineNo(line) + 1;
      }
  
      // Compute whether a line is hidden. Lines count as hidden when they
      // are part of a visual line that starts with another line, or when
      // they are entirely covered by collapsed, non-widget span.
      function lineIsHidden(doc, line) {
          var sps = sawCollapsedSpans && line.markedSpans;
          if (sps) for (var sp, i = 0; i < sps.length; ++i) {
              sp = sps[i];
              if (!sp.marker.collapsed) continue;
              if (sp.from == null) return true;
              if (sp.marker.widgetNode) continue;
              if (sp.from == 0 && sp.marker.inclusiveLeft && lineIsHiddenInner(doc, line, sp))
                  return true;
          }
      }
  
      function lineIsHiddenInner(doc, line, span) {
          if (span.to == null) {
              var end = span.marker.find(1, true);
              return lineIsHiddenInner(doc, end.line, getMarkedSpanFor(end.line.markedSpans, span.marker));
          }
          if (span.marker.inclusiveRight && span.to == line.text.length)
              return true;
          for (var sp, i = 0; i < line.markedSpans.length; ++i) {
              sp = line.markedSpans[i];
              if (sp.marker.collapsed && !sp.marker.widgetNode && sp.from == span.to &&
                  (sp.to == null || sp.to != span.from) &&
                  (sp.marker.inclusiveLeft || span.marker.inclusiveRight) &&
                  lineIsHiddenInner(doc, line, sp)) return true;
          }
      }
  
      // LINE WIDGETS
  
      // Line widgets are block elements displayed above or below a line.
  
      var LineWidget = CodeMirror.LineWidget = function (cm, node, options) {
          if (options) for (var opt in options) if (options.hasOwnProperty(opt))
              this[opt] = options[opt];
          this.cm = cm;
          this.node = node;
      };
      eventMixin(LineWidget);
  
      function adjustScrollWhenAboveVisible(cm, line, diff) {
          if (heightAtLine(line) < ((cm.curOp && cm.curOp.scrollTop) || cm.doc.scrollTop))
              addToScrollPos(cm, null, diff);
      }
  
      LineWidget.prototype.clear = function () {
          var cm = this.cm, ws = this.line.widgets, line = this.line, no = lineNo(line);
          if (no == null || !ws) return;
          for (var i = 0; i < ws.length; ++i) if (ws[i] == this) ws.splice(i--, 1);
          if (!ws.length) line.widgets = null;
          var height = widgetHeight(this);
          runInOp(cm, function () {
              adjustScrollWhenAboveVisible(cm, line, -height);
              regLineChange(cm, no, "widget");
              updateLineHeight(line, Math.max(0, line.height - height));
          });
      };
      LineWidget.prototype.changed = function () {
          var oldH = this.height, cm = this.cm, line = this.line;
          this.height = null;
          var diff = widgetHeight(this) - oldH;
          if (!diff) return;
          runInOp(cm, function () {
              cm.curOp.forceUpdate = true;
              adjustScrollWhenAboveVisible(cm, line, diff);
              updateLineHeight(line, line.height + diff);
          });
      };
  
      function widgetHeight(widget) {
          if (widget.height != null) return widget.height;
          if (!contains(document.body, widget.node)) {
              var parentStyle = "position: relative;";
              if (widget.coverGutter)
                  parentStyle += "margin-left: -" + widget.cm.display.gutters.offsetWidth + "px;";
              if (widget.noHScroll)
                  parentStyle += "width: " + widget.cm.display.wrapper.clientWidth + "px;";
              removeChildrenAndAdd(widget.cm.display.measure, elt("div", [widget.node], null, parentStyle));
          }
          return widget.height = widget.node.offsetHeight;
      }
  
      function addLineWidget(cm, handle, node, options) {
          var widget = new LineWidget(cm, node, options);
          if (widget.noHScroll) cm.display.alignWidgets = true;
          changeLine(cm.doc, handle, "widget", function (line) {
              var widgets = line.widgets || (line.widgets = []);
              if (widget.insertAt == null) widgets.push(widget);
              else widgets.splice(Math.min(widgets.length - 1, Math.max(0, widget.insertAt)), 0, widget);
              widget.line = line;
              if (!lineIsHidden(cm.doc, line)) {
                  var aboveVisible = heightAtLine(line) < cm.doc.scrollTop;
                  updateLineHeight(line, line.height + widgetHeight(widget));
                  if (aboveVisible) addToScrollPos(cm, null, widget.height);
                  cm.curOp.forceUpdate = true;
              }
              return true;
          });
          return widget;
      }
  
      // LINE DATA STRUCTURE
  
      // Line objects. These hold state related to a line, including
      // highlighting info (the styles array).
      var Line = CodeMirror.Line = function (text, markedSpans, estimateHeight) {
          this.text = text;
          attachMarkedSpans(this, markedSpans);
          this.height = estimateHeight ? estimateHeight(this) : 1;
      };
      eventMixin(Line);
      Line.prototype.lineNo = function () {
          return lineNo(this);
      };
  
      // Change the content (text, markers) of a line. Automatically
      // invalidates cached information and tries to re-estimate the
      // line's height.
      function updateLine(line, text, markedSpans, estimateHeight) {
          line.text = text;
          if (line.stateAfter) line.stateAfter = null;
          if (line.styles) line.styles = null;
          if (line.order != null) line.order = null;
          detachMarkedSpans(line);
          attachMarkedSpans(line, markedSpans);
          var estHeight = estimateHeight ? estimateHeight(line) : 1;
          if (estHeight != line.height) updateLineHeight(line, estHeight);
      }
  
      // Detach a line from the document tree and its markers.
      function cleanUpLine(line) {
          line.parent = null;
          detachMarkedSpans(line);
      }
  
      function extractLineClasses(type, output) {
          if (type) for (; ;) {
              var lineClass = type.match(/(?:^|\s+)line-(background-)?(\S+)/);
              if (!lineClass) break;
              type = type.slice(0, lineClass.index) + type.slice(lineClass.index + lineClass[0].length);
              var prop = lineClass[1] ? "bgClass" : "textClass";
              if (output[prop] == null)
                  output[prop] = lineClass[2];
              else if (!(new RegExp("(?:^|\s)" + lineClass[2] + "(?:$|\s)")).test(output[prop]))
                  output[prop] += " " + lineClass[2];
          }
          return type;
      }
  
      function callBlankLine(mode, state) {
          if (mode.blankLine) return mode.blankLine(state);
          if (!mode.innerMode) return;
          var inner = CodeMirror.innerMode(mode, state);
          if (inner.mode.blankLine) return inner.mode.blankLine(inner.state);
      }
  
      function readToken(mode, stream, state, inner) {
          for (var i = 0; i < 10; i++) {
              if (inner) inner[0] = CodeMirror.innerMode(mode, state).mode;
              var style = mode.token(stream, state);
              if (stream.pos > stream.start) return style;
          }
          throw new Error("Mode " + mode.name + " failed to advance stream.");
      }
  
      // Utility for getTokenAt and getLineTokens
      function takeToken(cm, pos, precise, asArray) {
          function getObj(copy) {
              return {
                  start: stream.start, end: stream.pos,
                  string: stream.current(),
                  type: style || null,
                  state: copy ? copyState(doc.mode, state) : state
              };
          }
  
          var doc = cm.doc, mode = doc.mode, style;
          pos = clipPos(doc, pos);
          var line = getLine(doc, pos.line), state = getStateBefore(cm, pos.line, precise);
          var stream = new StringStream(line.text, cm.options.tabSize), tokens;
          if (asArray) tokens = [];
          while ((asArray || stream.pos < pos.ch) && !stream.eol()) {
              stream.start = stream.pos;
              style = readToken(mode, stream, state);
              if (asArray) tokens.push(getObj(true));
          }
          return asArray ? tokens : getObj();
      }
  
      // Run the given mode's parser over a line, calling f for each token.
      function runMode(cm, text, mode, state, f, lineClasses, forceToEnd) {
          var flattenSpans = mode.flattenSpans;
          if (flattenSpans == null) flattenSpans = cm.options.flattenSpans;
          var curStart = 0, curStyle = null;
          var stream = new StringStream(text, cm.options.tabSize), style;
          var inner = cm.options.addModeClass && [null];
          if (text == "") extractLineClasses(callBlankLine(mode, state), lineClasses);
          while (!stream.eol()) {
              if (stream.pos > cm.options.maxHighlightLength) {
                  flattenSpans = false;
                  if (forceToEnd) processLine(cm, text, state, stream.pos);
                  stream.pos = text.length;
                  style = null;
              } else {
                  style = extractLineClasses(readToken(mode, stream, state, inner), lineClasses);
              }
              if (inner) {
                  var mName = inner[0].name;
                  if (mName) style = "m-" + (style ? mName + " " + style : mName);
              }
              if (!flattenSpans || curStyle != style) {
                  while (curStart < stream.start) {
                      curStart = Math.min(stream.start, curStart + 50000);
                      f(curStart, curStyle);
                  }
                  curStyle = style;
              }
              stream.start = stream.pos;
          }
          while (curStart < stream.pos) {
              // Webkit seems to refuse to render text nodes longer than 57444 characters
              var pos = Math.min(stream.pos, curStart + 50000);
              f(pos, curStyle);
              curStart = pos;
          }
      }
  
      // Compute a style array (an array starting with a mode generation
      // -- for invalidation -- followed by pairs of end positions and
      // style strings), which is used to highlight the tokens on the
      // line.
      function highlightLine(cm, line, state, forceToEnd) {
          // A styles array always starts with a number identifying the
          // mode/overlays that it is based on (for easy invalidation).
          var st = [cm.state.modeGen], lineClasses = {};
          // Compute the base array of styles
          runMode(cm, line.text, cm.doc.mode, state, function (end, style) {
              st.push(end, style);
          }, lineClasses, forceToEnd);
  
          // Run overlays, adjust style array.
          for (var o = 0; o < cm.state.overlays.length; ++o) {
              var overlay = cm.state.overlays[o], i = 1, at = 0;
              runMode(cm, line.text, overlay.mode, true, function (end, style) {
                  var start = i;
                  // Ensure there's a token end at the current position, and that i points at it
                  while (at < end) {
                      var i_end = st[i];
                      if (i_end > end)
                          st.splice(i, 1, end, st[i + 1], i_end);
                      i += 2;
                      at = Math.min(end, i_end);
                  }
                  if (!style) return;
                  if (overlay.opaque) {
                      st.splice(start, i - start, end, "cm-overlay " + style);
                      i = start + 2;
                  } else {
                      for (; start < i; start += 2) {
                          var cur = st[start + 1];
                          st[start + 1] = (cur ? cur + " " : "") + "cm-overlay " + style;
                      }
                  }
              }, lineClasses);
          }
  
          return {styles: st, classes: lineClasses.bgClass || lineClasses.textClass ? lineClasses : null};
      }
  
      function getLineStyles(cm, line, updateFrontier) {
          if (!line.styles || line.styles[0] != cm.state.modeGen) {
              var result = highlightLine(cm, line, line.stateAfter = getStateBefore(cm, lineNo(line)));
              line.styles = result.styles;
              if (result.classes) line.styleClasses = result.classes;
              else if (line.styleClasses) line.styleClasses = null;
              if (updateFrontier === cm.doc.frontier) cm.doc.frontier++;
          }
          return line.styles;
      }
  
      // Lightweight form of highlight -- proceed over this line and
      // update state, but don't save a style array. Used for lines that
      // aren't currently visible.
      function processLine(cm, text, state, startAt) {
          var mode = cm.doc.mode;
          var stream = new StringStream(text, cm.options.tabSize);
          stream.start = stream.pos = startAt || 0;
          if (text == "") callBlankLine(mode, state);
          while (!stream.eol() && stream.pos <= cm.options.maxHighlightLength) {
              readToken(mode, stream, state);
              stream.start = stream.pos;
          }
      }
  
