text: // CodeMirror, 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 (global, factory) {
    typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
    typeof define === 'function' && define.amd ? define(factory) :
    (global.CodeMirror = factory());
  }(this, (function () { 'use strict';
  
  // Kludges for bugs and behavior differences that can't be feature
  // detected are enabled based on userAgent etc sniffing.
  var userAgent = navigator.userAgent
  var platform = navigator.platform
  
  var gecko = /gecko\/\d/i.test(userAgent)
  var ie_upto10 = /MSIE \d/.test(userAgent)
  var ie_11up = /Trident\/(?:[7-9]|\d{2,})\..*rv:(\d+)/.exec(userAgent)
  var ie = ie_upto10 || ie_11up
  var ie_version = ie && (ie_upto10 ? document.documentMode || 6 : ie_11up[1])
  var webkit = /WebKit\//.test(userAgent)
  var qtwebkit = webkit && /Qt\/\d+\.\d+/.test(userAgent)
  var chrome = /Chrome\//.test(userAgent)
  var presto = /Opera\//.test(userAgent)
  var safari = /Apple Computer/.test(navigator.vendor)
  var mac_geMountainLion = /Mac OS X 1\d\D([8-9]|\d\d)\D/.test(userAgent)
  var phantom = /PhantomJS/.test(userAgent)
  
  var ios = /AppleWebKit/.test(userAgent) && /Mobile\/\w+/.test(userAgent)
  // This is woefully incomplete. Suggestions for alternative methods welcome.
  var mobile = ios || /Android|webOS|BlackBerry|Opera Mini|Opera Mobi|IEMobile/i.test(userAgent)
  var mac = ios || /Mac/.test(platform)
  var chromeOS = /\bCrOS\b/.test(userAgent)
  var windows = /win/i.test(platform)
  
  var presto_version = presto && 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)
  
  function classTest(cls) { return new RegExp("(^|\\s)" + cls + "(?:$|\\s)\\s*") }
  
  var 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 : "")
    }
  }
  
  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)
  }
  
  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 contains(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)
  }
  
  var activeElt = function() {
    var activeElement = document.activeElement
    while (activeElement && activeElement.root && activeElement.root.activeElement)
      { activeElement = activeElement.root.activeElement }
    return 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 addClass(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
  }
  
  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 bind(f) {
    var args = Array.prototype.slice.call(arguments, 1)
    return function(){return f.apply(null, args)}
  }
  
  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
  }
  
  // Counts the column offset in a string, taking tabs into account.
  // Used mostly to find indentation.
  function countColumn(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
    }
  }
  
  function Delayed() {this.id = null}
  Delayed.prototype.set = function(ms, f) {
    clearTimeout(this.id)
    this.id = setTimeout(f, ms)
  }
  
  function indexOf(array, elt) {
    for (var i = 0; i < array.length; ++i)
      { if (array[i] == elt) { return i } }
    return -1
  }
  
  // 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 = {toString: function(){return "CodeMirror.Pass"}}
  
  // Reused option objects for setSelection & friends
  var sel_dontScroll = {scroll: false};
  var sel_mouse = {origin: "*mouse"};
  var sel_move = {origin: "+move"}
  
  // 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] }
  
  function map(array, f) {
    var out = []
    for (var i = 0; i < array.length; i++) { out[i] = f(array[i], i) }
    return out
  }
  
  function insertSorted(array, value, score) {
    var pos = 0, priority = score(value)
    while (pos < array.length && score(array[pos]) <= priority) { pos++ }
    array.splice(pos, 0, value)
  }
  
  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
  }
  
  var nonASCIISingleCaseWordChar = /[\u00df\u0587\u0590-\u05f4\u0600-\u06ff\u3040-\u309f\u30a0-\u30ff\u3400-\u4db5\u4e00-\u9fcc\uac00-\ud7af]/
  function isWordCharBasic(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) }
  
  // 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)
  }
  
  // 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.") }
    var chunk = doc
    while (!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) }) // iter aborts when callback returns truthy value
    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$1 = 0; i$1 < chunk.children.length; ++i$1) {
        var child = chunk.children[i$1], ch = child.height
        if (h < ch) { chunk = child; continue outer }
        h -= ch
        n += child.chunkSize()
      }
      return n
    } while (!chunk.lines)
    var i = 0
    for (; i < chunk.lines.length; ++i) {
      var line = chunk.lines[i], lh = line.height
      if (h < lh) { break }
      h -= lh
    }
    return n + i
  }
  
  function isLine(doc, l) {return l >= doc.first && l < doc.first + doc.size}
  
  function lineNumberFor(options, i) {
    return String(options.lineNumberFormatter(i + options.firstLineNumber))
  }
  
  // A Pos instance represents a position within the text.
  function Pos (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.
  function cmp(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 }
  
  // 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 clipPosArray(doc, array) {
    var out = []
    for (var i = 0; i < array.length; i++) { out[i] = clipPos(doc, array[i]) }
    return out
  }
  
  // Optimize some code when these features are not used.
  var sawReadOnlySpans = false;
  var sawCollapsedSpans = false
  
  function seeReadOnlySpans() {
    sawReadOnlySpans = true
  }
  
  function seeCollapsedSpans() {
    sawCollapsedSpans = true
  }
  
  // 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) {
    var r
    for (var 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) {
    var nw
    if (old) { for (var i = 0; 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) {
    var nw
    if (old) { for (var i = 0; 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$1 = 0; i$1 < last.length; ++i$1) {
        var span$1 = last[i$1]
        if (span$1.to != null) { span$1.to += offset }
        if (span$1.from == null) {
          var found$1 = getMarkedSpanFor(first, span$1.marker)
          if (!found$1) {
            span$1.from = offset
            if (sameLine) { (first || (first = [])).push(span$1) }
          }
        } else {
          span$1.from += offset
          if (sameLine) { (first || (first = [])).push(span$1) }
        }
      }
    }
    // 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$2 = 0; i$2 < first.length; ++i$2)
          { if (first[i$2].to == null)
            { (gapMarkers || (gapMarkers = [])).push(new MarkedSpan(first[i$2].marker, null, null)) } } }
      for (var i$3 = 0; i$3 < gap; ++i$3)
        { 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 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 = void 0, 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$$1, from, to, marker) {
    var line = getLine(doc, lineNo$$1)
    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 && (sp.marker.inclusiveRight && marker.inclusiveLeft ? cmp(found.to, from) >= 0 : cmp(found.to, from) > 0) ||
          fromCmp >= 0 && (sp.marker.inclusiveRight && marker.inclusiveLeft ? cmp(found.from, to) <= 0 : cmp(found.from, to) < 0))
        { 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 = void 0, 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 = void 0, 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 }
    }
  }
  
  // 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$1 = 0; i$1 < p.children.length; ++i$1) {
        var cur = p.children[i$1]
        if (cur == chunk) { break }
        else { h += cur.height }
      }
    }
    return h
  }
  
  // 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$1 = merged.find(0, true)
      len -= cur.text.length - found$1.from.ch
      cur = found$1.to.line
      len += cur.text.length - found$1.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
      }
    })
  }
  
  // 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 compareBidiLevel(order, a, b) {
    var linedir = order[0].level
    if (a == linedir) { return true }
    if (b == linedir) { return false }
    return a < b
  }
  
  var bidiOther = null
  function getBidiPartAt(order, pos) {
    var found
    bidiOther = null
    for (var i = 0; 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; i < len; ++i)
        { types.push(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$1 = 0, prev = outerType; i$1 < len; ++i$1) {
        var type = types[i$1]
        if (type == "m") { types[i$1] = 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$2 = 0, cur = outerType; i$2 < len; ++i$2) {
        var type$1 = types[i$2]
        if (type$1 == "1" && cur == "r") { types[i$2] = "n" }
        else if (isStrong.test(type$1)) { cur = type$1; if (type$1 == "r") { types[i$2] = "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$3 = 1, prev$1 = types[0]; i$3 < len - 1; ++i$3) {
        var type$2 = types[i$3]
        if (type$2 == "+" && prev$1 == "1" && types[i$3+1] == "1") { types[i$3] = "1" }
        else if (type$2 == "," && prev$1 == types[i$3+1] &&
                 (prev$1 == "1" || prev$1 == "n")) { types[i$3] = prev$1 }
        prev$1 = type$2
      }
  
      // 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$4 = 0; i$4 < len; ++i$4) {
        var type$3 = types[i$4]
        if (type$3 == ",") { types[i$4] = "N" }
        else if (type$3 == "%") {
          var end = void 0
          for (end = i$4 + 1; end < len && types[end] == "%"; ++end) {}
          var replace = (i$4 && types[i$4-1] == "!") || (end < len && types[end] == "1") ? "1" : "N"
          for (var j = i$4; j < end; ++j) { types[j] = replace }
          i$4 = 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$5 = 0, cur$1 = outerType; i$5 < len; ++i$5) {
        var type$4 = types[i$5]
        if (cur$1 == "L" && type$4 == "1") { types[i$5] = "L" }
        else if (isStrong.test(type$4)) { cur$1 = type$4 }
      }
  
      // 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$6 = 0; i$6 < len; ++i$6) {
        if (isNeutral.test(types[i$6])) {
          var end$1 = void 0
          for (end$1 = i$6 + 1; end$1 < len && isNeutral.test(types[end$1]); ++end$1) {}
          var before = (i$6 ? types[i$6-1] : outerType) == "L"
          var after = (end$1 < len ? types[end$1] : outerType) == "L"
          var replace$1 = before || after ? "L" : "R"
          for (var j$1 = i$6; j$1 < end$1; ++j$1) { types[j$1] = replace$1 }
          i$6 = end$1 - 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$7 = 0; i$7 < len;) {
        if (countsAsLeft.test(types[i$7])) {
          var start = i$7
          for (++i$7; i$7 < len && countsAsLeft.test(types[i$7]); ++i$7) {}
          order.push(new BidiSpan(0, start, i$7))
        } else {
          var pos = i$7, at = order.length
          for (++i$7; i$7 < len && types[i$7] != "L"; ++i$7) {}
          for (var j$2 = pos; j$2 < i$7;) {
            if (countsAsNum.test(types[j$2])) {
              if (pos < j$2) { order.splice(at, 0, new BidiSpan(1, pos, j$2)) }
              var nstart = j$2
              for (++j$2; j$2 < i$7 && countsAsNum.test(types[j$2]); ++j$2) {}
              order.splice(at, 0, new BidiSpan(2, nstart, j$2))
              pos = j$2
            } else { ++j$2 }
          }
          if (pos < i$7) { order.splice(at, 0, new BidiSpan(1, pos, i$7)) }
        }
      }
      if (order[0].level == 1 && (m = str.match(/^\s+/))) {
        order[0].from = m[0].length
        order.unshift(new BidiSpan(0, 0, m[0].length))
      }
      if (lst(order).level == 1 && (m = str.match(/\s+$/))) {
        lst(order).to -= m[0].length
        order.push(new BidiSpan(0, len - m[0].length, len))
      }
      if (order[0].level == 2)
        { order.unshift(new BidiSpan(1, order[0].to, order[0].to)) }
      if (order[0].level != lst(order).level)
        { order.push(new BidiSpan(order[0].level, len, len)) }
  
      return order
    }
  })()
  
  // 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
  }
  
  // EVENT HANDLING
  
  // Lightweight event framework. on/off also work on DOM nodes,
  // registering native DOM handlers.
  
  var 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$$1 = emitter._handlers || (emitter._handlers = {})
      var arr = map$$1[type] || (map$$1[type] = [])
      arr.push(f)
    }
  }
  
  var noHandlers = []
  function getHandlers(emitter, type, copy) {
    var arr = emitter._handlers && emitter._handlers[type]
    if (copy) { return arr && arr.length > 0 ? arr.slice() : noHandlers }
    else { return arr || noHandlers }
  }
  
  function off(emitter, type, f) {
    if (emitter.removeEventListener)
      { emitter.removeEventListener(type, f, false) }
    else if (emitter.detachEvent)
      { emitter.detachEvent("on" + type, f) }
    else {
      var handlers = getHandlers(emitter, type, false)
      for (var i = 0; i < handlers.length; ++i)
        { if (handlers[i] == f) { handlers.splice(i, 1); break } }
    }
  }
  
  function signal(emitter, type /*, values...*/) {
    var handlers = getHandlers(emitter, type, true)
    if (!handlers.length) { return }
    var args = Array.prototype.slice.call(arguments, 2)
    for (var i = 0; i < handlers.length; ++i) { handlers[i].apply(null, args) }
  }
  
  // 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) {
    return getHandlers(emitter, type).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)}
  }
  
  // Due to the fact that we still support jurassic IE versions, some
  // compatibility wrappers are needed.
  
  function e_preventDefault(e) {
    if (e.preventDefault) { e.preventDefault() }
    else { e.returnValue = false }
  }
  function e_stopPropagation(e) {
    if (e.stopPropagation) { e.stopPropagation() }
    else { e.cancelBubble = true }
  }
  function e_defaultPrevented(e) {
    return e.defaultPrevented != null ? e.defaultPrevented : e.returnValue == false
  }
  function e_stop(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
  }
  
  // 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()
    var r1 = range(txt, 1, 2).getBoundingClientRect()
    removeChildren(measure)
    if (!r0 || r0.left == r0.right) { return false } // Safari returns null in some cases (#2780)
    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 splitLinesAuto = "\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) {
    var range$$1
    try {range$$1 = te.ownerDocument.selection.createRange()}
    catch(e) {}
    if (!range$$1 || range$$1.parentElement() != te) { return false }
    return range$$1.compareEndPoints("StartToEnd", range$$1) != 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
  }
  
  // Known modes, by name and by MIME
  var modes = {};
  var 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.)
  function defineMode(name, mode) {
    if (arguments.length > 2)
      { mode.dependencies = Array.prototype.slice.call(arguments, 2) }
    modes[name] = mode
  }
  
  function defineMIME(mime, spec) {
    mimeModes[mime] = spec
  }
  
  // Given a MIME type, a {name, ...options} config object, or a name
  // string, return a mode config object.
  function resolveMode(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$/.test(spec)) {
      return resolveMode("application/xml")
    } else if (typeof spec == "string" && /^[\w\-]+\/[\w\-]+\+json$/.test(spec)) {
      return resolveMode("application/json")
    }
    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.
  function getMode(options, spec) {
    spec = resolveMode(spec)
    var mfactory = modes[spec.name]
    if (!mfactory) { return 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$1 in spec.modeProps)
      { modeObj[prop$1] = spec.modeProps[prop$1] } }
  
    return modeObj
  }
  
  // This can be used to attach properties to mode objects from
  // outside the actual mode definition.
  var modeExtensions = {}
  function extendMode(mode, properties) {
    var exts = modeExtensions.hasOwnProperty(mode) ? modeExtensions[mode] : (modeExtensions[mode] = {})
    copyObj(properties, exts)
  }
  
  function copyState(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
  }
  
  // Given a mode and a state (for that mode), find the inner mode and
  // state at the position that the state refers to.
  function innerMode(mode, state) {
    var info
    while (mode.innerMode) {
      info = mode.innerMode(state)
      if (!info || info.mode == mode) { break }
      state = info.state
      mode = info.mode
    }
    return info || {mode: mode, state: state}
  }
  
  function startState(mode, a1, a2) {
    return mode.startState ? mode.startState(a1, a2) : true
  }
  
  // STRING STREAM
  
  // Fed to the mode parsers, provides helper functions to make
  // parsers more succinct.
  
  var 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)
      var ok
      if (typeof match == "string") { ok = ch == match }
      else { 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 this$1 = this;
  
      var start = this.pos
      while (/[\s\u00a0]/.test(this.string.charAt(this.pos))) { ++this$1.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 }
    }
  }
  
  // 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) { return st.push(end, style); },
      lineClasses, forceToEnd)
  
    // Run overlays, adjust style array.
    var loop = function ( 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, "overlay " + style)
          i = start + 2
        } else {
          for (; start < i; start += 2) {
            var cur = st[start+1]
            st[start+1] = (cur ? cur + " " : "") + "overlay " + style
          }
        }
      }, lineClasses)
    };
  
    for (var o = 0; o < cm.state.overlays.length; ++o) loop( o );
  
    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 state = getStateBefore(cm, lineNo(line))
      var result = highlightLine(cm, line, line.text.length > cm.options.maxHighlightLength ? copyState(cm.doc.mode, state) : state)
      line.stateAfter = state
      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
  }
  
  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
  }
  
  // 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()) {
      readToken(mode, stream, state)
      stream.start = stream.pos
    }
  }
  
  function callBlankLine(mode, state) {
    if (mode.blankLine) { return mode.blankLine(state) }
    if (!mode.innerMode) { return }
    var inner = 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] = 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) {
    var getObj = function (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()
  }
  
  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
  }
  
  // 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 + 5000)
          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, and returns inaccurate measurements in nodes
      // starting around 5000 chars.
      var pos = Math.min(stream.pos, curStart + 5000)
      f(pos, curStyle)
      curStart = pos
    }
  }
  
  // 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
  }
  
  // LINE DATA STRUCTURE
  
  // Line objects. These hold state related to a line, including
  // highlighting info (the styles array).
  function Line(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)
  }
  
  // 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 = {};
  var 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], "CodeMirror-line"), content: content,
                   col: 0, pos: 0, cm: cm,
                   trailingSpace: false,
                   splitSpaces: (ie || webkit) && cm.getOption("lineWrapping")}
    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 = void 0
      builder.pos = 0
      builder.addToken = buildToken
      // Optionally wire in some hacks into the token-rendering
      // algorithm, to deal with browser quirks.
      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) {
      var last = builder.content.lastChild
      if (/\bcm-tab\b/.test(last.className) || (last.querySelector && last.querySelector(".cm-tab")))
        { 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 displayText = builder.splitSpaces ? splitSpaces(text, builder.trailingSpace) : text
    var special = builder.cm.state.specialChars, mustWrap = false
    var content
    if (!special.test(text)) {
      builder.col += text.length
      content = document.createTextNode(displayText)
      builder.map.push(builder.pos, builder.pos + text.length, content)
      if (ie && ie_version < 9) { mustWrap = true }
      builder.pos += text.length
    } else {
      content = document.createDocumentFragment()
      var 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(displayText.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
        var txt$1 = void 0
        if (m[0] == "\t") {
          var tabSize = builder.cm.options.tabSize, tabWidth = tabSize - builder.col % tabSize
          txt$1 = content.appendChild(elt("span", spaceStr(tabWidth), "cm-tab"))
          txt$1.setAttribute("role", "presentation")
          txt$1.setAttribute("cm-text", "\t")
          builder.col += tabWidth
        } else if (m[0] == "\r" || m[0] == "\n") {
          txt$1 = content.appendChild(elt("span", m[0] == "\r" ? "\u240d" : "\u2424", "cm-invalidchar"))
          txt$1.setAttribute("cm-text", m[0])
          builder.col += 1
        } else {
          txt$1 = builder.cm.options.specialCharPlaceholder(m[0])
          txt$1.setAttribute("cm-text", m[0])
          if (ie && ie_version < 9) { content.appendChild(elt("span", [txt$1])) }
          else { content.appendChild(txt$1) }
          builder.col += 1
        }
        builder.map.push(builder.pos, builder.pos + 1, txt$1)
        builder.pos++
      }
    }
    builder.trailingSpace = displayText.charCodeAt(text.length - 1) == 32
    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 splitSpaces(text, trailingBefore) {
    if (text.length > 1 && !/  /.test(text)) { return text }
    var spaceBefore = trailingBefore, result = ""
    for (var i = 0; i < text.length; i++) {
      var ch = text.charAt(i)
      if (ch == " " && spaceBefore && (i == text.length - 1 || text.charCodeAt(i + 1) == 32))
        { ch = "\u00a0" }
      result += ch
      spaceBefore = ch == " "
    }
    return result
  }
  
  // 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, css) {
      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
        var part = void 0
        for (var i = 0; i < order.length; i++) {
          part = order[i]
          if (part.to > start && part.from <= start) { break }
        }
        if (part.to >= end) { return inner(builder, text, style, startStyle, endStyle, title, css) }
        inner(builder, text.slice(0, part.to - start), style, startStyle, null, title, css)
        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
    builder.trailingSpace = false
  }
  
  // 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 = 1; i$1 < styles.length; i$1+=2)
        { builder.addToken(builder, allText.slice(at, at = styles[i$1]), interpretTokenStyle(styles[i$1+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 = [], endStyles = void 0
        for (var j = 0; j < spans.length; ++j) {
          var sp = spans[j], m = sp.marker
          if (m.type == "bookmark" && sp.from == pos && m.widgetNode) {
            foundBookmarks.push(m)
          } else if (sp.from <= pos && (sp.to == null || sp.to > pos || m.collapsed && sp.to == pos && sp.from == pos)) {
            if (sp.to != null && sp.to != pos && nextChange > sp.to) {
              nextChange = sp.to
              spanEndStyle = ""
            }
            if (m.className) { spanStyle += " " + m.className }
            if (m.css) { css = (css ? css + ";" : "") + m.css }
            if (m.startStyle && sp.from == pos) { spanStartStyle += " " + m.startStyle }
            if (m.endStyle && sp.to == nextChange) { (endStyles || (endStyles = [])).push(m.endStyle, sp.to) }
            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 (endStyles) { for (var j$1 = 0; j$1 < endStyles.length; j$1 += 2)
          { if (endStyles[j$1 + 1] == nextChange) { spanEndStyle += " " + endStyles[j$1] } } }
  
        if (!collapsed || collapsed.from == pos) { for (var j$2 = 0; j$2 < foundBookmarks.length; ++j$2)
          { buildCollapsedSpan(builder, 0, foundBookmarks[j$2]) } }
        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.to == pos) { collapsed = false }
        }
      }
      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)
      }
    }
  }
  
  
  // 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
  }
  
  var operationGroup = null
  
  function pushOperation(op) {
    if (operationGroup) {
      operationGroup.ops.push(op)
    } else {
      op.ownsGroup = operationGroup = {
        ops: [op],
        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].call(null) }
      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++].call(null, op.cm) } }
      }
    } while (i < callbacks.length)
  }
  
  function finishOperation(op, endCb) {
    var group = op.ownsGroup
    if (!group) { return }
  
    try { fireCallbacksForOps(group) }
    finally {
      operationGroup = null
      endCb(group)
    }
  }
  
  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 = getHandlers(emitter, type, false)
    if (!arr.length) { 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)
    }
    var loop = function ( i ) {
      list.push(function () { return arr[i].apply(null, args); })
    };
  
    for (var i = 0; i < arr.length; ++i)
      loop( i );
  }
  
  function fireOrphanDelayed() {
    var delayed = orphanDelayedCallbacks
    orphanDelayedCallbacks = null
    for (var i = 0; i < delayed.length; ++i) { delayed[i]() }
  }
  