      // Convert a style as returned by a mode (either null, or a string
      // containing one or more styles) to a CSS style. This is cached,
      // and also looks for line-wide styles.
      var styleToClassCache = {}, styleToClassCacheWithMode = {};
  
      function interpretTokenStyle(style, options) {
          if (!style || /^\s*$/.test(style)) return null;
          var cache = options.addModeClass ? styleToClassCacheWithMode : styleToClassCache;
          return cache[style] ||
              (cache[style] = style.replace(/\S+/g, "cm-$&"));
      }
  
      // Render the DOM representation of the text of a line. Also builds
      // up a 'line map', which points at the DOM nodes that represent
      // specific stretches of text, and is used by the measuring code.
      // The returned object contains the DOM node, this map, and
      // information about line-wide styles that were set by the mode.
      function buildLineContent(cm, lineView) {
          // The padding-right forces the element to have a 'border', which
          // is needed on Webkit to be able to get line-level bounding
          // rectangles for it (in measureChar).
          var content = elt("span", null, null, webkit ? "padding-right: .1px" : null);
          var builder = {pre: elt("pre", [content]), content: content, col: 0, pos: 0, cm: cm};
          lineView.measure = {};
  
          // Iterate over the logical lines that make up this visual line.
          for (var i = 0; i <= (lineView.rest ? lineView.rest.length : 0); i++) {
              var line = i ? lineView.rest[i - 1] : lineView.line, order;
              builder.pos = 0;
              builder.addToken = buildToken;
              // Optionally wire in some hacks into the token-rendering
              // algorithm, to deal with browser quirks.
              if ((ie || webkit) && cm.getOption("lineWrapping"))
                  builder.addToken = buildTokenSplitSpaces(builder.addToken);
              if (hasBadBidiRects(cm.display.measure) && (order = getOrder(line)))
                  builder.addToken = buildTokenBadBidi(builder.addToken, order);
              builder.map = [];
              var allowFrontierUpdate = lineView != cm.display.externalMeasured && lineNo(line);
              insertLineContent(line, builder, getLineStyles(cm, line, allowFrontierUpdate));
              if (line.styleClasses) {
                  if (line.styleClasses.bgClass)
                      builder.bgClass = joinClasses(line.styleClasses.bgClass, builder.bgClass || "");
                  if (line.styleClasses.textClass)
                      builder.textClass = joinClasses(line.styleClasses.textClass, builder.textClass || "");
              }
  
              // Ensure at least a single node is present, for measuring.
              if (builder.map.length == 0)
                  builder.map.push(0, 0, builder.content.appendChild(zeroWidthElement(cm.display.measure)));
  
              // Store the map and a cache object for the current logical line
              if (i == 0) {
                  lineView.measure.map = builder.map;
                  lineView.measure.cache = {};
              } else {
                  (lineView.measure.maps || (lineView.measure.maps = [])).push(builder.map);
                  (lineView.measure.caches || (lineView.measure.caches = [])).push({});
              }
          }
  
          // See issue #2901
          if (webkit && /\bcm-tab\b/.test(builder.content.lastChild.className))
              builder.content.className = "cm-tab-wrap-hack";
  
          signal(cm, "renderLine", cm, lineView.line, builder.pre);
          if (builder.pre.className)
              builder.textClass = joinClasses(builder.pre.className, builder.textClass || "");
  
          return builder;
      }
  
      function defaultSpecialCharPlaceholder(ch) {
          var token = elt("span", "\u2022", "cm-invalidchar");
          token.title = "\\u" + ch.charCodeAt(0).toString(16);
          token.setAttribute("aria-label", token.title);
          return token;
      }
  
      // Build up the DOM representation for a single token, and add it to
      // the line map. Takes care to render special characters separately.
      function buildToken(builder, text, style, startStyle, endStyle, title, css) {
          if (!text) return;
          var special = builder.cm.options.specialChars, mustWrap = false;
          if (!special.test(text)) {
              builder.col += text.length;
              var content = document.createTextNode(text);
              builder.map.push(builder.pos, builder.pos + text.length, content);
              if (ie && ie_version < 9) mustWrap = true;
              builder.pos += text.length;
          } else {
              var content = document.createDocumentFragment(), pos = 0;
              while (true) {
                  special.lastIndex = pos;
                  var m = special.exec(text);
                  var skipped = m ? m.index - pos : text.length - pos;
                  if (skipped) {
                      var txt = document.createTextNode(text.slice(pos, pos + skipped));
                      if (ie && ie_version < 9) content.appendChild(elt("span", [txt]));
                      else content.appendChild(txt);
                      builder.map.push(builder.pos, builder.pos + skipped, txt);
                      builder.col += skipped;
                      builder.pos += skipped;
                  }
                  if (!m) break;
                  pos += skipped + 1;
                  if (m[0] == "\t") {
                      var tabSize = builder.cm.options.tabSize, tabWidth = tabSize - builder.col % tabSize;
                      var txt = content.appendChild(elt("span", spaceStr(tabWidth), "cm-tab"));
                      txt.setAttribute("role", "presentation");
                      txt.setAttribute("cm-text", "\t");
                      builder.col += tabWidth;
                  } else {
                      var txt = builder.cm.options.specialCharPlaceholder(m[0]);
                      txt.setAttribute("cm-text", m[0]);
                      if (ie && ie_version < 9) content.appendChild(elt("span", [txt]));
                      else content.appendChild(txt);
                      builder.col += 1;
                  }
                  builder.map.push(builder.pos, builder.pos + 1, txt);
                  builder.pos++;
              }
          }
          if (style || startStyle || endStyle || mustWrap || css) {
              var fullStyle = style || "";
              if (startStyle) fullStyle += startStyle;
              if (endStyle) fullStyle += endStyle;
              var token = elt("span", [content], fullStyle, css);
              if (title) token.title = title;
              return builder.content.appendChild(token);
          }
          builder.content.appendChild(content);
      }
  
      function buildTokenSplitSpaces(inner) {
          function split(old) {
              var out = " ";
              for (var i = 0; i < old.length - 2; ++i) out += i % 2 ? " " : "\u00a0";
              out += " ";
              return out;
          }
  
          return function (builder, text, style, startStyle, endStyle, title) {
              inner(builder, text.replace(/ {3,}/g, split), style, startStyle, endStyle, title);
          };
      }
  
      // Work around nonsense dimensions being reported for stretches of
      // right-to-left text.
      function buildTokenBadBidi(inner, order) {
          return function (builder, text, style, startStyle, endStyle, title) {
              style = style ? style + " cm-force-border" : "cm-force-border";
              var start = builder.pos, end = start + text.length;
              for (; ;) {
                  // Find the part that overlaps with the start of this text
                  for (var i = 0; i < order.length; i++) {
                      var part = order[i];
                      if (part.to > start && part.from <= start) break;
                  }
                  if (part.to >= end) return inner(builder, text, style, startStyle, endStyle, title);
                  inner(builder, text.slice(0, part.to - start), style, startStyle, null, title);
                  startStyle = null;
                  text = text.slice(part.to - start);
                  start = part.to;
              }
          };
      }
  
      function buildCollapsedSpan(builder, size, marker, ignoreWidget) {
          var widget = !ignoreWidget && marker.widgetNode;
          if (widget) builder.map.push(builder.pos, builder.pos + size, widget);
          if (!ignoreWidget && builder.cm.display.input.needsContentAttribute) {
              if (!widget)
                  widget = builder.content.appendChild(document.createElement("span"));
              widget.setAttribute("cm-marker", marker.id);
          }
          if (widget) {
              builder.cm.display.input.setUneditable(widget);
              builder.content.appendChild(widget);
          }
          builder.pos += size;
      }
  
      // Outputs a number of spans to make up a line, taking highlighting
      // and marked text into account.
      function insertLineContent(line, builder, styles) {
          var spans = line.markedSpans, allText = line.text, at = 0;
          if (!spans) {
              for (var i = 1; i < styles.length; i += 2)
                  builder.addToken(builder, allText.slice(at, at = styles[i]), interpretTokenStyle(styles[i + 1], builder.cm.options));
              return;
          }
  
          var len = allText.length, pos = 0, i = 1, text = "", style, css;
          var nextChange = 0, spanStyle, spanEndStyle, spanStartStyle, title, collapsed;
          for (; ;) {
              if (nextChange == pos) { // Update current marker set
                  spanStyle = spanEndStyle = spanStartStyle = title = css = "";
                  collapsed = null;
                  nextChange = Infinity;
                  var foundBookmarks = [];
                  for (var j = 0; j < spans.length; ++j) {
                      var sp = spans[j], m = sp.marker;
                      if (sp.from <= pos && (sp.to == null || sp.to > pos)) {
                          if (sp.to != null && nextChange > sp.to) {
                              nextChange = sp.to;
                              spanEndStyle = "";
                          }
                          if (m.className) spanStyle += " " + m.className;
                          if (m.css) css = m.css;
                          if (m.startStyle && sp.from == pos) spanStartStyle += " " + m.startStyle;
                          if (m.endStyle && sp.to == nextChange) spanEndStyle += " " + m.endStyle;
                          if (m.title && !title) title = m.title;
                          if (m.collapsed && (!collapsed || compareCollapsedMarkers(collapsed.marker, m) < 0))
                              collapsed = sp;
                      } else if (sp.from > pos && nextChange > sp.from) {
                          nextChange = sp.from;
                      }
                      if (m.type == "bookmark" && sp.from == pos && m.widgetNode) foundBookmarks.push(m);
                  }
                  if (collapsed && (collapsed.from || 0) == pos) {
                      buildCollapsedSpan(builder, (collapsed.to == null ? len + 1 : collapsed.to) - pos,
                          collapsed.marker, collapsed.from == null);
                      if (collapsed.to == null) return;
                  }
                  if (!collapsed && foundBookmarks.length) for (var j = 0; j < foundBookmarks.length; ++j)
                      buildCollapsedSpan(builder, 0, foundBookmarks[j]);
              }
              if (pos >= len) break;
  
              var upto = Math.min(len, nextChange);
              while (true) {
                  if (text) {
                      var end = pos + text.length;
                      if (!collapsed) {
                          var tokenText = end > upto ? text.slice(0, upto - pos) : text;
                          builder.addToken(builder, tokenText, style ? style + spanStyle : spanStyle,
                              spanStartStyle, pos + tokenText.length == nextChange ? spanEndStyle : "", title, css);
                      }
                      if (end >= upto) {
                          text = text.slice(upto - pos);
                          pos = upto;
                          break;
                      }
                      pos = end;
                      spanStartStyle = "";
                  }
                  text = allText.slice(at, at = styles[i++]);
                  style = interpretTokenStyle(styles[i++], builder.cm.options);
              }
          }
      }
  
      // DOCUMENT DATA STRUCTURE
  
      // By default, updates that start and end at the beginning of a line
      // are treated specially, in order to make the association of line
      // widgets and marker elements with the text behave more intuitive.
      function isWholeLineUpdate(doc, change) {
          return change.from.ch == 0 && change.to.ch == 0 && lst(change.text) == "" &&
              (!doc.cm || doc.cm.options.wholeLineUpdateBefore);
      }
  
      // Perform a change on the document data structure.
      function updateDoc(doc, change, markedSpans, estimateHeight) {
          function spansFor(n) {
              return markedSpans ? markedSpans[n] : null;
          }
  
          function update(line, text, spans) {
              updateLine(line, text, spans, estimateHeight);
              signalLater(line, "change", line, change);
          }
  
          function linesFor(start, end) {
              for (var i = start, result = []; i < end; ++i)
                  result.push(new Line(text[i], spansFor(i), estimateHeight));
              return result;
          }
  
          var from = change.from, to = change.to, text = change.text;
          var firstLine = getLine(doc, from.line), lastLine = getLine(doc, to.line);
          var lastText = lst(text), lastSpans = spansFor(text.length - 1), nlines = to.line - from.line;
  