  // 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
    }
    if (lineView.gutterBackground) {
      lineView.node.removeChild(lineView.gutterBackground)
      lineView.gutterBackground = null
    }
    if (lineView.line.gutterClass) {
      var wrap = ensureLineWrapped(lineView)
      lineView.gutterBackground = elt("div", null, "CodeMirror-gutter-background " + lineView.line.gutterClass,
                                      ("left: " + (cm.options.fixedGutter ? dims.fixedPos : -dims.gutterTotalWidth) + "px; width: " + (dims.gutterTotalWidth) + "px"))
      wrap.insertBefore(lineView.gutterBackground, lineView.text)
    }
    var markers = lineView.line.gutterMarkers
    if (cm.options.lineNumbers || markers) {
      var wrap$1 = ensureLineWrapped(lineView)
      var gutterWrap = lineView.gutter = elt("div", null, "CodeMirror-gutter-wrapper", ("left: " + (cm.options.fixedGutter ? dims.fixedPos : -dims.gutterTotalWidth) + "px"))
      cm.display.input.setUneditable(gutterWrap)
      wrap$1.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 = void 0; node; node = next) {
      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" }
    }
  }
  
  function widgetHeight(widget) {
    if (widget.height != null) { return widget.height }
    var cm = widget.doc.cm
    if (!cm) { return 0 }
    if (!contains(document.body, widget.node)) {
      var parentStyle = "position: relative;"
      if (widget.coverGutter)
        { parentStyle += "margin-left: -" + cm.display.gutters.offsetWidth + "px;" }
      if (widget.noHScroll)
        { parentStyle += "width: " + cm.display.wrapper.clientWidth + "px;" }
      removeChildrenAndAdd(cm.display.measure, elt("div", [widget.node], null, parentStyle))
    }
    return widget.height = widget.node.parentNode.offsetHeight
  }
  
  // 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 }
    }
  }
  
  // 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$1 = 0; i$1 < lineView.rest.length; i$1++)
      { if (lineNo(lineView.rest[i$1]) > lineN)
        { return {map: lineView.measure.maps[i$1], cache: lineView.measure.caches[i$1], 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))
      cm.curOp.forceUpdate = true
    }
    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$$1, ch, bias) {
    var node, start, end, collapse, mStart, mEnd
    // First, search the line map for the text node corresponding to,
    // or closest to, the target character.
    for (var i = 0; i < map$$1.length; i += 3) {
      mStart = map$$1[i]
      mEnd = map$$1[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$$1.length - 3 || ch == mEnd && map$$1[i + 3] > ch) {
        end = mEnd - mStart
        start = end - 1
        if (ch >= mEnd) { collapse = "right" }
      }
      if (start != null) {
        node = map$$1[i + 2]
        if (mStart == mEnd && bias == (node.insertLeft ? "left" : "right"))
          { collapse = bias }
        if (bias == "left" && start == 0)
          { while (i && map$$1[i - 2] == map$$1[i - 3] && map$$1[i - 1].insertLeft) {
            node = map$$1[(i -= 3) + 2]
            collapse = "left"
          } }
        if (bias == "right" && start == mEnd - mStart)
          { while (i < map$$1.length - 3 && map$$1[i + 3] == map$$1[i + 4] && !map$$1[i + 5].insertLeft) {
            node = map$$1[(i += 3) + 2]
            collapse = "right"
          } }
        break
      }
    }
    return {node: node, start: start, end: end, collapse: collapse, coverStart: mStart, coverEnd: mEnd}
  }
  
  function getUsefulRect(rects, bias) {
    var rect = nullRect
    if (bias == "left") { for (var i = 0; i < rects.length; i++) {
      if ((rect = rects[i]).left != rect.right) { break }
    } } else { for (var i$1 = rects.length - 1; i$1 >= 0; i$1--) {
      if ((rect = rects[i$1]).left != rect.right) { break }
    } }
    return rect
  }
  
  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$1 = 0; i$1 < 4; i$1++) { // 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
          { rect = getUsefulRect(range(node, start, end).getClientRects(), bias) }
        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
    var i = 0
    for (; 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$$1, 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$$1, 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$$1, to, toOutside, 1) }
    // Do a binary search between these bounds.
    for (;;) {
      if (bidi ? to == from || to == moveVisually(lineObj, from, 1) : to - from <= 1) {
        var ch = x < fromX || x - fromX <= toX - x ? from : to
        var outside = ch == from ? fromOutside : toOutside
        var xDiff = x - (ch == from ? fromX : toX)
        // This is a kludge to handle the case where the coordinates
        // are after a line-wrapped line. We should replace it with a
        // more general handling of cursor positions around line
        // breaks. (Issue #4078)
        if (toOutside && !bidi && !/\s/.test(lineObj.text.charAt(ch)) && xDiff > 0 &&
            ch < lineObj.text.length && preparedMeasure.view.measure.heights.length > 1) {
          var charSize = measureCharPrepared(cm, preparedMeasure, ch, "right")
          if (innerOff <= charSize.bottom && innerOff >= charSize.top && Math.abs(x - charSize.right) < xDiff) {
            outside = false
            ch++
            xDiff = x - charSize.right
          }
        }
        while (isExtendingChar(lineObj.text.charAt(ch))) { ++ch }
        var pos = PosWithInfo(lineNo$$1, ch, outside, 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
  }
  
  // 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}
  }
  
  // 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
  }
  
  // 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) }
    })
  }
  
  // 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
  }
  
  // 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 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$$1 = doc.sel.ranges[i]
      if (range$$1.from().line >= cm.display.viewTo || range$$1.to().line < cm.display.viewFrom) { continue }
      var collapsed = range$$1.empty()
      if (collapsed || cm.options.showCursorWhenSelecting)
        { drawSelectionCursor(cm, range$$1.head, curFragment) }
      if (!collapsed)
        { drawSelectionRange(cm, range$$1, selFragment) }
    }
    return result
  }
  
  // Draws a cursor for the given range
  function drawSelectionCursor(cm, head, output) {
    var pos = cursorCoords(cm, 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$$1, 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;\n                             top: " + top + "px; width: " + (width == null ? rightSide - left : width) + "px;\n                             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$$1.from(), sTo = range$$1.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 () { return display.cursorDiv.style.visibility = (on = !on) ? "" : "hidden"; },
        cm.options.cursorBlinkRate) }
    else if (cm.options.cursorBlinkRate < 0)
      { display.cursorDiv.style.visibility = "hidden" }
  }
  
  function ensureFocus(cm) {
    if (!cm.state.focused) { cm.display.input.focus(); onFocus(cm) }
  }
  
  function delayBlurEvent(cm) {
    cm.state.delayingBlurEvent = true
    setTimeout(function () { if (cm.state.delayingBlurEvent) {
      cm.state.delayingBlurEvent = false
      onBlur(cm)
    } }, 100)
  }
  
  function onFocus(cm, e) {
    if (cm.state.delayingBlurEvent) { cm.state.delayingBlurEvent = false }
  
    if (cm.options.readOnly == "nocursor") { return }
    if (!cm.state.focused) {
      signal(cm, "focus", cm, e)
      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 () { return cm.display.input.reset(true); }, 20) } // Issue #1730
      }
      cm.display.input.receivedFocus()
    }
    restartBlink(cm)
  }
  function onBlur(cm, e) {
    if (cm.state.delayingBlurEvent) { return }
  
    if (cm.state.focused) {
      signal(cm, "blur", cm, e)
      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)
  }
  
  // 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) {
        if (view[i].gutter)
          { view[i].gutter.style.left = left }
        if (view[i].gutterBackground)
          { view[i].gutterBackground.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) + 1
      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
  }
  
  // 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 = void 0
      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.parentNode.offsetHeight } }
  }
  
  // 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)}
  }
  
  // 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;
  var 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 }
  
  function wheelEventDelta(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}
  }
  function wheelEventPixels(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
    var canScrollX = scroll.scrollWidth > scroll.clientWidth
    var canScrollY = scroll.scrollHeight > scroll.clientHeight
    if (!(dx && canScrollX || dy && canScrollY)) { 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 && canScrollY)
        { 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)))
      // Only prevent default scrolling if vertical scrolling is
      // actually possible. Otherwise, it causes vertical scroll
      // jitter on OSX trackpads when deltaX is small and deltaY
      // is large (issue #3579)
      if (!dy || (dy && canScrollY))
        { 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
      }
    }
  }
  
  // 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.checkedZeroWidth = 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.checkedZeroWidth && measure.clientHeight > 0) {
        if (sWidth == 0) { this.zeroWidthHack() }
        this.checkedZeroWidth = true
      }
  
      return {right: needsV ? sWidth : 0, bottom: needsH ? sWidth : 0}
    },
    setScrollLeft: function(pos) {
      if (this.horiz.scrollLeft != pos) { this.horiz.scrollLeft = pos }
      if (this.disableHoriz) { this.enableZeroWidthBar(this.horiz, this.disableHoriz) }
    },
    setScrollTop: function(pos) {
      if (this.vert.scrollTop != pos) { this.vert.scrollTop = pos }
      if (this.disableVert) { this.enableZeroWidthBar(this.vert, this.disableVert) }
    },
    zeroWidthHack: function() {
      var w = mac && !mac_geMountainLion ? "12px" : "18px"
      this.horiz.style.height = this.vert.style.width = w
      this.horiz.style.pointerEvents = this.vert.style.pointerEvents = "none"
      this.disableHoriz = new Delayed
      this.disableVert = new Delayed
    },
    enableZeroWidthBar: function(bar, delay) {
      bar.style.pointerEvents = "auto"
      function maybeDisable() {
        // To find out whether the scrollbar is still visible, we
        // check whether the element under the pixel in the bottom
        // left corner of the scrollbar box is the scrollbar box
        // itself (when the bar is still visible) or its filler child
        // (when the bar is hidden). If it is still visible, we keep
        // it enabled, if it's hidden, we disable pointer events.
        var box = bar.getBoundingClientRect()
        var elt$$1 = document.elementFromPoint(box.left + 1, box.bottom - 1)
        if (elt$$1 != bar) { bar.style.pointerEvents = "none" }
        else { delay.set(1000, maybeDisable) }
      }
      delay.set(1000, maybeDisable)
    },
    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)
  
  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"
    d.heightForcer.style.borderBottom = sizes.bottom + "px solid transparent"
  
    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 = "" }
  }
  
  var 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 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 () { return 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) }
  }
  
  // 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;\n                         top: " + (coords.top - display.viewOffset - paddingTop(cm.display)) + "px;\n                         height: " + (coords.bottom - coords.top + scrollGap(cm) + display.barHeight) + "px;\n                         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 }
    var coords
    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$$1 = cm.curOp.scrollToPos
    if (range$$1) {
      cm.curOp.scrollToPos = null
      var from = estimateCoords(cm, range$$1.from), to = estimateCoords(cm, range$$1.to)
      var sPos = calculateScrollPos(cm, Math.min(from.left, to.left),
                                    Math.min(from.top, to.top) - range$$1.margin,
                                    Math.max(from.right, to.right),
                                    Math.max(from.bottom, to.bottom) + range$$1.margin)
      cm.scrollTo(sPos.scrollLeft, sPos.scrollTop)
    }
  }
  
  // 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 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
      focus: false,
      id: ++nextOpId           // Unique ID
    }
    pushOperation(cm.curOp)
  }
  
  // Finish an operation, updating the display and signalling delayed events
  function endOperation(cm) {
    var op = cm.curOp
    finishOperation(op, function (group) {
      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$1 = 0; i$1 < ops.length; i$1++) // Write DOM (maybe)
      { endOperation_W1(ops[i$1]) }
    for (var i$2 = 0; i$2 < ops.length; i$2++) // Read DOM
      { endOperation_R2(ops[i$2]) }
    for (var i$3 = 0; i$3 < ops.length; i$3++) // Write DOM (maybe)
      { endOperation_W2(ops[i$3]) }
    for (var i$4 = 0; i$4 < ops.length; i$4++) // Read DOM
      { endOperation_finish(ops[i$4]) }
  }
  
  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(op.focus) }
  }
  
  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
    }
  
    var takeFocus = op.focus && op.focus == activeElt() && (!document.hasFocus || document.hasFocus())
    if (op.preparedSelection)
      { cm.display.input.showSelection(op.preparedSelection, takeFocus) }
    if (op.updatedDisplay || op.startHeight != cm.doc.height)
      { updateScrollbars(cm, op.barMeasure) }
    if (op.updatedDisplay)
      { setDocumentHeight(cm, op.barMeasure) }
  
    if (op.selectionChanged) { restartBlink(cm) }
  
    if (cm.state.focused && op.updateInput)
      { cm.display.input.reset(op.typing) }
    if (takeFocus) { ensureFocus(op.cm) }
  }
  