          // Adjust the line structure
          if (change.full) {
              doc.insert(0, linesFor(0, text.length));
              doc.remove(text.length, doc.size - text.length);
          } else if (isWholeLineUpdate(doc, change)) {
              // This is a whole-line replace. Treated specially to make
              // sure line objects move the way they are supposed to.
              var added = linesFor(0, text.length - 1);
              update(lastLine, lastLine.text, lastSpans);
              if (nlines) doc.remove(from.line, nlines);
              if (added.length) doc.insert(from.line, added);
          } else if (firstLine == lastLine) {
              if (text.length == 1) {
                  update(firstLine, firstLine.text.slice(0, from.ch) + lastText + firstLine.text.slice(to.ch), lastSpans);
              } else {
                  var added = linesFor(1, text.length - 1);
                  added.push(new Line(lastText + firstLine.text.slice(to.ch), lastSpans, estimateHeight));
                  update(firstLine, firstLine.text.slice(0, from.ch) + text[0], spansFor(0));
                  doc.insert(from.line + 1, added);
              }
          } else if (text.length == 1) {
              update(firstLine, firstLine.text.slice(0, from.ch) + text[0] + lastLine.text.slice(to.ch), spansFor(0));
              doc.remove(from.line + 1, nlines);
          } else {
              update(firstLine, firstLine.text.slice(0, from.ch) + text[0], spansFor(0));
              update(lastLine, lastText + lastLine.text.slice(to.ch), lastSpans);
              var added = linesFor(1, text.length - 1);
              if (nlines > 1) doc.remove(from.line + 1, nlines - 1);
              doc.insert(from.line + 1, added);
          }
  
          signalLater(doc, "change", doc, change);
      }
  
      // The document is represented as a BTree consisting of leaves, with
      // chunk of lines in them, and branches, with up to ten leaves or
      // other branch nodes below them. The top node is always a branch
      // node, and is the document object itself (meaning it has
      // additional methods and properties).
      //
      // All nodes have parent links. The tree is used both to go from
      // line numbers to line objects, and to go from objects to numbers.
      // It also indexes by height, and is used to convert between height
      // and line object, and to find the total height of the document.
      //
      // See also http://marijnhaverbeke.nl/blog/codemirror-line-tree.html
  
      function LeafChunk(lines) {
          this.lines = lines;
          this.parent = null;
          for (var i = 0, height = 0; i < lines.length; ++i) {
              lines[i].parent = this;
              height += lines[i].height;
          }
          this.height = height;
      }
  
      LeafChunk.prototype = {
          chunkSize: function () {
              return this.lines.length;
          },
          // Remove the n lines at offset 'at'.
          removeInner: function (at, n) {
              for (var i = at, e = at + n; i < e; ++i) {
                  var line = this.lines[i];
                  this.height -= line.height;
                  cleanUpLine(line);
                  signalLater(line, "delete");
              }
              this.lines.splice(at, n);
          },
          // Helper used to collapse a small branch into a single leaf.
          collapse: function (lines) {
              lines.push.apply(lines, this.lines);
          },
          // Insert the given array of lines at offset 'at', count them as
          // having the given height.
          insertInner: function (at, lines, height) {
              this.height += height;
              this.lines = this.lines.slice(0, at).concat(lines).concat(this.lines.slice(at));
              for (var i = 0; i < lines.length; ++i) lines[i].parent = this;
          },
          // Used to iterate over a part of the tree.
          iterN: function (at, n, op) {
              for (var e = at + n; at < e; ++at)
                  if (op(this.lines[at])) return true;
          }
      };
  
      function BranchChunk(children) {
          this.children = children;
          var size = 0, height = 0;
          for (var i = 0; i < children.length; ++i) {
              var ch = children[i];
              size += ch.chunkSize();
              height += ch.height;
              ch.parent = this;
          }
          this.size = size;
          this.height = height;
          this.parent = null;
      }
  
      BranchChunk.prototype = {
          chunkSize: function () {
              return this.size;
          },
          removeInner: function (at, n) {
              this.size -= n;
              for (var i = 0; i < this.children.length; ++i) {
                  var child = this.children[i], sz = child.chunkSize();
                  if (at < sz) {
                      var rm = Math.min(n, sz - at), oldHeight = child.height;
                      child.removeInner(at, rm);
                      this.height -= oldHeight - child.height;
                      if (sz == rm) {
                          this.children.splice(i--, 1);
                          child.parent = null;
                      }
                      if ((n -= rm) == 0) break;
                      at = 0;
                  } else at -= sz;
              }
              // If the result is smaller than 25 lines, ensure that it is a
              // single leaf node.
              if (this.size - n < 25 &&
                  (this.children.length > 1 || !(this.children[0] instanceof LeafChunk))) {
                  var lines = [];
                  this.collapse(lines);
                  this.children = [new LeafChunk(lines)];
                  this.children[0].parent = this;
              }
          },
          collapse: function (lines) {
              for (var i = 0; i < this.children.length; ++i) this.children[i].collapse(lines);
          },
          insertInner: function (at, lines, height) {
              this.size += lines.length;
              this.height += height;
              for (var i = 0; i < this.children.length; ++i) {
                  var child = this.children[i], sz = child.chunkSize();
                  if (at <= sz) {
                      child.insertInner(at, lines, height);
                      if (child.lines && child.lines.length > 50) {
                          while (child.lines.length > 50) {
                              var spilled = child.lines.splice(child.lines.length - 25, 25);
                              var newleaf = new LeafChunk(spilled);
                              child.height -= newleaf.height;
                              this.children.splice(i + 1, 0, newleaf);
                              newleaf.parent = this;
                          }
                          this.maybeSpill();
                      }
                      break;
                  }
                  at -= sz;
              }
          },
          // When a node has grown, check whether it should be split.
          maybeSpill: function () {
              if (this.children.length <= 10) return;
              var me = this;
              do {
                  var spilled = me.children.splice(me.children.length - 5, 5);
                  var sibling = new BranchChunk(spilled);
                  if (!me.parent) { // Become the parent node
                      var copy = new BranchChunk(me.children);
                      copy.parent = me;
                      me.children = [copy, sibling];
                      me = copy;
                  } else {
                      me.size -= sibling.size;
                      me.height -= sibling.height;
                      var myIndex = indexOf(me.parent.children, me);
                      me.parent.children.splice(myIndex + 1, 0, sibling);
                  }
                  sibling.parent = me.parent;
              } while (me.children.length > 10);
              me.parent.maybeSpill();
          },
          iterN: function (at, n, op) {
              for (var i = 0; i < this.children.length; ++i) {
                  var child = this.children[i], sz = child.chunkSize();
                  if (at < sz) {
                      var used = Math.min(n, sz - at);
                      if (child.iterN(at, used, op)) return true;
                      if ((n -= used) == 0) break;
                      at = 0;
                  } else at -= sz;
              }
          }
      };
  
      var nextDocId = 0;
      var Doc = CodeMirror.Doc = function (text, mode, firstLine) {
          if (!(this instanceof Doc)) return new Doc(text, mode, firstLine);
          if (firstLine == null) firstLine = 0;
  
          BranchChunk.call(this, [new LeafChunk([new Line("", null)])]);
          this.first = firstLine;
          this.scrollTop = this.scrollLeft = 0;
          this.cantEdit = false;
          this.cleanGeneration = 1;
          this.frontier = firstLine;
          var start = Pos(firstLine, 0);
          this.sel = simpleSelection(start);
          this.history = new History(null);
          this.id = ++nextDocId;
          this.modeOption = mode;
  
          if (typeof text == "string") text = splitLines(text);
          updateDoc(this, {from: start, to: start, text: text});
          setSelection(this, simpleSelection(start), sel_dontScroll);
      };
  
      Doc.prototype = createObj(BranchChunk.prototype, {
          constructor: Doc,
          // Iterate over the document. Supports two forms -- with only one
          // argument, it calls that for each line in the document. With
          // three, it iterates over the range given by the first two (with
          // the second being non-inclusive).
          iter: function (from, to, op) {
              if (op) this.iterN(from - this.first, to - from, op);
              else this.iterN(this.first, this.first + this.size, from);
          },
  
          // Non-public interface for adding and removing lines.
          insert: function (at, lines) {
              var height = 0;
              for (var i = 0; i < lines.length; ++i) height += lines[i].height;
              this.insertInner(at - this.first, lines, height);
          },
          remove: function (at, n) {
              this.removeInner(at - this.first, n);
          },
  
          // From here, the methods are part of the public interface. Most
          // are also available from CodeMirror (editor) instances.
  
          getValue: function (lineSep) {
              var lines = getLines(this, this.first, this.first + this.size);
              if (lineSep === false) return lines;
              return lines.join(lineSep || "\n");
          },
          setValue: docMethodOp(function (code) {
              var top = Pos(this.first, 0), last = this.first + this.size - 1;
              makeChange(this, {
                  from: top, to: Pos(last, getLine(this, last).text.length),
                  text: splitLines(code), origin: "setValue", full: true
              }, true);
              setSelection(this, simpleSelection(top));
          }),
          replaceRange: function (code, from, to, origin) {
              from = clipPos(this, from);
              to = to ? clipPos(this, to) : from;
              replaceRange(this, code, from, to, origin);
          },
          getRange: function (from, to, lineSep) {
              var lines = getBetween(this, clipPos(this, from), clipPos(this, to));
              if (lineSep === false) return lines;
              return lines.join(lineSep || "\n");
          },
  
          getLine: function (line) {
              var l = this.getLineHandle(line);
              return l && l.text;
          },
  
          getLineHandle: function (line) {
              if (isLine(this, line)) return getLine(this, line);
          },
          getLineNumber: function (line) {
              return lineNo(line);
          },
  
          getLineHandleVisualStart: function (line) {
              if (typeof line == "number") line = getLine(this, line);
              return visualLine(line);
          },
  
          lineCount: function () {
              return this.size;
          },
          firstLine: function () {
              return this.first;
          },
          lastLine: function () {
              return this.first + this.size - 1;
          },
  
          clipPos: function (pos) {
              return clipPos(this, pos);
          },
  
          getCursor: function (start) {
              var range = this.sel.primary(), pos;
              if (start == null || start == "head") pos = range.head;
              else if (start == "anchor") pos = range.anchor;
              else if (start == "end" || start == "to" || start === false) pos = range.to();
              else pos = range.from();
              return pos;
          },
          listSelections: function () {
              return this.sel.ranges;
          },
          somethingSelected: function () {
              return this.sel.somethingSelected();
          },
  
          setCursor: docMethodOp(function (line, ch, options) {
              setSimpleSelection(this, clipPos(this, typeof line == "number" ? Pos(line, ch || 0) : line), null, options);
          }),
          setSelection: docMethodOp(function (anchor, head, options) {
              setSimpleSelection(this, clipPos(this, anchor), clipPos(this, head || anchor), options);
          }),
          extendSelection: docMethodOp(function (head, other, options) {
              extendSelection(this, clipPos(this, head), other && clipPos(this, other), options);
          }),
          extendSelections: docMethodOp(function (heads, options) {
              extendSelections(this, clipPosArray(this, heads, options));
          }),
          extendSelectionsBy: docMethodOp(function (f, options) {
              extendSelections(this, map(this.sel.ranges, f), options);
          }),
          setSelections: docMethodOp(function (ranges, primary, options) {
              if (!ranges.length) return;
              for (var i = 0, out = []; i < ranges.length; i++)
                  out[i] = new Range(clipPos(this, ranges[i].anchor),
                      clipPos(this, ranges[i].head));
              if (primary == null) primary = Math.min(ranges.length - 1, this.sel.primIndex);
              setSelection(this, normalizeSelection(out, primary), options);
          }),
          addSelection: docMethodOp(function (anchor, head, options) {
              var ranges = this.sel.ranges.slice(0);
              ranges.push(new Range(clipPos(this, anchor), clipPos(this, head || anchor)));
              setSelection(this, normalizeSelection(ranges, ranges.length - 1), options);
          }),
  