  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 - display.scroller.clientWidth, 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$1 = 0; i$1 < unhidden.length; ++i$1)
      { if (unhidden[i$1].lines.length) { signal(unhidden[i$1], "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) }
    }
  }
  
  // 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$1 = viewCuttingPoint(cm, from, from, -1)
      if (cut$1) {
        display.view = display.view.slice(0, cut$1.index)
        display.viewTo = cut$1.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
  }
  
  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} }
    var n = cm.display.viewFrom
    for (var i = 0; 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
  }
  
  // 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, tooLong = line.text.length > cm.options.maxHighlightLength
        var highlighted = highlightLine(cm, line, tooLong ? copyState(doc.mode, state) : 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 = tooLong ? state : copyState(doc.mode, state)
      } else {
        if (line.text.length <= cm.options.maxHighlightLength)
          { 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") }
    }) }
  }
  
  // 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() {
    var this$1 = this;
  
    for (var i = 0; i < this.events.length; i++)
      { signal.apply(null, this$1.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 = display.sizer.style.minHeight = 0
  
    if (different) {
      display.lastWrapHeight = update.wrapperHeight
      display.lastWrapWidth = update.wrapperWidth
      startWorker(cm, 400)
    }
  
    display.updateLineNumbers = null
  
    return true
  }
  
  function postUpdateDisplay(cm, update) {
    var viewport = update.viewport
  
    for (var first = true;; first = false) {
      if (!first || !cm.options.lineWrapping || update.oldDisplayWidth == displayWidth(cm)) {
        // 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)
      updateScrollbars(cm, barMeasure)
      setDocumentHeight(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)
      updateScrollbars(cm, barMeasure)
      setDocumentHeight(cm, barMeasure)
      update.finish()
    }
  }
  
  // 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) }
  }
  
  function updateGutterSpace(cm) {
    var width = cm.display.gutters.offsetWidth
    cm.display.sizer.style.marginLeft = width + "px"
  }
  
  function setDocumentHeight(cm, measure) {
    cm.display.sizer.style.minHeight = measure.docHeight + "px"
    cm.display.heightForcer.style.top = measure.docHeight + "px"
    cm.display.gutters.style.height = (measure.docHeight + cm.display.barHeight + scrollGap(cm)) + "px"
  }
  
  // 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)
    var i = 0
    for (; 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)
  }
  
  // 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)
    }
  }
  
  // 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) {
      var this$1 = this;
  
      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$1.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() {
      var this$1 = this;
  
      var out = []
      for (var i = 0; i < this.ranges.length; i++)
        { out[i] = new Range(copyPos(this$1.ranges[i].anchor), copyPos(this$1.ranges[i].head)) }
      return new Selection(out, this.primIndex)
    },
    somethingSelected: function() {
      var this$1 = this;
  
      for (var i = 0; i < this.ranges.length; i++)
        { if (!this$1.ranges[i].empty()) { return true } }
      return false
    },
    contains: function(pos, end) {
      var this$1 = this;
  
      if (!end) { end = pos }
      for (var i = 0; i < this.ranges.length; i++) {
        var range = this$1.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)
  }
  
  // Compute the position of the end of a change (its 'to' property
  // refers to the pre-change end).
  function changeEnd(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)
  }
  
  // Used to get the editor into a consistent state again when options change.
  
  function loadMode(cm) {
    cm.doc.mode = 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) }
  }
  
  // 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$$1) {
    function spansFor(n) {return markedSpans ? markedSpans[n] : null}
    function update(line, text, spans) {
      updateLine(line, text, spans, estimateHeight$$1)
      signalLater(line, "change", line, change)
    }
    function linesFor(start, end) {
      var result = []
      for (var i = start; i < end; ++i)
        { result.push(new Line(text[i], spansFor(i), estimateHeight$$1)) }
      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$1 = linesFor(1, text.length - 1)
        added$1.push(new Line(lastText + firstLine.text.slice(to.ch), lastSpans, estimateHeight$$1))
        update(firstLine, firstLine.text.slice(0, from.ch) + text[0], spansFor(0))
        doc.insert(from.line + 1, added$1)
      }
    } 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$2 = linesFor(1, text.length - 1)
      if (nlines > 1) { doc.remove(from.line + 1, nlines - 1) }
      doc.insert(from.line + 1, added$2)
    }
  
    signalLater(doc, "change", doc, change)
  }
  
  // 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)
  }
  
  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) { return 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, or 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
    var last
  
    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
      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 }
    var out
    for (var i = 0; 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 }
    var nw = []
    for (var i = 0; i < change.text.length; ++i)
      { nw.push(removeClearedSpans(found[i])) }
    return nw
  }
  
  // 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 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) {
    var copy = []
    for (var i = 0; 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 = void 0
        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
  }
  
  // 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) {
    var out = []
    for (var 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, options) {
    var obj = {
      ranges: sel.ranges,
      update: function(ranges) {
        var this$1 = this;
  
        this.ranges = []
        for (var i = 0; i < ranges.length; i++)
          { this$1.ranges[i] = new Range(clipPos(doc, ranges[i].anchor),
                                     clipPos(doc, ranges[i].head)) }
      },
      origin: options && options.origin
    }
    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, options) }
  
    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 old = sel.ranges.length == doc.sel.ranges.length && doc.sel.ranges[i]
      var newAnchor = skipAtomic(doc, range.anchor, old && old.anchor, bias, mayClear)
      var newHead = skipAtomic(doc, range.head, old && old.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
  }
  
  function skipAtomicInner(doc, pos, oldPos, dir, mayClear) {
    var line = getLine(doc, pos.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 <= pos.ch : sp.from < pos.ch)) &&
          (sp.to == null || (m.inclusiveRight ? sp.to >= pos.ch : sp.to > pos.ch))) {
        if (mayClear) {
          signal(m, "beforeCursorEnter")
          if (m.explicitlyCleared) {
            if (!line.markedSpans) { break }
            else {--i; continue}
          }
        }
        if (!m.atomic) { continue }
  
        if (oldPos) {
          var near = m.find(dir < 0 ? 1 : -1), diff = void 0
          if (dir < 0 ? m.inclusiveRight : m.inclusiveLeft)
            { near = movePos(doc, near, -dir, near && near.line == pos.line ? line : null) }
          if (near && near.line == pos.line && (diff = cmp(near, oldPos)) && (dir < 0 ? diff < 0 : diff > 0))
            { return skipAtomicInner(doc, near, pos, dir, mayClear) }
        }
  
        var far = m.find(dir < 0 ? -1 : 1)
        if (dir < 0 ? m.inclusiveLeft : m.inclusiveRight)
          { far = movePos(doc, far, dir, far.line == pos.line ? line : null) }
        return far ? skipAtomicInner(doc, far, pos, dir, mayClear) : null
      }
    } }
    return pos
  }
  
  // Ensure a given position is not inside an atomic range.
  function skipAtomic(doc, pos, oldPos, bias, mayClear) {
    var dir = bias || 1
    var found = skipAtomicInner(doc, pos, oldPos, dir, mayClear) ||
        (!mayClear && skipAtomicInner(doc, pos, oldPos, dir, true)) ||
        skipAtomicInner(doc, pos, oldPos, -dir, mayClear) ||
        (!mayClear && skipAtomicInner(doc, pos, oldPos, -dir, true))
    if (!found) {
      doc.cantEdit = true
      return Pos(doc.first, 0)
    }
    return found
  }
  
  function movePos(doc, pos, dir, line) {
    if (dir < 0 && pos.ch == 0) {
      if (pos.line > doc.first) { return clipPos(doc, Pos(pos.line - 1)) }
      else { return null }
    } else if (dir > 0 && pos.ch == (line || getLine(doc, pos.line)).text.length) {
      if (pos.line < doc.first + doc.size - 1) { return Pos(pos.line + 1, 0) }
      else { return null }
    } else {
      return new Pos(pos.line, pos.ch + dir)
    }
  }
  
  function selectAll(cm) {
    cm.setSelection(Pos(cm.firstLine(), 0), Pos(cm.lastLine()), sel_dontScroll)
  }
  
  // UPDATING
  
  // 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 () { return obj.canceled = true; }
    }
    if (update) { obj.update = function (from, to, text, origin) {
      if (from) { obj.from = clipPos(doc, from) }
      if (to) { obj.to = clipPos(doc, to) }
      if (text) { obj.text = text }
      if (origin !== undefined) { obj.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 && !allowSelectionOnly) { 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)
    var i = 0
    for (; 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")
  
    var loop = function ( 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))
      })
    };
  
    for (var i$1 = event.changes.length - 1; i$1 >= 0; --i$1) {
      var returned = loop( i$1 );
  
      if ( returned ) return returned.v;
    }
  }
  
  // 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 = doc.splitLines(code) }
    makeChange(doc, {from: from, to: to, text: code, origin: origin})
  }
  
  // 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$1 = 0; j$1 < sub.changes.length; ++j$1) {
        var cur = sub.changes[j$1]
        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)
  }
  
  // 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
  }
  
  // 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) {
    var this$1 = this;
  
    this.lines = lines
    this.parent = null
    var height = 0
    for (var i = 0; i < lines.length; ++i) {
      lines[i].parent = this$1
      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) {
      var this$1 = this;
  
      for (var i = at, e = at + n; i < e; ++i) {
        var line = this$1.lines[i]
        this$1.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) {
      var this$1 = this;
  
      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$1 }
    },
    // Used to iterate over a part of the tree.
    iterN: function(at, n, op) {
      var this$1 = this;
  
      for (var e = at + n; at < e; ++at)
        { if (op(this$1.lines[at])) { return true } }
    }
  }
  
  function BranchChunk(children) {
    var this$1 = this;
  
    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$1
    }
    this.size = size
    this.height = height
    this.parent = null
  }
  
  BranchChunk.prototype = {
    chunkSize: function() { return this.size },
    removeInner: function(at, n) {
      var this$1 = this;
  
      this.size -= n
      for (var i = 0; i < this.children.length; ++i) {
        var child = this$1.children[i], sz = child.chunkSize()
        if (at < sz) {
          var rm = Math.min(n, sz - at), oldHeight = child.height
          child.removeInner(at, rm)
          this$1.height -= oldHeight - child.height
          if (sz == rm) { this$1.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) {
      var this$1 = this;
  
      for (var i = 0; i < this.children.length; ++i) { this$1.children[i].collapse(lines) }
    },
    insertInner: function(at, lines, height) {
      var this$1 = this;
  
      this.size += lines.length
      this.height += height
      for (var i = 0; i < this.children.length; ++i) {
        var child = this$1.children[i], sz = child.chunkSize()
        if (at <= sz) {
          child.insertInner(at, lines, height)
          if (child.lines && child.lines.length > 50) {
            // To avoid memory thrashing when child.lines is huge (e.g. first view of a large file), it's never spliced.
            // Instead, small slices are taken. They're taken in order because sequential memory accesses are fastest.
            var remaining = child.lines.length % 25 + 25
            for (var pos = remaining; pos < child.lines.length;) {
              var leaf = new LeafChunk(child.lines.slice(pos, pos += 25))
              child.height -= leaf.height
              this$1.children.splice(++i, 0, leaf)
              leaf.parent = this$1
            }
            child.lines = child.lines.slice(0, remaining)
            this$1.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) {
      var this$1 = this;
  
      for (var i = 0; i < this.children.length; ++i) {
        var child = this$1.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 }
      }
    }
  }
  
  // Line widgets are block elements displayed above or below a line.
  
  function LineWidget(doc, node, options) {
    var this$1 = this;
  
    if (options) { for (var opt in options) { if (options.hasOwnProperty(opt))
      { this$1[opt] = options[opt] } } }
    this.doc = doc
    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 this$1 = this;
  
    var cm = this.doc.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$1) { ws.splice(i--, 1) } }
    if (!ws.length) { line.widgets = null }
    var height = widgetHeight(this)
    updateLineHeight(line, Math.max(0, line.height - height))
    if (cm) { runInOp(cm, function () {
      adjustScrollWhenAboveVisible(cm, line, -height)
      regLineChange(cm, no, "widget")
    }) }
  }
  LineWidget.prototype.changed = function() {
    var oldH = this.height, cm = this.doc.cm, line = this.line
    this.height = null
    var diff = widgetHeight(this) - oldH
    if (!diff) { return }
    updateLineHeight(line, line.height + diff)
    if (cm) { runInOp(cm, function () {
      cm.curOp.forceUpdate = true
      adjustScrollWhenAboveVisible(cm, line, diff)
    }) }
  }
  
  function addLineWidget(doc, handle, node, options) {
    var widget = new LineWidget(doc, node, options)
    var cm = doc.cm
    if (cm && widget.noHScroll) { cm.display.alignWidgets = true }
    changeLine(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 (cm && !lineIsHidden(doc, line)) {
        var aboveVisible = heightAtLine(line) < doc.scrollTop
        updateLineHeight(line, line.height + widgetHeight(widget))
        if (aboveVisible) { addToScrollPos(cm, null, widget.height) }
        cm.curOp.forceUpdate = true
      }
      return true
    })
    return widget
  }
  
  // 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.
  