          getSelection: function (lineSep) {
              var ranges = this.sel.ranges, lines;
              for (var i = 0; i < ranges.length; i++) {
                  var sel = getBetween(this, ranges[i].from(), ranges[i].to());
                  lines = lines ? lines.concat(sel) : sel;
              }
              if (lineSep === false) return lines;
              else return lines.join(lineSep || "\n");
          },
          getSelections: function (lineSep) {
              var parts = [], ranges = this.sel.ranges;
              for (var i = 0; i < ranges.length; i++) {
                  var sel = getBetween(this, ranges[i].from(), ranges[i].to());
                  if (lineSep !== false) sel = sel.join(lineSep || "\n");
                  parts[i] = sel;
              }
              return parts;
          },
          replaceSelection: function (code, collapse, origin) {
              var dup = [];
              for (var i = 0; i < this.sel.ranges.length; i++)
                  dup[i] = code;
              this.replaceSelections(dup, collapse, origin || "+input");
          },
          replaceSelections: docMethodOp(function (code, collapse, origin) {
              var changes = [], sel = this.sel;
              for (var i = 0; i < sel.ranges.length; i++) {
                  var range = sel.ranges[i];
                  changes[i] = {from: range.from(), to: range.to(), text: splitLines(code[i]), origin: origin};
              }
              var newSel = collapse && collapse != "end" && computeReplacedSel(this, changes, collapse);
              for (var i = changes.length - 1; i >= 0; i--)
                  makeChange(this, changes[i]);
              if (newSel) setSelectionReplaceHistory(this, newSel);
              else if (this.cm) ensureCursorVisible(this.cm);
          }),
          undo: docMethodOp(function () {
              makeChangeFromHistory(this, "undo");
          }),
          redo: docMethodOp(function () {
              makeChangeFromHistory(this, "redo");
          }),
          undoSelection: docMethodOp(function () {
              makeChangeFromHistory(this, "undo", true);
          }),
          redoSelection: docMethodOp(function () {
              makeChangeFromHistory(this, "redo", true);
          }),
  
          setExtending: function (val) {
              this.extend = val;
          },
          getExtending: function () {
              return this.extend;
          },
  
          historySize: function () {
              var hist = this.history, done = 0, undone = 0;
              for (var i = 0; i < hist.done.length; i++) if (!hist.done[i].ranges) ++done;
              for (var i = 0; i < hist.undone.length; i++) if (!hist.undone[i].ranges) ++undone;
              return {undo: done, redo: undone};
          },
          clearHistory: function () {
              this.history = new History(this.history.maxGeneration);
          },
  
          markClean: function () {
              this.cleanGeneration = this.changeGeneration(true);
          },
          changeGeneration: function (forceSplit) {
              if (forceSplit)
                  this.history.lastOp = this.history.lastSelOp = this.history.lastOrigin = null;
              return this.history.generation;
          },
          isClean: function (gen) {
              return this.history.generation == (gen || this.cleanGeneration);
          },
  
          getHistory: function () {
              return {
                  done: copyHistoryArray(this.history.done),
                  undone: copyHistoryArray(this.history.undone)
              };
          },
          setHistory: function (histData) {
              var hist = this.history = new History(this.history.maxGeneration);
              hist.done = copyHistoryArray(histData.done.slice(0), null, true);
              hist.undone = copyHistoryArray(histData.undone.slice(0), null, true);
          },
  
          addLineClass: docMethodOp(function (handle, where, cls) {
              return changeLine(this, handle, where == "gutter" ? "gutter" : "class", function (line) {
                  var prop = where == "text" ? "textClass"
                      : where == "background" ? "bgClass"
                          : where == "gutter" ? "gutterClass" : "wrapClass";
                  if (!line[prop]) line[prop] = cls;
                  else if (classTest(cls).test(line[prop])) return false;
                  else line[prop] += " " + cls;
                  return true;
              });
          }),
          removeLineClass: docMethodOp(function (handle, where, cls) {
              return changeLine(this, handle, where == "gutter" ? "gutter" : "class", function (line) {
                  var prop = where == "text" ? "textClass"
                      : where == "background" ? "bgClass"
                          : where == "gutter" ? "gutterClass" : "wrapClass";
                  var cur = line[prop];
                  if (!cur) return false;
                  else if (cls == null) line[prop] = null;
                  else {
                      var found = cur.match(classTest(cls));
                      if (!found) return false;
                      var end = found.index + found[0].length;
                      line[prop] = cur.slice(0, found.index) + (!found.index || end == cur.length ? "" : " ") + cur.slice(end) || null;
                  }
                  return true;
              });
          }),
  
          markText: function (from, to, options) {
              return markText(this, clipPos(this, from), clipPos(this, to), options, "range");
          },
          setBookmark: function (pos, options) {
              var realOpts = {
                  replacedWith: options && (options.nodeType == null ? options.widget : options),
                  insertLeft: options && options.insertLeft,
                  clearWhenEmpty: false, shared: options && options.shared
              };
              pos = clipPos(this, pos);
              return markText(this, pos, pos, realOpts, "bookmark");
          },
          findMarksAt: function (pos) {
              pos = clipPos(this, pos);
              var markers = [], spans = getLine(this, pos.line).markedSpans;
              if (spans) for (var i = 0; i < spans.length; ++i) {
                  var span = spans[i];
                  if ((span.from == null || span.from <= pos.ch) &&
                      (span.to == null || span.to >= pos.ch))
                      markers.push(span.marker.parent || span.marker);
              }
              return markers;
          },
          findMarks: function (from, to, filter) {
              from = clipPos(this, from);
              to = clipPos(this, to);
              var found = [], lineNo = from.line;
              this.iter(from.line, to.line + 1, function (line) {
                  var spans = line.markedSpans;
                  if (spans) for (var i = 0; i < spans.length; i++) {
                      var span = spans[i];
                      if (!(lineNo == from.line && from.ch > span.to ||
                          span.from == null && lineNo != from.line ||
                          lineNo == to.line && span.from > to.ch) &&
                          (!filter || filter(span.marker)))
                          found.push(span.marker.parent || span.marker);
                  }
                  ++lineNo;
              });
              return found;
          },
          getAllMarks: function () {
              var markers = [];
              this.iter(function (line) {
                  var sps = line.markedSpans;
                  if (sps) for (var i = 0; i < sps.length; ++i)
                      if (sps[i].from != null) markers.push(sps[i].marker);
              });
              return markers;
          },
  
          posFromIndex: function (off) {
              var ch, lineNo = this.first;
              this.iter(function (line) {
                  var sz = line.text.length + 1;
                  if (sz > off) {
                      ch = off;
                      return true;
                  }
                  off -= sz;
                  ++lineNo;
              });
              return clipPos(this, Pos(lineNo, ch));
          },
          indexFromPos: function (coords) {
              coords = clipPos(this, coords);
              var index = coords.ch;
              if (coords.line < this.first || coords.ch < 0) return 0;
              this.iter(this.first, coords.line, function (line) {
                  index += line.text.length + 1;
              });
              return index;
          },
  
          copy: function (copyHistory) {
              var doc = new Doc(getLines(this, this.first, this.first + this.size), this.modeOption, this.first);
              doc.scrollTop = this.scrollTop;
              doc.scrollLeft = this.scrollLeft;
              doc.sel = this.sel;
              doc.extend = false;
              if (copyHistory) {
                  doc.history.undoDepth = this.history.undoDepth;
                  doc.setHistory(this.getHistory());
              }
              return doc;
          },
  
          linkedDoc: function (options) {
              if (!options) options = {};
              var from = this.first, to = this.first + this.size;
              if (options.from != null && options.from > from) from = options.from;
              if (options.to != null && options.to < to) to = options.to;
              var copy = new Doc(getLines(this, from, to), options.mode || this.modeOption, from);
              if (options.sharedHist) copy.history = this.history;
              (this.linked || (this.linked = [])).push({doc: copy, sharedHist: options.sharedHist});
              copy.linked = [{doc: this, isParent: true, sharedHist: options.sharedHist}];
              copySharedMarkers(copy, findSharedMarkers(this));
              return copy;
          },
          unlinkDoc: function (other) {
              if (other instanceof CodeMirror) other = other.doc;
              if (this.linked) for (var i = 0; i < this.linked.length; ++i) {
                  var link = this.linked[i];
                  if (link.doc != other) continue;
                  this.linked.splice(i, 1);
                  other.unlinkDoc(this);
                  detachSharedMarkers(findSharedMarkers(this));
                  break;
              }
              // If the histories were shared, split them again
              if (other.history == this.history) {
                  var splitIds = [other.id];
                  linkedDocs(other, function (doc) {
                      splitIds.push(doc.id);
                  }, true);
                  other.history = new History(null);
                  other.history.done = copyHistoryArray(this.history.done, splitIds);
                  other.history.undone = copyHistoryArray(this.history.undone, splitIds);
              }
          },
          iterLinkedDocs: function (f) {
              linkedDocs(this, f);
          },
  
          getMode: function () {
              return this.mode;
          },
          getEditor: function () {
              return this.cm;
          }
      });
  
      // Public alias.
      Doc.prototype.eachLine = Doc.prototype.iter;
  
      // Set up methods on CodeMirror's prototype to redirect to the editor's document.
      var dontDelegate = "iter insert remove copy getEditor".split(" ");
      for (var prop in Doc.prototype) if (Doc.prototype.hasOwnProperty(prop) && indexOf(dontDelegate, prop) < 0)
          CodeMirror.prototype[prop] = (function (method) {
              return function () {
                  return method.apply(this.doc, arguments);
              };
          })(Doc.prototype[prop]);
  
      eventMixin(Doc);
  
      // Call f for all linked documents.
      function linkedDocs(doc, f, sharedHistOnly) {
          function propagate(doc, skip, sharedHist) {
              if (doc.linked) for (var i = 0; i < doc.linked.length; ++i) {
                  var rel = doc.linked[i];
                  if (rel.doc == skip) continue;
                  var shared = sharedHist && rel.sharedHist;
                  if (sharedHistOnly && !shared) continue;
                  f(rel.doc, shared);
                  propagate(rel.doc, doc, shared);
              }
          }
  
          propagate(doc, null, true);
      }
  
      // Attach a document to an editor.
      function attachDoc(cm, doc) {
          if (doc.cm) throw new Error("This document is already in use.");
          cm.doc = doc;
          doc.cm = cm;
          estimateLineHeights(cm);
          loadMode(cm);
          if (!cm.options.lineWrapping) findMaxLine(cm);
          cm.options.mode = doc.modeOption;
          regChange(cm);
      }
  
      // LINE UTILITIES
  
      // Find the line object corresponding to the given line number.
      function getLine(doc, n) {
          n -= doc.first;
          if (n < 0 || n >= doc.size) throw new Error("There is no line " + (n + doc.first) + " in the document.");
          for (var chunk = doc; !chunk.lines;) {
              for (var i = 0; ; ++i) {
                  var child = chunk.children[i], sz = child.chunkSize();
                  if (n < sz) {
                      chunk = child;
                      break;
                  }
                  n -= sz;
              }
          }
          return chunk.lines[n];
      }
  