  // 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
  
  function TextMarker(doc, type) {
    this.lines = []
    this.type = type
    this.doc = doc
    this.id = ++nextMarkerId
  }
  eventMixin(TextMarker)
  
  // Clear the marker.
  TextMarker.prototype.clear = function() {
    var this$1 = this;
  
    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$1.lines[i]
      var span = getMarkedSpanFor(line.markedSpans, this$1)
      if (cm && !this$1.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$1.collapsed && !lineIsHidden(this$1.doc, line) && cm)
        { updateLineHeight(line, textHeight(cm.display)) }
    }
    if (cm && this.collapsed && !cm.options.lineWrapping) { for (var i$1 = 0; i$1 < this.lines.length; ++i$1) {
      var visual = visualLine(this$1.lines[i$1]), 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) {
    var this$1 = this;
  
    if (side == null && this.type == "bookmark") { side = 1 }
    var from, to
    for (var i = 0; i < this.lines.length; ++i) {
      var line = this$1.lines[i]
      var span = getMarkedSpanFor(line.markedSpans, this$1)
      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)
    }
  }
  
  // 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") }
      seeCollapsedSpans()
    }
  
    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 () { return marker.clear(); }) }
  
    if (marker.readOnly) {
      seeReadOnlySpans()
      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.
  function SharedTextMarker(markers, primary) {
    var this$1 = this;
  
    this.markers = markers
    this.primary = primary
    for (var i = 0; i < markers.length; ++i)
      { markers[i].parent = this$1 }
  }
  eventMixin(SharedTextMarker)
  
  SharedTextMarker.prototype.clear = function() {
    var this$1 = this;
  
    if (this.explicitlyCleared) { return }
    this.explicitlyCleared = true
    for (var i = 0; i < this.markers.length; ++i)
      { this$1.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) {
    var loop = function ( i ) {
      var marker = markers[i], linked = [marker.primary.doc]
      linkedDocs(marker.primary.doc, function (d) { return 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)
        }
      }
    };
  
    for (var i = 0; i < markers.length; i++) loop( i );
  }
  
  var nextDocId = 0
  var Doc = function(text, mode, firstLine, lineSep) {
    if (!(this instanceof Doc)) { return new Doc(text, mode, firstLine, lineSep) }
    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
    this.lineSep = lineSep
    this.extend = false
  
    if (typeof text == "string") { text = this.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 || this.lineSeparator())
    },
    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: this.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 || this.lineSeparator())
    },
  
    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$$1 = this.sel.primary(), pos
      if (start == null || start == "head") { pos = range$$1.head }
      else if (start == "anchor") { pos = range$$1.anchor }
      else if (start == "end" || start == "to" || start === false) { pos = range$$1.to() }
      else { pos = range$$1.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) {
      var heads = map(this.sel.ranges, f)
      extendSelections(this, clipPosArray(this, heads), options)
    }),
    setSelections: docMethodOp(function(ranges, primary, options) {
      var this$1 = this;
  
      if (!ranges.length) { return }
      var out = []
      for (var i = 0; i < ranges.length; i++)
        { out[i] = new Range(clipPos(this$1, ranges[i].anchor),
                           clipPos(this$1, 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 this$1 = this;
  
      var ranges = this.sel.ranges, lines
      for (var i = 0; i < ranges.length; i++) {
        var sel = getBetween(this$1, ranges[i].from(), ranges[i].to())
        lines = lines ? lines.concat(sel) : sel
      }
      if (lineSep === false) { return lines }
      else { return lines.join(lineSep || this.lineSeparator()) }
    },
    getSelections: function(lineSep) {
      var this$1 = this;
  
      var parts = [], ranges = this.sel.ranges
      for (var i = 0; i < ranges.length; i++) {
        var sel = getBetween(this$1, ranges[i].from(), ranges[i].to())
        if (lineSep !== false) { sel = sel.join(lineSep || this$1.lineSeparator()) }
        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 this$1 = this;
  
      var changes = [], sel = this.sel
      for (var i = 0; i < sel.ranges.length; i++) {
        var range$$1 = sel.ranges[i]
        changes[i] = {from: range$$1.from(), to: range$$1.to(), text: this$1.splitLines(code[i]), origin: origin}
      }
      var newSel = collapse && collapse != "end" && computeReplacedSel(this, changes, collapse)
      for (var i$1 = changes.length - 1; i$1 >= 0; i$1--)
        { makeChange(this$1, changes[i$1]) }
      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$1 = 0; i$1 < hist.undone.length; i$1++) { if (!hist.undone[i$1].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
      })
    }),
  
    addLineWidget: docMethodOp(function(handle, node, options) {
      return addLineWidget(this, handle, node, options)
    }),
    removeLineWidget: function(widget) { widget.clear() },
  
    markText: function(from, to, options) {
      return markText(this, clipPos(this, from), clipPos(this, to), options, options && options.type || "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,
                      handleMouseEvents: options && options.handleMouseEvents}
      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$$1 = from.line
      this.iter(from.line, to.line + 1, function (line) {
        var spans = line.markedSpans
        if (spans) { for (var i = 0; i < spans.length; i++) {
          var span = spans[i]
          if (!(span.to != null && lineNo$$1 == from.line && from.ch >= span.to ||
                span.from == null && lineNo$$1 != from.line ||
                span.from != null && lineNo$$1 == to.line && span.from >= to.ch) &&
              (!filter || filter(span.marker)))
            { found.push(span.marker.parent || span.marker) }
        } }
        ++lineNo$$1
      })
      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$$1 = this.first, sepSize = this.lineSeparator().length
      this.iter(function (line) {
        var sz = line.text.length + sepSize
        if (sz > off) { ch = off; return true }
        off -= sz
        ++lineNo$$1
      })
      return clipPos(this, Pos(lineNo$$1, ch))
    },
    indexFromPos: function (coords) {
      coords = clipPos(this, coords)
      var index = coords.ch
      if (coords.line < this.first || coords.ch < 0) { return 0 }
      var sepSize = this.lineSeparator().length
      this.iter(this.first, coords.line, function (line) { // iter aborts when callback returns a truthy value
        index += line.text.length + sepSize
      })
      return index
    },
  
    copy: function(copyHistory) {
      var doc = new Doc(getLines(this, this.first, this.first + this.size),
                        this.modeOption, this.first, this.lineSep)
      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, this.lineSep)
      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) {
      var this$1 = this;
  
      if (other instanceof CodeMirror$1) { other = other.doc }
      if (this.linked) { for (var i = 0; i < this.linked.length; ++i) {
        var link = this$1.linked[i]
        if (link.doc != other) { continue }
        this$1.linked.splice(i, 1)
        other.unlinkDoc(this$1)
        detachSharedMarkers(findSharedMarkers(this$1))
        break
      } }
      // If the histories were shared, split them again
      if (other.history == this.history) {
        var splitIds = [other.id]
        linkedDocs(other, function (doc) { return 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},
  
    splitLines: function(str) {
      if (this.lineSep) { return str.split(this.lineSep) }
      return splitLinesAuto(str)
    },
    lineSeparator: function() { return this.lineSep || "\n" }
  })
  
  // Public alias.
  Doc.prototype.eachLine = Doc.prototype.iter
  
  // 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
    clearDragCursor(cm)
    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 || cm.isReadOnly()) { 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) {
        if (cm.options.allowDropFileTypes &&
            indexOf(cm.options.allowDropFileTypes, file.type) == -1)
          { return }
  
        var reader = new FileReader
        reader.onload = operation(cm, function () {
          var content = reader.result
          if (/[\x00-\x08\x0e-\x1f]{2}/.test(content)) { content = "" }
          text[i] = content
          if (++read == n) {
            pos = clipPos(cm.doc, pos)
            var change = {from: pos, to: pos,
                          text: cm.doc.splitLines(text.join(cm.doc.lineSeparator())),
                          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 () { return cm.display.input.focus(); }, 20)
        return
      }
      try {
        var text$1 = e.dataTransfer.getData("Text")
        if (text$1) {
          var selected
          if (cm.state.draggingText && !cm.state.draggingText.copy)
            { selected = cm.listSelections() }
          setSelectionNoUndo(cm.doc, simpleSelection(pos, pos))
          if (selected) { for (var i$1 = 0; i$1 < selected.length; ++i$1)
            { replaceRange(cm.doc, "", selected[i$1].anchor, selected[i$1].head, "drag") } }
          cm.replaceSelection(text$1, "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())
    e.dataTransfer.effectAllowed = "copyMove"
  
    // 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) }
    }
  }
  
  function onDragOver(cm, e) {
    var pos = posFromMouse(cm, e)
    if (!pos) { return }
    var frag = document.createDocumentFragment()
    drawSelectionCursor(cm, pos, frag)
    if (!cm.display.dragCursor) {
      cm.display.dragCursor = elt("div", null, "CodeMirror-cursors CodeMirror-dragcursors")
      cm.display.lineSpace.insertBefore(cm.display.dragCursor, cm.display.cursorDiv)
    }
    removeChildrenAndAdd(cm.display.dragCursor, frag)
  }
  
  function clearDragCursor(cm) {
    if (cm.display.dragCursor) {
      cm.display.lineSpace.removeChild(cm.display.dragCursor)
      cm.display.dragCursor = null
    }
  }
  
  // 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 () { return forEachCodeMirror(onBlur); })
  }
  // 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()
  }
  
  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",
    106: "*", 107: "=", 109: "-", 110: ".", 111: "/", 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"
  }
  
  // Number keys
  for (var i = 0; i < 10; i++) { keyNames[i + 48] = keyNames[i + 96] = String(i) }
  // Alphabetic keys
  for (var i$1 = 65; i$1 <= 90; i$1++) { keyNames[i$1] = String.fromCharCode(i$1) }
  // Function keys
  for (var i$2 = 1; i$2 <= 12; i$2++) { keyNames[i$2 + 111] = keyNames[i$2 + 63235] = "F" + i$2 }
  
  var 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",
    "Ctrl-O": "openLine"
  }
  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.
  function normalizeKeyMap(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 = void 0, name = void 0
        if (i == keys.length - 1) {
          name = keys.join(" ")
          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
  }
  
  function lookupKey(key, map$$1, handle, context) {
    map$$1 = getKeyMap(map$$1)
    var found = map$$1.call ? map$$1.call(key, context) : map$$1[key]
    if (found === false) { return "nothing" }
    if (found === "...") { return "multi" }
    if (found != null && handle(found)) { return "handled" }
  
    if (map$$1.fallthrough) {
      if (Object.prototype.toString.call(map$$1.fallthrough) != "[object Array]")
        { return lookupKey(key, map$$1.fallthrough, handle, context) }
      for (var i = 0; i < map$$1.fallthrough.length; i++) {
        var result = lookupKey(key, map$$1.fallthrough[i], handle, context)
        if (result) { return result }
      }
    }
  }
  
  // Modifier key presses don't count as 'real' key presses for the
  // purpose of keymap fallthrough.
  function isModifierKey(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.
  function keyName(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
  }
  
  // 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)
    })
  }
  
  // Commands are parameter-less actions that can be performed on an
  // editor, mostly used for keybindings.
  var commands = {
    selectAll: selectAll,
    singleSelection: function (cm) { return cm.setSelection(cm.getCursor("anchor"), cm.getCursor("head"), sel_dontScroll); },
    killLine: function (cm) { return 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) { return deleteNearSelection(cm, function (range) { return ({
      from: Pos(range.from().line, 0),
      to: clipPos(cm.doc, Pos(range.to().line + 1, 0))
    }); }); },
    delLineLeft: function (cm) { return deleteNearSelection(cm, function (range) { return ({
      from: Pos(range.from().line, 0), to: range.from()
    }); }); },
    delWrappedLineLeft: function (cm) { return 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) { return 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) { return cm.undo(); },
    redo: function (cm) { return cm.redo(); },
    undoSelection: function (cm) { return cm.undoSelection(); },
    redoSelection: function (cm) { return cm.redoSelection(); },
    goDocStart: function (cm) { return cm.extendSelection(Pos(cm.firstLine(), 0)); },
    goDocEnd: function (cm) { return cm.extendSelection(Pos(cm.lastLine())); },
    goLineStart: function (cm) { return cm.extendSelectionsBy(function (range) { return lineStart(cm, range.head.line); },
      {origin: "+move", bias: 1}
    ); },
    goLineStartSmart: function (cm) { return cm.extendSelectionsBy(function (range) { return lineStartSmart(cm, range.head); },
      {origin: "+move", bias: 1}
    ); },
    goLineEnd: function (cm) { return cm.extendSelectionsBy(function (range) { return lineEnd(cm, range.head.line); },
      {origin: "+move", bias: -1}
    ); },
    goLineRight: function (cm) { return 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) { return 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) { return 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) { return cm.moveV(-1, "line"); },
    goLineDown: function (cm) { return cm.moveV(1, "line"); },
    goPageUp: function (cm) { return cm.moveV(-1, "page"); },
    goPageDown: function (cm) { return cm.moveV(1, "page"); },
    goCharLeft: function (cm) { return cm.moveH(-1, "char"); },
    goCharRight: function (cm) { return cm.moveH(1, "char"); },
    goColumnLeft: function (cm) { return cm.moveH(-1, "column"); },
    goColumnRight: function (cm) { return cm.moveH(1, "column"); },
    goWordLeft: function (cm) { return cm.moveH(-1, "word"); },
    goGroupRight: function (cm) { return cm.moveH(1, "group"); },
    goGroupLeft: function (cm) { return cm.moveH(-1, "group"); },
    goWordRight: function (cm) { return cm.moveH(1, "word"); },
    delCharBefore: function (cm) { return cm.deleteH(-1, "char"); },
    delCharAfter: function (cm) { return cm.deleteH(1, "char"); },
    delWordBefore: function (cm) { return cm.deleteH(-1, "word"); },
    delWordAfter: function (cm) { return cm.deleteH(1, "word"); },
    delGroupBefore: function (cm) { return cm.deleteH(-1, "group"); },
    delGroupAfter: function (cm) { return cm.deleteH(1, "group"); },
    indentAuto: function (cm) { return cm.indentSelection("smart"); },
    indentMore: function (cm) { return cm.indentSelection("add"); },
    indentLess: function (cm) { return cm.indentSelection("subtract"); },
    insertTab: function (cm) { return 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(spaceStr(tabSize - col % tabSize))
      }
      cm.replaceSelections(spaces)
    },
    defaultTab: function (cm) {
      if (cm.somethingSelected()) { cm.indentSelection("add") }
      else { cm.execCommand("insertTab") }
    },
    // Swap the two chars left and right of each selection's head.
    // Move cursor behind the two swapped characters afterwards.
    //
    // Doesn't consider line feeds a character.
    // Doesn't scan more than one line above to find a character.
    // Doesn't do anything on an empty line.
    // Doesn't do anything with non-empty selections.
    transposeChars: function (cm) { return runInOp(cm, function () {
      var ranges = cm.listSelections(), newSel = []
      for (var i = 0; i < ranges.length; i++) {
        if (!ranges[i].empty()) { continue }
        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) {
              cur = new Pos(cur.line, 1)
              cm.replaceRange(line.charAt(0) + cm.doc.lineSeparator() +
                              prev.charAt(prev.length - 1),
                              Pos(cur.line - 1, prev.length - 1), cur, "+transpose")
            }
          }
        }
        newSel.push(new Range(cur, cur))
      }
      cm.setSelections(newSel)
    }); },
    newlineAndIndent: function (cm) { return runInOp(cm, function () {
      var sels = cm.listSelections()
      for (var i = sels.length - 1; i >= 0; i--)
        { cm.replaceRange(cm.doc.lineSeparator(), sels[i].anchor, sels[i].head, "+input") }
      sels = cm.listSelections()
      for (var i$1 = 0; i$1 < sels.length; i$1++)
        { cm.indentLine(sels[i$1].from().line, null, true) }
      ensureCursorVisible(cm)
    }); },
    openLine: function (cm) { return cm.replaceSelection("\n", "start"); },
    toggleOverwrite: function (cm) { return cm.toggleOverwrite(); }
  }
  
  
  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
  }
  
  // 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 (cm.isReadOnly()) { 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
    cm.curOp.focus = activeElt()
    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)
    // Some browsers fire keypress events for backspace
    if (ch == "\x08") { return }
    if (handleCharBinding(cm, e, ch)) { return }
    cm.display.input.onKeyPress(e)
  }
  
  // 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 (signalDOMEvent(cm, e) || display.activeTouch && display.input.supportsTouch()) { 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 () { return display.scroller.draggable = true; }, 100)
      }
      return
    }
    if (clickInGutter(cm, e)) { return }
    var start = posFromMouse(cm, e)
    window.focus()
  
    switch (e_button(e)) {
    case 1:
      // #3261: make sure, that we're not starting a second selection
      if (cm.state.selectingText)
        { cm.state.selectingText(e) }
      else 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 () { return display.input.focus(); }, 20)
      e_preventDefault(e)
      break
    case 3:
      if (captureRightClick) { onContextMenu(cm, e) }
      else { delayBlurEvent(cm) }
      break
    }
  }
  
  var lastClick;
  var lastDoubleClick
  function leftButtonDown(cm, e, start) {
    if (ie) { setTimeout(bind(ensureFocus, cm), 0) }
    else { cm.curOp.focus = activeElt() }
  
    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 && !cm.isReadOnly() &&
        type == "single" && (contained = sel.contains(start)) > -1 &&
        (cmp((contained = sel.ranges[contained]).from(), start) < 0 || start.xRel > 0) &&
        (cmp(contained.to(), start) > 0 || start.xRel < 0))
      { 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, startTime = +new Date
    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 && +new Date - 200 < startTime)
          { extendSelection(cm.doc, start) }
        // Work around unexplainable focus problem in IE9 (#2127) and Chrome (#3081)
        if (webkit || ie && ie_version == 9)
          { setTimeout(function () {document.body.focus(); display.input.focus()}, 20) }
        else
          { display.input.focus() }
      }
    })
    // Let the drag handler handle this.
    if (webkit) { display.scroller.draggable = true }
    cm.state.draggingText = dragEnd
    dragEnd.copy = mac ? e.altKey : e.ctrlKey
    // 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()
      ourIndex = doc.sel.primIndex
    }
  
    if (chromeOS ? e.shiftKey && e.metaKey : 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" && !e.shiftKey) {
      setSelection(doc, normalizeSelection(ranges.slice(0, ourIndex).concat(ranges.slice(ourIndex + 1)), 0),
                   {scroll: false, origin: "*mouse"})
      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") {
          var range$$1
          if (type == "double")
            { range$$1 = cm.findWordAt(pos) }
          else
            { range$$1 = new Range(Pos(pos.line, 0), clipPos(doc, Pos(pos.line + 1, 0))) }
          if (cmp(range$$1.anchor, anchor) > 0) {
            head = range$$1.head
            anchor = minPos(oldRange.from(), range$$1.anchor)
          } else {
            head = range$$1.anchor
            anchor = maxPos(oldRange.to(), range$$1.head)
          }
        }
        var ranges$1 = startSel.ranges.slice(0)
        ranges$1[ourIndex] = new Range(clipPos(doc, anchor), head)
        setSelection(doc, normalizeSelection(ranges$1, 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) {
        cm.curOp.focus = activeElt()
        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) {
      cm.state.selectingText = false
      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)
    cm.state.selectingText = up
    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) {
    var mX, mY
    try { 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]
        signal(cm, type, cm, line, gutter, e)
        return e_defaultPrevented(e)
      }
    }
  }
  
  function clickInGutter(cm, e) {
    return gutterEvent(cm, e, "gutterClick", true)
  }
  
  // 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 }
    if (signalDOMEvent(cm, e, "contextmenu")) { return }
    cm.display.input.onContextMenu(e)
  }
  
  function contextMenuInGutter(cm, e) {
    if (!hasHandler(cm, "gutterContextMenu")) { return false }
    return gutterEvent(cm, e, "gutterContextMenu", false)
  }
  
  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)
  }
  
  var Init = {toString: function(){return "CodeMirror.Init"}}
  
  var defaults = {}
  var optionHandlers = {}
  
  function defineOptions(CodeMirror) {
    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 }
    }
  
    CodeMirror.defineOption = option
  
    // Passed to option handlers when there is no old value.
    CodeMirror.Init = 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) { return 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("lineSeparator", null, function (cm, val) {
      cm.doc.lineSep = val
      if (!val) { return }
      var newBreaks = [], lineNo = cm.doc.first
      cm.doc.iter(function (line) {
        for (var pos = 0;;) {
          var found = line.text.indexOf(val, pos)
          if (found == -1) { break }
          pos = found + val.length
          newBreaks.push(Pos(lineNo, found))
        }
        lineNo++
      })
      for (var i = newBreaks.length - 1; i >= 0; i--)
        { replaceRange(cm.doc, val, newBreaks[i], Pos(newBreaks[i].line, newBreaks[i].ch + val.length)) }
    })
    option("specialChars", /[\u0000-\u001f\u007f\u00ad\u200b-\u200f\u2028\u2029\ufeff]/g, function (cm, val, old) {
      cm.state.specialChars = new RegExp(val.source + (val.test("\t") ? "" : "|\t"), "g")
      if (old != Init) { cm.refresh() }
    })
    option("specialCharPlaceholder", defaultSpecialCharPlaceholder, function (cm) { return 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("spellcheck", false, function (cm, val) { return cm.getInputField().spellcheck = val; }, 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 != 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) { return 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("lineWiseCopyCut", 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
      }
      cm.display.input.readOnlyChanged(val)
    })
    option("disableInput", false, function (cm, val) {if (!val) { cm.display.input.reset() }}, true)
    option("dragDrop", true, dragDropChanged)
    option("allowDropFileTypes", null)
  
    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) { return cm.doc.history.undoDepth = val; })
    option("historyEventDelay", 1250)
    option("viewportMargin", 10, function (cm) { return 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) { return cm.display.input.getField().tabIndex = val || ""; })
    option("autofocus", null)
  }
  
  function guttersChanged(cm) {
    updateGutters(cm)
    regChange(cm)
    setTimeout(function () { return alignHorizontally(cm); }, 20)
  }
  
  function dragDropChanged(cm, value, old) {
    var wasOn = old && old != Init
    if (!value != !wasOn) {
      var funcs = cm.display.dragFunctions
      var toggle = value ? on : off
      toggle(cm.display.scroller, "dragstart", funcs.start)
      toggle(cm.display.scroller, "dragenter", funcs.enter)
      toggle(cm.display.scroller, "dragover", funcs.over)
      toggle(cm.display.scroller, "dragleave", funcs.leave)
      toggle(cm.display.scroller, "drop", funcs.drop)
    }
  }
  