      // Get the part of a document between two positions, as an array of
      // strings.
      function getBetween(doc, start, end) {
          var out = [], n = start.line;
          doc.iter(start.line, end.line + 1, function (line) {
              var text = line.text;
              if (n == end.line) text = text.slice(0, end.ch);
              if (n == start.line) text = text.slice(start.ch);
              out.push(text);
              ++n;
          });
          return out;
      }
  
      // Get the lines between from and to, as array of strings.
      function getLines(doc, from, to) {
          var out = [];
          doc.iter(from, to, function (line) {
              out.push(line.text);
          });
          return out;
      }
  
      // Update the height of a line, propagating the height change
      // upwards to parent nodes.
      function updateLineHeight(line, height) {
          var diff = height - line.height;
          if (diff) for (var n = line; n; n = n.parent) n.height += diff;
      }
  
      // Given a line object, find its line number by walking up through
      // its parent links.
      function lineNo(line) {
          if (line.parent == null) return null;
          var cur = line.parent, no = indexOf(cur.lines, line);
          for (var chunk = cur.parent; chunk; cur = chunk, chunk = chunk.parent) {
              for (var i = 0; ; ++i) {
                  if (chunk.children[i] == cur) break;
                  no += chunk.children[i].chunkSize();
              }
          }
          return no + cur.first;
      }
  
      // Find the line at the given vertical position, using the height
      // information in the document tree.
      function lineAtHeight(chunk, h) {
          var n = chunk.first;
          outer: do {
              for (var i = 0; i < chunk.children.length; ++i) {
                  var child = chunk.children[i], ch = child.height;
                  if (h < ch) {
                      chunk = child;
                      continue outer;
                  }
                  h -= ch;
                  n += child.chunkSize();
              }
              return n;
          } while (!chunk.lines);
          for (var i = 0; i < chunk.lines.length; ++i) {
              var line = chunk.lines[i], lh = line.height;
              if (h < lh) break;
              h -= lh;
          }
          return n + i;
      }
  
  
      // Find the height above the given line.
      function heightAtLine(lineObj) {
          lineObj = visualLine(lineObj);
  
          var h = 0, chunk = lineObj.parent;
          for (var i = 0; i < chunk.lines.length; ++i) {
              var line = chunk.lines[i];
              if (line == lineObj) break;
              else h += line.height;
          }
          for (var p = chunk.parent; p; chunk = p, p = chunk.parent) {
              for (var i = 0; i < p.children.length; ++i) {
                  var cur = p.children[i];
                  if (cur == chunk) break;
                  else h += cur.height;
              }
          }
          return h;
      }
  
      // Get the bidi ordering for the given line (and cache it). Returns
      // false for lines that are fully left-to-right, and an array of
      // BidiSpan objects otherwise.
      function getOrder(line) {
          var order = line.order;
          if (order == null) order = line.order = bidiOrdering(line.text);
          return order;
      }
  
      // HISTORY
  
      function History(startGen) {
          // Arrays of change events and selections. Doing something adds an
          // event to done and clears undo. Undoing moves events from done
          // to undone, redoing moves them in the other direction.
          this.done = [];
          this.undone = [];
          this.undoDepth = Infinity;
          // Used to track when changes can be merged into a single undo
          // event
          this.lastModTime = this.lastSelTime = 0;
          this.lastOp = this.lastSelOp = null;
          this.lastOrigin = this.lastSelOrigin = null;
          // Used by the isClean() method
          this.generation = this.maxGeneration = startGen || 1;
      }
  
      // Create a history change event from an updateDoc-style change
      // object.
      function historyChangeFromChange(doc, change) {
          var histChange = {
              from: copyPos(change.from),
              to: changeEnd(change),
              text: getBetween(doc, change.from, change.to)
          };
          attachLocalSpans(doc, histChange, change.from.line, change.to.line + 1);
          linkedDocs(doc, function (doc) {
              attachLocalSpans(doc, histChange, change.from.line, change.to.line + 1);
          }, true);
          return histChange;
      }
  
      // Pop all selection events off the end of a history array. Stop at
      // a change event.
      function clearSelectionEvents(array) {
          while (array.length) {
              var last = lst(array);
              if (last.ranges) array.pop();
              else break;
          }
      }
  
      // Find the top change event in the history. Pop off selection
      // events that are in the way.
      function lastChangeEvent(hist, force) {
          if (force) {
              clearSelectionEvents(hist.done);
              return lst(hist.done);
          } else if (hist.done.length && !lst(hist.done).ranges) {
              return lst(hist.done);
          } else if (hist.done.length > 1 && !hist.done[hist.done.length - 2].ranges) {
              hist.done.pop();
              return lst(hist.done);
          }
      }
  
      // Register a change in the history. Merges changes that are within
      // a single operation, ore are close together with an origin that
      // allows merging (starting with "+") into a single event.
      function addChangeToHistory(doc, change, selAfter, opId) {
          var hist = doc.history;
          hist.undone.length = 0;
          var time = +new Date, cur;
  
          if ((hist.lastOp == opId ||
              hist.lastOrigin == change.origin && change.origin &&
              ((change.origin.charAt(0) == "+" && doc.cm && hist.lastModTime > time - doc.cm.options.historyEventDelay) ||
              change.origin.charAt(0) == "*")) &&
              (cur = lastChangeEvent(hist, hist.lastOp == opId))) {
              // Merge this change into the last event
              var last = lst(cur.changes);
              if (cmp(change.from, change.to) == 0 && cmp(change.from, last.to) == 0) {
                  // Optimized case for simple insertion -- don't want to add
                  // new changesets for every character typed
                  last.to = changeEnd(change);
              } else {
                  // Add new sub-event
                  cur.changes.push(historyChangeFromChange(doc, change));
              }
          } else {
              // Can not be merged, start a new event.
              var before = lst(hist.done);
              if (!before || !before.ranges)
                  pushSelectionToHistory(doc.sel, hist.done);
              cur = {
                  changes: [historyChangeFromChange(doc, change)],
                  generation: hist.generation
              };
              hist.done.push(cur);
              while (hist.done.length > hist.undoDepth) {
                  hist.done.shift();
                  if (!hist.done[0].ranges) hist.done.shift();
              }
          }
          hist.done.push(selAfter);
          hist.generation = ++hist.maxGeneration;
          hist.lastModTime = hist.lastSelTime = time;
          hist.lastOp = hist.lastSelOp = opId;
          hist.lastOrigin = hist.lastSelOrigin = change.origin;
  
          if (!last) signal(doc, "historyAdded");
      }
  
      function selectionEventCanBeMerged(doc, origin, prev, sel) {
          var ch = origin.charAt(0);
          return ch == "*" ||
              ch == "+" &&
              prev.ranges.length == sel.ranges.length &&
              prev.somethingSelected() == sel.somethingSelected() &&
              new Date - doc.history.lastSelTime <= (doc.cm ? doc.cm.options.historyEventDelay : 500);
      }
  
      // Called whenever the selection changes, sets the new selection as
      // the pending selection in the history, and pushes the old pending
      // selection into the 'done' array when it was significantly
      // different (in number of selected ranges, emptiness, or time).
      function addSelectionToHistory(doc, sel, opId, options) {
          var hist = doc.history, origin = options && options.origin;
  
          // A new event is started when the previous origin does not match
          // the current, or the origins don't allow matching. Origins
          // starting with * are always merged, those starting with + are
          // merged when similar and close together in time.
          if (opId == hist.lastSelOp ||
              (origin && hist.lastSelOrigin == origin &&
              (hist.lastModTime == hist.lastSelTime && hist.lastOrigin == origin ||
              selectionEventCanBeMerged(doc, origin, lst(hist.done), sel))))
              hist.done[hist.done.length - 1] = sel;
          else
              pushSelectionToHistory(sel, hist.done);
  
          hist.lastSelTime = +new Date;
          hist.lastSelOrigin = origin;
          hist.lastSelOp = opId;
          if (options && options.clearRedo !== false)
              clearSelectionEvents(hist.undone);
      }
  
      function pushSelectionToHistory(sel, dest) {
          var top = lst(dest);
          if (!(top && top.ranges && top.equals(sel)))
              dest.push(sel);
      }
  
      // Used to store marked span information in the history.
      function attachLocalSpans(doc, change, from, to) {
          var existing = change["spans_" + doc.id], n = 0;
          doc.iter(Math.max(doc.first, from), Math.min(doc.first + doc.size, to), function (line) {
              if (line.markedSpans)
                  (existing || (existing = change["spans_" + doc.id] = {}))[n] = line.markedSpans;
              ++n;
          });
      }
  
      // When un/re-doing restores text containing marked spans, those
      // that have been explicitly cleared should not be restored.
      function removeClearedSpans(spans) {
          if (!spans) return null;
          for (var i = 0, out; i < spans.length; ++i) {
              if (spans[i].marker.explicitlyCleared) {
                  if (!out) out = spans.slice(0, i);
              }
              else if (out) out.push(spans[i]);
          }
          return !out ? spans : out.length ? out : null;
      }
  
      // Retrieve and filter the old marked spans stored in a change event.
      function getOldSpans(doc, change) {
          var found = change["spans_" + doc.id];
          if (!found) return null;
          for (var i = 0, nw = []; i < change.text.length; ++i)
              nw.push(removeClearedSpans(found[i]));
          return nw;
      }
  
      // Used both to provide a JSON-safe object in .getHistory, and, when
      // detaching a document, to split the history in two
      function copyHistoryArray(events, newGroup, instantiateSel) {
          for (var i = 0, copy = []; i < events.length; ++i) {
              var event = events[i];
              if (event.ranges) {
                  copy.push(instantiateSel ? Selection.prototype.deepCopy.call(event) : event);
                  continue;
              }
              var changes = event.changes, newChanges = [];
              copy.push({changes: newChanges});
              for (var j = 0; j < changes.length; ++j) {
                  var change = changes[j], m;
                  newChanges.push({from: change.from, to: change.to, text: change.text});
                  if (newGroup) for (var prop in change) if (m = prop.match(/^spans_(\d+)$/)) {
                      if (indexOf(newGroup, Number(m[1])) > -1) {
                          lst(newChanges)[prop] = change[prop];
                          delete change[prop];
                      }
                  }
              }
          }
          return copy;
      }
  
      // Rebasing/resetting history to deal with externally-sourced changes
  
      function rebaseHistSelSingle(pos, from, to, diff) {
          if (to < pos.line) {
              pos.line += diff;
          } else if (from < pos.line) {
              pos.line = from;
              pos.ch = 0;
          }
      }
  
      // Tries to rebase an array of history events given a change in the
      // document. If the change touches the same lines as the event, the
      // event, and everything 'behind' it, is discarded. If the change is
      // before the event, the event's positions are updated. Uses a
      // copy-on-write scheme for the positions, to avoid having to
      // reallocate them all on every rebase, but also avoid problems with
      // shared position objects being unsafely updated.
      function rebaseHistArray(array, from, to, diff) {
          for (var i = 0; i < array.length; ++i) {
              var sub = array[i], ok = true;
              if (sub.ranges) {
                  if (!sub.copied) {
                      sub = array[i] = sub.deepCopy();
                      sub.copied = true;
                  }
                  for (var j = 0; j < sub.ranges.length; j++) {
                      rebaseHistSelSingle(sub.ranges[j].anchor, from, to, diff);
                      rebaseHistSelSingle(sub.ranges[j].head, from, to, diff);
                  }
                  continue;
              }
              for (var j = 0; j < sub.changes.length; ++j) {
                  var cur = sub.changes[j];
                  if (to < cur.from.line) {
                      cur.from = Pos(cur.from.line + diff, cur.from.ch);
                      cur.to = Pos(cur.to.line + diff, cur.to.ch);
                  } else if (from <= cur.to.line) {
                      ok = false;
                      break;
                  }
              }
              if (!ok) {
                  array.splice(0, i + 1);
                  i = 0;
              }
          }
      }
  
      function rebaseHist(hist, change) {
          var from = change.from.line, to = change.to.line, diff = change.text.length - (to - from) - 1;
          rebaseHistArray(hist.done, from, to, diff);
          rebaseHistArray(hist.undone, from, to, diff);
      }
  