  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 () { return updateScrollbars(cm); }, 100)
  }
  
  // A CodeMirror instance represents an editor. This is the object
  // that user code is usually dealing with.
  
  function CodeMirror$1(place, options) {
    var this$1 = this;
  
    if (!(this instanceof CodeMirror$1)) { return new CodeMirror$1(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, null, options.lineSeparator) }
    this.doc = doc
  
    var input = new CodeMirror$1.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,
      delayingBlurEvent: 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
      selectingText: false,
      draggingText: false,
      highlight: new Delayed(), // stores highlight worker timeout
      keySeq: null,  // Unfinished key sequence
      specialChars: null
    }
  
    // Override magic textarea content restore that IE sometimes does
    // on our hidden textarea on reload
    if (ie && ie_version < 11) { setTimeout(function () { return this$1.display.input.reset(true); }, 20) }
  
    registerEventHandlers(this)
    ensureGlobalHandlers()
  
    startOperation(this)
    this.curOp.forceUpdate = true
    attachDoc(this, doc)
  
    if ((options.autofocus && !mobile) || this.hasFocus())
      { setTimeout(bind(onFocus, this), 20) }
    else
      { onBlur(this) }
  
    for (var opt in optionHandlers) { if (optionHandlers.hasOwnProperty(opt))
      { optionHandlers[opt](this$1, options[opt], Init) } }
    maybeUpdateLineNumberWidth(this)
    if (options.finishInit) { options.finishInit(this) }
    for (var i = 0; i < initHooks.length; ++i) { initHooks[i](this$1) }
    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" }
  }
  
  // The default configuration options.
  CodeMirror$1.defaults = defaults
  // Functions to run when options are changed.
  CodeMirror$1.optionHandlers = optionHandlers
  
  // 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) { return 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) { return 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 () { return 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 (!signalDOMEvent(cm, e) && !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) { return onScrollWheel(cm, e); })
    on(d.scroller, "DOMMouseScroll", function (e) { return onScrollWheel(cm, e); })
  
    // Prevent wrapper from ever scrolling
    on(d.wrapper, "scroll", function () { return d.wrapper.scrollTop = d.wrapper.scrollLeft = 0; })
  
    d.dragFunctions = {
      enter: function (e) {if (!signalDOMEvent(cm, e)) { e_stop(e) }},
      over: function (e) {if (!signalDOMEvent(cm, e)) { onDragOver(cm, e); e_stop(e) }},
      start: function (e) { return onDragStart(cm, e); },
      drop: operation(cm, onDrop),
      leave: function (e) {if (!signalDOMEvent(cm, e)) { clearDragCursor(cm) }}
    }
  
    var inp = d.input.getField()
    on(inp, "keyup", function (e) { return onKeyUp.call(cm, e); })
    on(inp, "keydown", operation(cm, onKeyDown))
    on(inp, "keypress", operation(cm, onKeyPress))
    on(inp, "focus", function (e) { return onFocus(cm, e); })
    on(inp, "blur", function (e) { return onBlur(cm, e); })
  }
  
  var initHooks = []
  CodeMirror$1.defineInitHook = function (f) { return initHooks.push(f); }
  
  // 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")
      line.stateAfter = null
      return true
    } 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$1 = 0; i$1 < doc.sel.ranges.length; i$1++) {
        var range = doc.sel.ranges[i$1]
        if (range.head.line == n && range.head.ch < curSpaceString.length) {
          var pos$1 = Pos(n, curSpaceString.length)
          replaceOneSelection(doc, i$1, new Range(pos$1, pos$1))
          break
        }
      }
    }
  }
  
  // This will be set to a {lineWise: bool, text: [string]} object, so
  // that, when pasting, we know what kind of selections the copied
  // text was made out of.
  var lastCopied = null
  
  function setLastCopied(newLastCopied) {
    lastCopied = newLastCopied
  }
  
  function applyTextInput(cm, inserted, deleted, sel, origin) {
    var doc = cm.doc
    cm.display.shift = false
    if (!sel) { sel = doc.sel }
  
    var paste = cm.state.pasteIncoming || origin == "paste"
    var textLines = splitLinesAuto(inserted), multiPaste = null
    // When pasing N lines into N selections, insert one line per selection
    if (paste && sel.ranges.length > 1) {
      if (lastCopied && lastCopied.text.join("\n") == inserted) {
        if (sel.ranges.length % lastCopied.text.length == 0) {
          multiPaste = []
          for (var i = 0; i < lastCopied.text.length; i++)
            { multiPaste.push(doc.splitLines(lastCopied.text[i])) }
        }
      } else if (textLines.length == sel.ranges.length) {
        multiPaste = map(textLines, function (l) { return [l]; })
      }
    }
  
    var updateInput
    // Normal behavior is to insert the new text into every selection
    for (var i$1 = sel.ranges.length - 1; i$1 >= 0; i$1--) {
      var range$$1 = sel.ranges[i$1]
      var from = range$$1.from(), to = range$$1.to()
      if (range$$1.empty()) {
        if (deleted && deleted > 0) // Handle deletion
          { from = Pos(from.line, from.ch - deleted) }
        else if (cm.state.overwrite && !paste) // Handle overwrite
          { to = Pos(to.line, Math.min(getLine(doc, to.line).text.length, to.ch + lst(textLines).length)) }
        else if (lastCopied && lastCopied.lineWise && lastCopied.text.join("\n") == inserted)
          { from = to = Pos(from.line, 0) }
      }
      updateInput = cm.curOp.updateInput
      var changeEvent = {from: from, to: to, text: multiPaste ? multiPaste[i$1 % multiPaste.length] : textLines,
                         origin: origin || (paste ? "paste" : cm.state.cutIncoming ? "cut" : "+input")}
      makeChange(cm.doc, changeEvent)
      signalLater(cm, "inputRead", cm, changeEvent)
    }
    if (inserted && !paste)
      { triggerElectric(cm, inserted) }
  
    ensureCursorVisible(cm)
    cm.curOp.updateInput = updateInput
    cm.curOp.typing = true
    cm.state.pasteIncoming = cm.state.cutIncoming = false
  }
  
  function handlePaste(e, cm) {
    var pasted = e.clipboardData && e.clipboardData.getData("Text")
    if (pasted) {
      e.preventDefault()
      if (!cm.isReadOnly() && !cm.options.disableInput)
        { runInOp(cm, function () { return applyTextInput(cm, pasted, 0, null, "paste"); }) }
      return true
    }
  }
  
  function triggerElectric(cm, inserted) {
    // When an 'electric' character is inserted, immediately trigger a reindent
    if (!cm.options.electricChars || !cm.options.smartIndent) { return }
    var sel = cm.doc.sel
  
    for (var i = sel.ranges.length - 1; i >= 0; i--) {
      var range$$1 = sel.ranges[i]
      if (range$$1.head.ch > 100 || (i && sel.ranges[i - 1].head.line == range$$1.head.line)) { continue }
      var mode = cm.getModeAt(range$$1.head)
      var indented = false
      if (mode.electricChars) {
        for (var j = 0; j < mode.electricChars.length; j++)
          { if (inserted.indexOf(mode.electricChars.charAt(j)) > -1) {
            indented = indentLine(cm, range$$1.head.line, "smart")
            break
          } }
      } else if (mode.electricInput) {
        if (mode.electricInput.test(getLine(cm.doc, range$$1.head.line).text.slice(0, range$$1.head.ch)))
          { indented = indentLine(cm, range$$1.head.line, "smart") }
      }
      if (indented) { signalLater(cm, "electricInput", cm, range$$1.head.line) }
    }
  }
  
  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, spellcheck) {
    field.setAttribute("autocorrect", "off")
    field.setAttribute("autocapitalize", "off")
    field.setAttribute("spellcheck", !!spellcheck)
  }
  
  function hiddenTextarea() {
    var te = elt("textarea", null, null, "position: absolute; bottom: -1em; 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
  }
  
  // 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.
  
  var addEditorMethods = function(CodeMirror) {
    var optionHandlers = CodeMirror.optionHandlers
  
    var helpers = CodeMirror.helpers = {}
  
    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$$1, bottom) {
        this.state.keyMaps[bottom ? "push" : "unshift"](getKeyMap(map$$1))
      },
      removeKeyMap: function(map$$1) {
        var maps = this.state.keyMaps
        for (var i = 0; i < maps.length; ++i)
          { if (maps[i] == map$$1 || maps[i].name == map$$1) {
            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.") }
        insertSorted(this.state.overlays,
                     {mode: mode, modeSpec: spec, opaque: options && options.opaque,
                      priority: (options && options.priority) || 0},
                     function (overlay) { return overlay.priority; })
        this.state.modeGen++
        regChange(this)
      }),
      removeOverlay: methodOp(function(spec) {
        var this$1 = this;
  
        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$1.state.modeGen++
            regChange(this$1)
            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 this$1 = this;
  
        var ranges = this.doc.sel.ranges, end = -1
        for (var i = 0; i < ranges.length; i++) {
          var range$$1 = ranges[i]
          if (!range$$1.empty()) {
            var from = range$$1.from(), to = range$$1.to()
            var start = Math.max(end, from.line)
            end = Math.min(this$1.lastLine(), to.line - (to.ch ? 0 : 1)) + 1
            for (var j = start; j < end; ++j)
              { indentLine(this$1, j, how) }
            var newRanges = this$1.doc.sel.ranges
            if (from.ch == 0 && ranges.length == newRanges.length && newRanges[i].from().ch > 0)
              { replaceOneSelection(this$1.doc, i, new Range(from, newRanges[i].to()), sel_dontScroll) }
          } else if (range$$1.head.line > end) {
            indentLine(this$1, range$$1.head.line, how, true)
            end = range$$1.head.line
            if (i == this$1.doc.sel.primIndex) { ensureCursorVisible(this$1) }
          }
        }
      }),
  
      // 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("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 this$1 = this;
  
        var found = []
        if (!helpers.hasOwnProperty(type)) { return found }
        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$1 = 0; i$1 < help._global.length; i$1++) {
          var cur = help._global[i$1]
          if (cur.pred(mode, this$1) && 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$$1 = this.doc.sel.primary()
        if (start == null) { pos = range$$1.head }
        else if (typeof start == "object") { pos = clipPos(this.doc, start) }
        else { pos = start ? range$$1.from() : range$$1.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, lineObj
        if (typeof line == "number") {
          var 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 }
          lineObj = getLine(this.doc, line)
        } else {
          lineObj = 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 this$1 = this;
  
        var doc = this.doc, i = doc.first
        doc.iter(function (line) {
          if (line.gutterMarkers && line.gutterMarkers[gutterID]) {
            line.gutterMarkers[gutterID] = null
            regLineChange(this$1, i, "gutter")
            if (isEmpty(line.gutterMarkers)) { line.gutterMarkers = null }
          }
          ++i
        })
      }),
  
      lineInfo: function(line) {
        var n
        if (typeof line == "number") {
          if (!isLine(this.doc, line)) { return null }
          n = line
          line = getLine(this.doc, line)
          if (!line) { return null }
        } else {
          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].call(null, this) }
      },
  
      triggerElectric: methodOp(function(text) { triggerElectric(this, text) }),
  
      findPosH: function(from, amount, unit, visually) {
        var this$1 = this;
  
        var dir = 1
        if (amount < 0) { dir = -1; amount = -amount }
        var cur = clipPos(this.doc, from)
        for (var i = 0; i < amount; ++i) {
          cur = findPosH(this$1.doc, cur, dir, unit, visually)
          if (cur.hitSide) { break }
        }
        return cur
      },
  
      moveH: methodOp(function(dir, unit) {
        var this$1 = this;
  
        this.extendSelectionsBy(function (range$$1) {
          if (this$1.display.shift || this$1.doc.extend || range$$1.empty())
            { return findPosH(this$1.doc, range$$1.head, dir, unit, this$1.options.rtlMoveVisually) }
          else
            { return dir < 0 ? range$$1.from() : range$$1.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$$1) {
            var other = findPosH(doc, range$$1.head, dir, unit, false)
            return dir < 0 ? {from: other, to: range$$1.head} : {from: range$$1.head, to: other}
          }) }
      }),
  
      findPosV: function(from, amount, unit, goalColumn) {
        var this$1 = this;
  
        var dir = 1, x = goalColumn
        if (amount < 0) { dir = -1; amount = -amount }
        var cur = clipPos(this.doc, from)
        for (var i = 0; i < amount; ++i) {
          var coords = cursorCoords(this$1, cur, "div")
          if (x == null) { x = coords.left }
          else { coords.left = x }
          cur = findPosV(this$1, coords, dir, unit)
          if (cur.hitSide) { break }
        }
        return cur
      },
  
      moveV: methodOp(function(dir, unit) {
        var this$1 = this;
  
        var doc = this.doc, goals = []
        var collapse = !this.display.shift && !doc.extend && doc.sel.somethingSelected()
        doc.extendSelectionsBy(function (range$$1) {
          if (collapse)
            { return dir < 0 ? range$$1.from() : range$$1.to() }
          var headPos = cursorCoords(this$1, range$$1.head, "div")
          if (range$$1.goalColumn != null) { headPos.left = range$$1.goalColumn }
          goals.push(headPos.left)
          var pos = findPosV(this$1, headPos, dir, unit)
          if (unit == "page" && range$$1 == doc.sel.primary())
            { addToScrollPos(this$1, null, charCoords(this$1, 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() },
      isReadOnly: function() { return !!(this.options.readOnly || this.doc.cantEdit) },
  