      // EVENT UTILITIES
  
      // Due to the fact that we still support jurassic IE versions, some
      // compatibility wrappers are needed.
  
      var e_preventDefault = CodeMirror.e_preventDefault = function (e) {
          if (e.preventDefault) e.preventDefault();
          else e.returnValue = false;
      };
      var e_stopPropagation = CodeMirror.e_stopPropagation = function (e) {
          if (e.stopPropagation) e.stopPropagation();
          else e.cancelBubble = true;
      };
  
      function e_defaultPrevented(e) {
          return e.defaultPrevented != null ? e.defaultPrevented : e.returnValue == false;
      }
  
      var e_stop = CodeMirror.e_stop = function (e) {
          e_preventDefault(e);
          e_stopPropagation(e);
      };
  
      function e_target(e) {
          return e.target || e.srcElement;
      }
  
      function e_button(e) {
          var b = e.which;
          if (b == null) {
              if (e.button & 1) b = 1;
              else if (e.button & 2) b = 3;
              else if (e.button & 4) b = 2;
          }
          if (mac && e.ctrlKey && b == 1) b = 3;
          return b;
      }
  
      // EVENT HANDLING
  
      // Lightweight event framework. on/off also work on DOM nodes,
      // registering native DOM handlers.
  
      var on = CodeMirror.on = function (emitter, type, f) {
          if (emitter.addEventListener)
              emitter.addEventListener(type, f, false);
          else if (emitter.attachEvent)
              emitter.attachEvent("on" + type, f);
          else {
              var map = emitter._handlers || (emitter._handlers = {});
              var arr = map[type] || (map[type] = []);
              arr.push(f);
          }
      };
  
      var off = CodeMirror.off = function (emitter, type, f) {
          if (emitter.removeEventListener)
              emitter.removeEventListener(type, f, false);
          else if (emitter.detachEvent)
              emitter.detachEvent("on" + type, f);
          else {
              var arr = emitter._handlers && emitter._handlers[type];
              if (!arr) return;
              for (var i = 0; i < arr.length; ++i)
                  if (arr[i] == f) {
                      arr.splice(i, 1);
                      break;
                  }
          }
      };
  
      var signal = CodeMirror.signal = function (emitter, type /*, values...*/) {
          var arr = emitter._handlers && emitter._handlers[type];
          if (!arr) return;
          var args = Array.prototype.slice.call(arguments, 2);
          for (var i = 0; i < arr.length; ++i) arr[i].apply(null, args);
      };
  
      var orphanDelayedCallbacks = null;
  
      // Often, we want to signal events at a point where we are in the
      // middle of some work, but don't want the handler to start calling
      // other methods on the editor, which might be in an inconsistent
      // state or simply not expect any other events to happen.
      // signalLater looks whether there are any handlers, and schedules
      // them to be executed when the last operation ends, or, if no
      // operation is active, when a timeout fires.
      function signalLater(emitter, type /*, values...*/) {
          var arr = emitter._handlers && emitter._handlers[type];
          if (!arr) return;
          var args = Array.prototype.slice.call(arguments, 2), list;
          if (operationGroup) {
              list = operationGroup.delayedCallbacks;
          } else if (orphanDelayedCallbacks) {
              list = orphanDelayedCallbacks;
          } else {
              list = orphanDelayedCallbacks = [];
              setTimeout(fireOrphanDelayed, 0);
          }
          function bnd(f) {
              return function () {
                  f.apply(null, args);
              };
          };
          for (var i = 0; i < arr.length; ++i)
              list.push(bnd(arr[i]));
      }
  
      function fireOrphanDelayed() {
          var delayed = orphanDelayedCallbacks;
          orphanDelayedCallbacks = null;
          for (var i = 0; i < delayed.length; ++i) delayed[i]();
      }
  
      // The DOM events that CodeMirror handles can be overridden by
      // registering a (non-DOM) handler on the editor for the event name,
      // and preventDefault-ing the event in that handler.
      function signalDOMEvent(cm, e, override) {
          if (typeof e == "string")
              e = {
                  type: e, preventDefault: function () {
                      this.defaultPrevented = true;
                  }
              };
          signal(cm, override || e.type, cm, e);
          return e_defaultPrevented(e) || e.codemirrorIgnore;
      }
  
      function signalCursorActivity(cm) {
          var arr = cm._handlers && cm._handlers.cursorActivity;
          if (!arr) return;
          var set = cm.curOp.cursorActivityHandlers || (cm.curOp.cursorActivityHandlers = []);
          for (var i = 0; i < arr.length; ++i) if (indexOf(set, arr[i]) == -1)
              set.push(arr[i]);
      }
  
      function hasHandler(emitter, type) {
          var arr = emitter._handlers && emitter._handlers[type];
          return arr && arr.length > 0;
      }
  
      // Add on and off methods to a constructor's prototype, to make
      // registering events on such objects more convenient.
      function eventMixin(ctor) {
          ctor.prototype.on = function (type, f) {
              on(this, type, f);
          };
          ctor.prototype.off = function (type, f) {
              off(this, type, f);
          };
      }
  
      // MISC UTILITIES
  
      // Number of pixels added to scroller and sizer to hide scrollbar
      var scrollerGap = 30;
  
      // Returned or thrown by various protocols to signal 'I'm not
      // handling this'.
      var Pass = CodeMirror.Pass = {
          toString: function () {
              return "CodeMirror.Pass";
          }
      };
  
      // Reused option objects for setSelection & friends
      var sel_dontScroll = {scroll: false}, sel_mouse = {origin: "*mouse"}, sel_move = {origin: "+move"};
  
      function Delayed() {
          this.id = null;
      }
  
      Delayed.prototype.set = function (ms, f) {
          clearTimeout(this.id);
          this.id = setTimeout(f, ms);
      };
  
      // Counts the column offset in a string, taking tabs into account.
      // Used mostly to find indentation.
      var countColumn = CodeMirror.countColumn = function (string, end, tabSize, startIndex, startValue) {
          if (end == null) {
              end = string.search(/[^\s\u00a0]/);
              if (end == -1) end = string.length;
          }
          for (var i = startIndex || 0, n = startValue || 0; ;) {
              var nextTab = string.indexOf("\t", i);
              if (nextTab < 0 || nextTab >= end)
                  return n + (end - i);
              n += nextTab - i;
              n += tabSize - (n % tabSize);
              i = nextTab + 1;
          }
      };
  
      // The inverse of countColumn -- find the offset that corresponds to
      // a particular column.
      function findColumn(string, goal, tabSize) {
          for (var pos = 0, col = 0; ;) {
              var nextTab = string.indexOf("\t", pos);
              if (nextTab == -1) nextTab = string.length;
              var skipped = nextTab - pos;
              if (nextTab == string.length || col + skipped >= goal)
                  return pos + Math.min(skipped, goal - col);
              col += nextTab - pos;
              col += tabSize - (col % tabSize);
              pos = nextTab + 1;
              if (col >= goal) return pos;
          }
      }
  
      var spaceStrs = [""];
  
      function spaceStr(n) {
          while (spaceStrs.length <= n)
              spaceStrs.push(lst(spaceStrs) + " ");
          return spaceStrs[n];
      }
  
      function lst(arr) {
          return arr[arr.length - 1];
      }
  
      var selectInput = function (node) {
          node.select();
      };
      if (ios) // Mobile Safari apparently has a bug where select() is broken.
          selectInput = function (node) {
              node.selectionStart = 0;
              node.selectionEnd = node.value.length;
          };
      else if (ie) // Suppress mysterious IE10 errors
          selectInput = function (node) {
              try {
                  node.select();
              } catch (_e) {
              }
          };
  
      function indexOf(array, elt) {
          for (var i = 0; i < array.length; ++i)
              if (array[i] == elt) return i;
          return -1;
      }
  
      function map(array, f) {
          var out = [];
          for (var i = 0; i < array.length; i++) out[i] = f(array[i], i);
          return out;
      }
  
      function nothing() {
      }
  
      function createObj(base, props) {
          var inst;
          if (Object.create) {
              inst = Object.create(base);
          } else {
              nothing.prototype = base;
              inst = new nothing();
          }
          if (props) copyObj(props, inst);
          return inst;
      };
  
      function copyObj(obj, target, overwrite) {
          if (!target) target = {};
          for (var prop in obj)
              if (obj.hasOwnProperty(prop) && (overwrite !== false || !target.hasOwnProperty(prop)))
                  target[prop] = obj[prop];
          return target;
      }
  
      function bind(f) {
          var args = Array.prototype.slice.call(arguments, 1);
          return function () {
              return f.apply(null, args);
          };
      }
  
      var nonASCIISingleCaseWordChar = /[\u00df\u0590-\u05f4\u0600-\u06ff\u3040-\u309f\u30a0-\u30ff\u3400-\u4db5\u4e00-\u9fcc\uac00-\ud7af]/;
      var isWordCharBasic = CodeMirror.isWordChar = function (ch) {
          return /\w/.test(ch) || ch > "\x80" &&
              (ch.toUpperCase() != ch.toLowerCase() || nonASCIISingleCaseWordChar.test(ch));
      };
  
      function isWordChar(ch, helper) {
          if (!helper) return isWordCharBasic(ch);
          if (helper.source.indexOf("\\w") > -1 && isWordCharBasic(ch)) return true;
          return helper.test(ch);
      }
  
      function isEmpty(obj) {
          for (var n in obj) if (obj.hasOwnProperty(n) && obj[n]) return false;
          return true;
      }
  
      // Extending unicode characters. A series of a non-extending char +
      // any number of extending chars is treated as a single unit as far
      // as editing and measuring is concerned. This is not fully correct,
      // since some scripts/fonts/browsers also treat other configurations
      // of code points as a group.
      var extendingChars = /[\u0300-\u036f\u0483-\u0489\u0591-\u05bd\u05bf\u05c1\u05c2\u05c4\u05c5\u05c7\u0610-\u061a\u064b-\u065e\u0670\u06d6-\u06dc\u06de-\u06e4\u06e7\u06e8\u06ea-\u06ed\u0711\u0730-\u074a\u07a6-\u07b0\u07eb-\u07f3\u0816-\u0819\u081b-\u0823\u0825-\u0827\u0829-\u082d\u0900-\u0902\u093c\u0941-\u0948\u094d\u0951-\u0955\u0962\u0963\u0981\u09bc\u09be\u09c1-\u09c4\u09cd\u09d7\u09e2\u09e3\u0a01\u0a02\u0a3c\u0a41\u0a42\u0a47\u0a48\u0a4b-\u0a4d\u0a51\u0a70\u0a71\u0a75\u0a81\u0a82\u0abc\u0ac1-\u0ac5\u0ac7\u0ac8\u0acd\u0ae2\u0ae3\u0b01\u0b3c\u0b3e\u0b3f\u0b41-\u0b44\u0b4d\u0b56\u0b57\u0b62\u0b63\u0b82\u0bbe\u0bc0\u0bcd\u0bd7\u0c3e-\u0c40\u0c46-\u0c48\u0c4a-\u0c4d\u0c55\u0c56\u0c62\u0c63\u0cbc\u0cbf\u0cc2\u0cc6\u0ccc\u0ccd\u0cd5\u0cd6\u0ce2\u0ce3\u0d3e\u0d41-\u0d44\u0d4d\u0d57\u0d62\u0d63\u0dca\u0dcf\u0dd2-\u0dd4\u0dd6\u0ddf\u0e31\u0e34-\u0e3a\u0e47-\u0e4e\u0eb1\u0eb4-\u0eb9\u0ebb\u0ebc\u0ec8-\u0ecd\u0f18\u0f19\u0f35\u0f37\u0f39\u0f71-\u0f7e\u0f80-\u0f84\u0f86\u0f87\u0f90-\u0f97\u0f99-\u0fbc\u0fc6\u102d-\u1030\u1032-\u1037\u1039\u103a\u103d\u103e\u1058\u1059\u105e-\u1060\u1071-\u1074\u1082\u1085\u1086\u108d\u109d\u135f\u1712-\u1714\u1732-\u1734\u1752\u1753\u1772\u1773\u17b7-\u17bd\u17c6\u17c9-\u17d3\u17dd\u180b-\u180d\u18a9\u1920-\u1922\u1927\u1928\u1932\u1939-\u193b\u1a17\u1a18\u1a56\u1a58-\u1a5e\u1a60\u1a62\u1a65-\u1a6c\u1a73-\u1a7c\u1a7f\u1b00-\u1b03\u1b34\u1b36-\u1b3a\u1b3c\u1b42\u1b6b-\u1b73\u1b80\u1b81\u1ba2-\u1ba5\u1ba8\u1ba9\u1c2c-\u1c33\u1c36\u1c37\u1cd0-\u1cd2\u1cd4-\u1ce0\u1ce2-\u1ce8\u1ced\u1dc0-\u1de6\u1dfd-\u1dff\u200c\u200d\u20d0-\u20f0\u2cef-\u2cf1\u2de0-\u2dff\u302a-\u302f\u3099\u309a\ua66f-\ua672\ua67c\ua67d\ua6f0\ua6f1\ua802\ua806\ua80b\ua825\ua826\ua8c4\ua8e0-\ua8f1\ua926-\ua92d\ua947-\ua951\ua980-\ua982\ua9b3\ua9b6-\ua9b9\ua9bc\uaa29-\uaa2e\uaa31\uaa32\uaa35\uaa36\uaa43\uaa4c\uaab0\uaab2-\uaab4\uaab7\uaab8\uaabe\uaabf\uaac1\uabe5\uabe8\uabed\udc00-\udfff\ufb1e\ufe00-\ufe0f\ufe20-\ufe26\uff9e\uff9f]/;
  
      function isExtendingChar(ch) {
          return ch.charCodeAt(0) >= 768 && extendingChars.test(ch);
      }
  
      // DOM UTILITIES
  
      function elt(tag, content, className, style) {
          var e = document.createElement(tag);
          if (className) e.className = className;
          if (style) e.style.cssText = style;
          if (typeof content == "string") e.appendChild(document.createTextNode(content));
          else if (content) for (var i = 0; i < content.length; ++i) e.appendChild(content[i]);
          return e;
      }
  
      var range;
      if (document.createRange) range = function (node, start, end, endNode) {
          var r = document.createRange();
          r.setEnd(endNode || node, end);
          r.setStart(node, start);
          return r;
      };
      else range = function (node, start, end) {
          var r = document.body.createTextRange();
          try {
              r.moveToElementText(node.parentNode);
          }
          catch (e) {
              return r;
          }
          r.collapse(true);
          r.moveEnd("character", end);
          r.moveStart("character", start);
          return r;
      };
  
      function removeChildren(e) {
          for (var count = e.childNodes.length; count > 0; --count)
              e.removeChild(e.firstChild);
          return e;
      }
  
      function removeChildrenAndAdd(parent, e) {
          return removeChildren(parent).appendChild(e);
      }
  
      var contains = CodeMirror.contains = function (parent, child) {
          if (child.nodeType == 3) // Android browser always returns false when child is a textnode
              child = child.parentNode;
          if (parent.contains)
              return parent.contains(child);
          do {
              if (child.nodeType == 11) child = child.host;
              if (child == parent) return true;
          } while (child = child.parentNode);
      };
  
      function activeElt() {
          return document.activeElement;
      }
  
      // Older versions of IE throws unspecified error when touching
      // document.activeElement in some cases (during loading, in iframe)
      if (ie && ie_version < 11) activeElt = function () {
          try {
              return document.activeElement;
          }
          catch (e) {
              return document.body;
          }
      };
  
      function classTest(cls) {
          return new RegExp("(^|\\s)" + cls + "(?:$|\\s)\\s*");
      }
  
      var rmClass = CodeMirror.rmClass = function (node, cls) {
          var current = node.className;
          var match = classTest(cls).exec(current);
          if (match) {
              var after = current.slice(match.index + match[0].length);
              node.className = current.slice(0, match.index) + (after ? match[1] + after : "");
          }
      };
      var addClass = CodeMirror.addClass = function (node, cls) {
          var current = node.className;
          if (!classTest(cls).test(current)) node.className += (current ? " " : "") + cls;
      };
  
      function joinClasses(a, b) {
          var as = a.split(" ");
          for (var i = 0; i < as.length; i++)
              if (as[i] && !classTest(as[i]).test(b)) b += " " + as[i];
          return b;
      }
  
      // WINDOW-WIDE EVENTS
  
      // These must be handled carefully, because naively registering a
      // handler for each editor will cause the editors to never be
      // garbage collected.
  
      function forEachCodeMirror(f) {
          if (!document.body.getElementsByClassName) return;
          var byClass = document.body.getElementsByClassName("CodeMirror");
          for (var i = 0; i < byClass.length; i++) {
              var cm = byClass[i].CodeMirror;
              if (cm) f(cm);
          }
      }
  
      var globalsRegistered = false;
  
      function ensureGlobalHandlers() {
          if (globalsRegistered) return;
          registerGlobalHandlers();
          globalsRegistered = true;
      }
  
      function registerGlobalHandlers() {
          // When the window resizes, we need to refresh active editors.
          var resizeTimer;
          on(window, "resize", function () {
              if (resizeTimer == null) resizeTimer = setTimeout(function () {
                  resizeTimer = null;
                  forEachCodeMirror(onResize);
              }, 100);
          });
          // When the window loses focus, we want to show the editor as blurred
          on(window, "blur", function () {
              forEachCodeMirror(onBlur);
          });
      }
  
      // FEATURE DETECTION
  
      // Detect drag-and-drop
      var dragAndDrop = function () {
          // There is *some* kind of drag-and-drop support in IE6-8, but I
          // couldn't get it to work yet.
          if (ie && ie_version < 9) return false;
          var div = elt('div');
          return "draggable" in div || "dragDrop" in div;
      }();
  
      var zwspSupported;
  
      function zeroWidthElement(measure) {
          if (zwspSupported == null) {
              var test = elt("span", "\u200b");
              removeChildrenAndAdd(measure, elt("span", [test, document.createTextNode("x")]));
              if (measure.firstChild.offsetHeight != 0)
                  zwspSupported = test.offsetWidth <= 1 && test.offsetHeight > 2 && !(ie && ie_version < 8);
          }
          var node = zwspSupported ? elt("span", "\u200b") :
              elt("span", "\u00a0", null, "display: inline-block; width: 1px; margin-right: -1px");
          node.setAttribute("cm-text", "");
          return node;
      }
  
      // Feature-detect IE's crummy client rect reporting for bidi text
      var badBidiRects;
  
      function hasBadBidiRects(measure) {
          if (badBidiRects != null) return badBidiRects;
          var txt = removeChildrenAndAdd(measure, document.createTextNode("A\u062eA"));
          var r0 = range(txt, 0, 1).getBoundingClientRect();
          if (!r0 || r0.left == r0.right) return false; // Safari returns null in some cases (#2780)
          var r1 = range(txt, 1, 2).getBoundingClientRect();
          return badBidiRects = (r1.right - r0.right < 3);
      }
  
      // See if "".split is the broken IE version, if so, provide an
      // alternative way to split lines.
      var splitLines = CodeMirror.splitLines = "\n\nb".split(/\n/).length != 3 ? function (string) {
          var pos = 0, result = [], l = string.length;
          while (pos <= l) {
              var nl = string.indexOf("\n", pos);
              if (nl == -1) nl = string.length;
              var line = string.slice(pos, string.charAt(nl - 1) == "\r" ? nl - 1 : nl);
              var rt = line.indexOf("\r");
              if (rt != -1) {
                  result.push(line.slice(0, rt));
                  pos += rt + 1;
              } else {
                  result.push(line);
                  pos = nl + 1;
              }
          }
          return result;
      } : function (string) {
          return string.split(/\r\n?|\n/);
      };
  
      var hasSelection = window.getSelection ? function (te) {
          try {
              return te.selectionStart != te.selectionEnd;
          }
          catch (e) {
              return false;
          }
      } : function (te) {
          try {
              var range = te.ownerDocument.selection.createRange();
          }
          catch (e) {
          }
          if (!range || range.parentElement() != te) return false;
          return range.compareEndPoints("StartToEnd", range) != 0;
      };
  
      var hasCopyEvent = (function () {
          var e = elt("div");
          if ("oncopy" in e) return true;
          e.setAttribute("oncopy", "return;");
          return typeof e.oncopy == "function";
      })();
  
      var badZoomedRects = null;
  
      function hasBadZoomedRects(measure) {
          if (badZoomedRects != null) return badZoomedRects;
          var node = removeChildrenAndAdd(measure, elt("span", "x"));
          var normal = node.getBoundingClientRect();
          var fromRange = range(node, 0, 1).getBoundingClientRect();
          return badZoomedRects = Math.abs(normal.left - fromRange.left) > 1;
      }
  
      // KEY NAMES
  
      var keyNames = {
          3: "Enter", 8: "Backspace", 9: "Tab", 13: "Enter", 16: "Shift", 17: "Ctrl", 18: "Alt",
          19: "Pause", 20: "CapsLock", 27: "Esc", 32: "Space", 33: "PageUp", 34: "PageDown", 35: "End",
          36: "Home", 37: "Left", 38: "Up", 39: "Right", 40: "Down", 44: "PrintScrn", 45: "Insert",
          46: "Delete", 59: ";", 61: "=", 91: "Mod", 92: "Mod", 93: "Mod", 107: "=", 109: "-", 127: "Delete",
          173: "-", 186: ";", 187: "=", 188: ",", 189: "-", 190: ".", 191: "/", 192: "`", 219: "[", 220: "\\",
          221: "]", 222: "'", 63232: "Up", 63233: "Down", 63234: "Left", 63235: "Right", 63272: "Delete",
          63273: "Home", 63275: "End", 63276: "PageUp", 63277: "PageDown", 63302: "Insert"
      };
      CodeMirror.keyNames = keyNames;
      (function () {
          // Number keys
          for (var i = 0; i < 10; i++) keyNames[i + 48] = keyNames[i + 96] = String(i);
          // Alphabetic keys
          for (var i = 65; i <= 90; i++) keyNames[i] = String.fromCharCode(i);
          // Function keys
          for (var i = 1; i <= 12; i++) keyNames[i + 111] = keyNames[i + 63235] = "F" + i;
      })();
  
      // BIDI HELPERS
  
      function iterateBidiSections(order, from, to, f) {
          if (!order) return f(from, to, "ltr");
          var found = false;
          for (var i = 0; i < order.length; ++i) {
              var part = order[i];
              if (part.from < to && part.to > from || from == to && part.to == from) {
                  f(Math.max(part.from, from), Math.min(part.to, to), part.level == 1 ? "rtl" : "ltr");
                  found = true;
              }
          }
          if (!found) f(from, to, "ltr");
      }
  
      function bidiLeft(part) {
          return part.level % 2 ? part.to : part.from;
      }
  
      function bidiRight(part) {
          return part.level % 2 ? part.from : part.to;
      }
  
      function lineLeft(line) {
          var order = getOrder(line);
          return order ? bidiLeft(order[0]) : 0;
      }
  
      function lineRight(line) {
          var order = getOrder(line);
          if (!order) return line.text.length;
          return bidiRight(lst(order));
      }
  
      function lineStart(cm, lineN) {
          var line = getLine(cm.doc, lineN);
          var visual = visualLine(line);
          if (visual != line) lineN = lineNo(visual);
          var order = getOrder(visual);
          var ch = !order ? 0 : order[0].level % 2 ? lineRight(visual) : lineLeft(visual);
          return Pos(lineN, ch);
      }
  
      function lineEnd(cm, lineN) {
          var merged, line = getLine(cm.doc, lineN);
          while (merged = collapsedSpanAtEnd(line)) {
              line = merged.find(1, true).line;
              lineN = null;
          }
          var order = getOrder(line);
          var ch = !order ? line.text.length : order[0].level % 2 ? lineLeft(line) : lineRight(line);
          return Pos(lineN == null ? lineNo(line) : lineN, ch);
      }
  
      function lineStartSmart(cm, pos) {
          var start = lineStart(cm, pos.line);
          var line = getLine(cm.doc, start.line);
          var order = getOrder(line);
          if (!order || order[0].level == 0) {
              var firstNonWS = Math.max(0, line.text.search(/\S/));
              var inWS = pos.line == start.line && pos.ch <= firstNonWS && pos.ch;
              return Pos(start.line, inWS ? 0 : firstNonWS);
          }
          return start;
      }
  
      function compareBidiLevel(order, a, b) {
          var linedir = order[0].level;
          if (a == linedir) return true;
          if (b == linedir) return false;
          return a < b;
      }
  
      var bidiOther;
  
      function getBidiPartAt(order, pos) {
          bidiOther = null;
          for (var i = 0, found; i < order.length; ++i) {
              var cur = order[i];
              if (cur.from < pos && cur.to > pos) return i;
              if ((cur.from == pos || cur.to == pos)) {
                  if (found == null) {
                      found = i;
                  } else if (compareBidiLevel(order, cur.level, order[found].level)) {
                      if (cur.from != cur.to) bidiOther = found;
                      return i;
                  } else {
                      if (cur.from != cur.to) bidiOther = i;
                      return found;
                  }
              }
          }
          return found;
      }
  
      function moveInLine(line, pos, dir, byUnit) {
          if (!byUnit) return pos + dir;
          do pos += dir;
          while (pos > 0 && isExtendingChar(line.text.charAt(pos)));
          return pos;
      }
  
      // This is needed in order to move 'visually' through bi-directional
      // text -- i.e., pressing left should make the cursor go left, even
      // when in RTL text. The tricky part is the 'jumps', where RTL and
      // LTR text touch each other. This often requires the cursor offset
      // to move more than one unit, in order to visually move one unit.
      function moveVisually(line, start, dir, byUnit) {
          var bidi = getOrder(line);
          if (!bidi) return moveLogically(line, start, dir, byUnit);
          var pos = getBidiPartAt(bidi, start), part = bidi[pos];
          var target = moveInLine(line, start, part.level % 2 ? -dir : dir, byUnit);
  
          for (; ;) {
              if (target > part.from && target < part.to) return target;
              if (target == part.from || target == part.to) {
                  if (getBidiPartAt(bidi, target) == pos) return target;
                  part = bidi[pos += dir];
                  return (dir > 0) == part.level % 2 ? part.to : part.from;
              } else {
                  part = bidi[pos += dir];
                  if (!part) return null;
                  if ((dir > 0) == part.level % 2)
                      target = moveInLine(line, part.to, -1, byUnit);
                  else
                      target = moveInLine(line, part.from, 1, byUnit);
              }
          }
      }
  
      function moveLogically(line, start, dir, byUnit) {
          var target = start + dir;
          if (byUnit) while (target > 0 && isExtendingChar(line.text.charAt(target))) target += dir;
          return target < 0 || target > line.text.length ? null : target;
      }
  
      // Bidirectional ordering algorithm
      // See http://unicode.org/reports/tr9/tr9-13.html for the algorithm
      // that this (partially) implements.
  
      // One-char codes used for character types:
      // L (L):   Left-to-Right
      // R (R):   Right-to-Left
      // r (AL):  Right-to-Left Arabic
      // 1 (EN):  European Number
      // + (ES):  European Number Separator
      // % (ET):  European Number Terminator
      // n (AN):  Arabic Number
      // , (CS):  Common Number Separator
      // m (NSM): Non-Spacing Mark
      // b (BN):  Boundary Neutral
      // s (B):   Paragraph Separator
      // t (S):   Segment Separator
      // w (WS):  Whitespace
      // N (ON):  Other Neutrals
  
      // Returns null if characters are ordered as they appear
      // (left-to-right), or an array of sections ({from, to, level}
      // objects) in the order in which they occur visually.
      var bidiOrdering = (function () {
          // Character types for codepoints 0 to 0xff
          var lowTypes = "bbbbbbbbbtstwsbbbbbbbbbbbbbbssstwNN%%%NNNNNN,N,N1111111111NNNNNNNLLLLLLLLLLLLLLLLLLLLLLLLLLNNNNNNLLLLLLLLLLLLLLLLLLLLLLLLLLNNNNbbbbbbsbbbbbbbbbbbbbbbbbbbbbbbbbb,N%%%%NNNNLNNNNN%%11NLNNN1LNNNNNLLLLLLLLLLLLLLLLLLLLLLLNLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLN";
          // Character types for codepoints 0x600 to 0x6ff
          var arabicTypes = "rrrrrrrrrrrr,rNNmmmmmmrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrmmmmmmmmmmmmmmrrrrrrrnnnnnnnnnn%nnrrrmrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrmmmmmmmmmmmmmmmmmmmNmmmm";
  
          function charType(code) {
              if (code <= 0xf7) return lowTypes.charAt(code);
              else if (0x590 <= code && code <= 0x5f4) return "R";
              else if (0x600 <= code && code <= 0x6ed) return arabicTypes.charAt(code - 0x600);
              else if (0x6ee <= code && code <= 0x8ac) return "r";
              else if (0x2000 <= code && code <= 0x200b) return "w";
              else if (code == 0x200c) return "b";
              else return "L";
          }
  
          var bidiRE = /[\u0590-\u05f4\u0600-\u06ff\u0700-\u08ac]/;
          var isNeutral = /[stwN]/, isStrong = /[LRr]/, countsAsLeft = /[Lb1n]/, countsAsNum = /[1n]/;
          // Browsers seem to always treat the boundaries of block elements as being L.
          var outerType = "L";
  
          function BidiSpan(level, from, to) {
              this.level = level;
              this.from = from;
              this.to = to;
          }
  
          return function (str) {
              if (!bidiRE.test(str)) return false;
              var len = str.length, types = [];
              for (var i = 0, type; i < len; ++i)
                  types.push(type = charType(str.charCodeAt(i)));
  
              // W1. Examine each non-spacing mark (NSM) in the level run, and
              // change the type of the NSM to the type of the previous
              // character. If the NSM is at the start of the level run, it will
              // get the type of sor.
              for (var i = 0, prev = outerType; i < len; ++i) {
                  var type = types[i];
                  if (type == "m") types[i] = prev;
                  else prev = type;
              }
  
              // W2. Search backwards from each instance of a European number
              // until the first strong type (R, L, AL, or sor) is found. If an
              // AL is found, change the type of the European number to Arabic
              // number.
              // W3. Change all ALs to R.
              for (var i = 0, cur = outerType; i < len; ++i) {
                  var type = types[i];
                  if (type == "1" && cur == "r") types[i] = "n";
                  else if (isStrong.test(type)) {
                      cur = type;
                      if (type == "r") types[i] = "R";
                  }
              }
  
              // W4. A single European separator between two European numbers
              // changes to a European number. A single common separator between
              // two numbers of the same type changes to that type.
              for (var i = 1, prev = types[0]; i < len - 1; ++i) {
                  var type = types[i];
                  if (type == "+" && prev == "1" && types[i + 1] == "1") types[i] = "1";
                  else if (type == "," && prev == types[i + 1] &&
                      (prev == "1" || prev == "n")) types[i] = prev;
                  prev = type;
              }
  
              // W5. A sequence of European terminators adjacent to European
              // numbers changes to all European numbers.
              // W6. Otherwise, separators and terminators change to Other
              // Neutral.
              for (var i = 0; i < len; ++i) {
                  var type = types[i];
                  if (type == ",") types[i] = "N";
                  else if (type == "%") {
                      for (var end = i + 1; end < len && types[end] == "%"; ++end) {
                      }
                      var replace = (i && types[i - 1] == "!") || (end < len && types[end] == "1") ? "1" : "N";
                      for (var j = i; j < end; ++j) types[j] = replace;
                      i = end - 1;
                  }
              }
  
              // W7. Search backwards from each instance of a European number
              // until the first strong type (R, L, or sor) is found. If an L is
              // found, then change the type of the European number to L.
              for (var i = 0, cur = outerType; i < len; ++i) {
                  var type = types[i];
                  if (cur == "L" && type == "1") types[i] = "L";
                  else if (isStrong.test(type)) cur = type;
              }
  
              // N1. A sequence of neutrals takes the direction of the
              // surrounding strong text if the text on both sides has the same
              // direction. European and Arabic numbers act as if they were R in
              // terms of their influence on neutrals. Start-of-level-run (sor)
              // and end-of-level-run (eor) are used at level run boundaries.
              // N2. Any remaining neutrals take the embedding direction.
              for (var i = 0; i < len; ++i) {
                  if (isNeutral.test(types[i])) {
                      for (var end = i + 1; end < len && isNeutral.test(types[end]); ++end) {
                      }
                      var before = (i ? types[i - 1] : outerType) == "L";
                      var after = (end < len ? types[end] : outerType) == "L";
                      var replace = before || after ? "L" : "R";
                      for (var j = i; j < end; ++j) types[j] = replace;
                      i = end - 1;
                  }
              }
  
              // Here we depart from the documented algorithm, in order to avoid
              // building up an actual levels array. Since there are only three
              // levels (0, 1, 2) in an implementation that doesn't take
              // explicit embedding into account, we can build up the order on
              // the fly, without following the level-based algorithm.
              var order = [], m;
              for (var i = 0; i < len;) {
                  if (countsAsLeft.test(types[i])) {
                      var start = i;
                      for (++i; i < len && countsAsLeft.test(types[i]); ++i) {
                      }
                      order.push(new BidiSpan(0, start, i));
                  } else {
                      var pos = i, at = order.length;
                      for (++i; i < len && types[i] != "L"; ++i) {
                      }
                      for (var j = pos; j < i;) {
                          if (countsAsNum.test(types[j])) {
                              if (pos < j) order.splice(at, 0, new BidiSpan(1, pos, j));
                              var nstart = j;
                              for (++j; j < i && countsAsNum.test(types[j]); ++j) {
                              }
                              order.splice(at, 0, new BidiSpan(2, nstart, j));
                              pos = j;
                          } else ++j;
                      }
                      if (pos < i) order.splice(at, 0, new BidiSpan(1, pos, i));
                  }
              }
              if (order[0].level == 1 && (m = str.match(/^\s+/))) {
                  order[0].from = m[0].length;
                  order.unshift(new BidiSpan(0, 0, m[0].length));
              }
              if (lst(order).level == 1 && (m = str.match(/\s+$/))) {
                  lst(order).to -= m[0].length;
                  order.push(new BidiSpan(0, len - m[0].length, len));
              }
              if (order[0].level != lst(order).level)
                  order.push(new BidiSpan(order[0].level, len, len));
  
              return order;
          };
      })();
  
      // THE END
  
      CodeMirror.version = "5.0.0";
  
      return CodeMirror;
  });
  