      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$$1, margin) {
        if (range$$1 == null) {
          range$$1 = {from: this.doc.sel.primary().head, to: null}
          if (margin == null) { margin = this.options.cursorScrollMargin }
        } else if (typeof range$$1 == "number") {
          range$$1 = {from: Pos(range$$1, 0), to: null}
        } else if (range$$1.from == null) {
          range$$1 = {from: range$$1, to: null}
        }
        if (!range$$1.to) { range$$1.to = range$$1.from }
        range$$1.margin = margin || 0
  
        if (range$$1.from.line != null) {
          resolveScrollToPos(this)
          this.curOp.scrollToPos = range$$1
        } else {
          var sPos = calculateScrollPos(this, Math.min(range$$1.from.left, range$$1.to.left),
                                        Math.min(range$$1.from.top, range$$1.to.top) - range$$1.margin,
                                        Math.max(range$$1.from.right, range$$1.to.right),
                                        Math.max(range$$1.from.bottom, range$$1.to.bottom) + range$$1.margin)
          this.scrollTo(sPos.scrollLeft, sPos.scrollTop)
        }
      }),
  
      setSize: methodOp(function(width, height) {
        var this$1 = this;
  
        var interpret = function (val) { return typeof val == "number" || /^\d+$/.test(String(val)) ? val + "px" : val; }
        if (width != null) { this.display.wrapper.style.width = interpret(width) }
        if (height != null) { this.display.wrapper.style.height = interpret(height) }
        if (this.options.lineWrapping) { clearLineMeasurementCache(this) }
        var lineNo$$1 = this.display.viewFrom
        this.doc.iter(lineNo$$1, this.display.viewTo, function (line) {
          if (line.widgets) { for (var i = 0; i < line.widgets.length; i++)
            { if (line.widgets[i].noHScroll) { regLineChange(this$1, lineNo$$1, "widget"); break } } }
          ++lineNo$$1
        })
        this.curOp.forceUpdate = true
        signal(this, "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)
  
    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})
    }
  }
  
  // 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)
    function findNextLine() {
      var l = line + dir
      if (l < doc.first || l >= doc.first + doc.size) { return 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 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), pos, origDir, true)
    if (!cmp(pos, result)) { 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)
      var moveAmount = Math.max(pageSize - .5 * textHeight(cm.display), 3)
      y = (dir > 0 ? pos.bottom : pos.top) + dir * moveAmount
  
    } else if (unit == "line") {
      y = dir > 0 ? pos.bottom + 3 : pos.top - 3
    }
    var target
    for (;;) {
      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
  }
  
  // CONTENTEDITABLE INPUT STYLE
  
  function ContentEditableInput(cm) {
    this.cm = cm
    this.lastAnchorNode = this.lastAnchorOffset = this.lastFocusNode = this.lastFocusOffset = null
    this.polling = new Delayed()
    this.gracePeriod = false
  }
  
  ContentEditableInput.prototype = copyObj({
    init: function(display) {
      var input = this, cm = input.cm
      var div = input.div = display.lineDiv
      disableBrowserMagic(div, cm.options.spellcheck)
  
      on(div, "paste", function (e) {
        if (signalDOMEvent(cm, e) || handlePaste(e, cm)) { return }
        // IE doesn't fire input events, so we schedule a read for the pasted content in this way
        if (ie_version <= 11) { setTimeout(operation(cm, function () {
          if (!input.pollContent()) { regChange(cm) }
        }), 20) }
      })
  
      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) { return 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 () { return input.forceCompositionEnd(); })
  
      on(div, "input", function () {
        if (input.composing) { return }
        if (cm.isReadOnly() || !input.pollContent())
          { runInOp(input.cm, function () { return regChange(cm); }) }
      })
  
      function onCopyCut(e) {
        if (signalDOMEvent(cm, e)) { return }
        if (cm.somethingSelected()) {
          setLastCopied({lineWise: false, text: cm.getSelections()})
          if (e.type == "cut") { cm.replaceSelection("", null, "cut") }
        } else if (!cm.options.lineWiseCopyCut) {
          return
        } else {
          var ranges = copyableRanges(cm)
          setLastCopied({lineWise: true, text: ranges.text})
          if (e.type == "cut") {
            cm.operation(function () {
              cm.setSelections(ranges.ranges, 0, sel_dontScroll)
              cm.replaceSelection("", null, "cut")
            })
          }
        }
        if (e.clipboardData) {
          e.clipboardData.clearData()
          var content = lastCopied.text.join("\n")
          // iOS exposes the clipboard API, but seems to discard content inserted into it
          e.clipboardData.setData("Text", content)
          if (e.clipboardData.getData("Text") == content) {
            e.preventDefault()
            return
          }
        }
        // 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.text.join("\n")
        var hadFocus = document.activeElement
        selectInput(te)
        setTimeout(function () {
          cm.display.lineSpace.removeChild(kludge)
          hadFocus.focus()
          if (hadFocus == div) { input.showPrimarySelection() }
        }, 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, takeFocus) {
      if (!info || !this.cm.display.view.length) { return }
      if (info.focus || takeFocus) { 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$$1 = measure.maps ? measure.maps[measure.maps.length - 1] : measure.map
        end = {node: map$$1[map$$1.length - 1], offset: map$$1[map$$1.length - 2] - map$$1[map$$1.length - 3]}
      }
  
      var rng
      try { 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) {
        if (!gecko && this.cm.state.focused) {
          sel.collapse(start.node, start.offset)
          if (!rng.collapsed) {
            sel.removeAllRanges()
            sel.addRange(rng)
          }
        } else {
          sel.removeAllRanges()
          sel.addRange(rng)
        }
        if (old && sel.anchorNode == null) { sel.addRange(old) }
        else if (gecko) { this.startGracePeriod() }
      }
      this.rememberSelection()
    },
  
    startGracePeriod: function() {
      var this$1 = this;
  
      clearTimeout(this.gracePeriod)
      this.gracePeriod = setTimeout(function () {
        this$1.gracePeriod = false
        if (this$1.selectionChanged())
          { this$1.cm.operation(function () { return this$1.cm.curOp.selectionChanged = true; }) }
      }, 20)
    },
  
    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 () { return 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)
    },
  
    selectionChanged: function() {
      var sel = window.getSelection()
      return sel.anchorNode != this.lastAnchorNode || sel.anchorOffset != this.lastAnchorOffset ||
        sel.focusNode != this.lastFocusNode || sel.focusOffset != this.lastFocusOffset
    },
  
    pollSelection: function() {
      if (!this.composing && !this.gracePeriod && this.selectionChanged()) {
        var sel = window.getSelection(), cm = this.cm
        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, fromLine, fromNode
      if (from.line == display.viewFrom || (fromIndex = findViewIndex(cm, from.line)) == 0) {
        fromLine = lineNo(display.view[0].line)
        fromNode = display.view[0].node
      } else {
        fromLine = lineNo(display.view[fromIndex].line)
        fromNode = display.view[fromIndex - 1].node.nextSibling
      }
      var toIndex = findViewIndex(cm, to.line)
      var toLine, toNode
      if (toIndex == display.view.length - 1) {
        toLine = display.viewTo - 1
        toNode = display.lineDiv.lastChild
      } else {
        toLine = lineNo(display.view[toIndex + 1].line) - 1
        toNode = display.view[toIndex + 1].node.previousSibling
      }
  
      var newText = cm.doc.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 (this.cm.isReadOnly())
        { operation(this.cm, regChange)(this.cm) }
      else if (composing.data && composing.data != composing.startData)
        { operation(this.cm, applyTextInput)(this.cm, composing.data, 0, composing.sel) }
    },
  
    setUneditable: function(node) {
      node.contentEditable = "false"
    },
  
    onKeyPress: function(e) {
      e.preventDefault()
      if (!this.cm.isReadOnly())
        { operation(this.cm, applyTextInput)(this.cm, String.fromCharCode(e.charCode == null ? e.keyCode : e.charCode), 0) }
    },
  
    readOnlyChanged: function(val) {
      this.div.contentEditable = String(val != "nocursor")
    },
  
    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, side)
    result.offset = result.collapse == "right" ? result.end : result.start
    return result
  }
  
  function badPos(pos, bad) { if (bad) { pos.bad = true; } return pos }
  
  function domTextBetween(cm, from, to, fromLine, toLine) {
    var text = "", closing = false, lineSep = cm.doc.lineSeparator()
    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$$1
        if (markerID) {
          var found = cm.findMarks(Pos(fromLine, 0), Pos(toLine + 1, 0), recognizeMarker(+markerID))
          if (found.length && (range$$1 = found[0].find()))
            { text += getBetween(cm.doc, range$$1.from, range$$1.to).join(lineSep) }
          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 += lineSep
          closing = false
        }
        text += val
      }
    }
    for (;;) {
      walk(from)
      if (from == to) { break }
      from = from.nextSibling
    }
    return text
  }
  
  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$$1 = i < 0 ? measure.map : maps[i]
        for (var j = 0; j < map$$1.length; j += 3) {
          var curNode = map$$1[j + 2]
          if (curNode == textNode || curNode == topNode) {
            var line = lineNo(i < 0 ? lineView.line : lineView.rest[i])
            var ch = map$$1[j] + offset
            if (offset < 0 || curNode != textNode) { ch = map$$1[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$1 = offset; before; before = before.previousSibling) {
      found = find(before, before.firstChild, -1)
      if (found)
        { return badPos(Pos(found.line, found.ch + dist$1), bad) }
      else
        { dist$1 += before.textContent.length }
    }
  }
  
  // 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
    this.composing = null
  }
  
  TextareaInput.prototype = copyObj({
    init: function(display) {
      var this$1 = this;
  
      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 && this$1.hasSelection) { this$1.hasSelection = null }
        input.poll()
      })
  
      on(te, "paste", function (e) {
        if (signalDOMEvent(cm, e) || handlePaste(e, cm)) { return }
  
        cm.state.pasteIncoming = true
        input.fastPoll()
      })
  
      function prepareCopyCut(e) {
        if (signalDOMEvent(cm, e)) { return }
        if (cm.somethingSelected()) {
          setLastCopied({lineWise: false, text: cm.getSelections()})
          if (input.inaccurateSelection) {
            input.prevInput = ""
            input.inaccurateSelection = false
            te.value = lastCopied.text.join("\n")
            selectInput(te)
          }
        } else if (!cm.options.lineWiseCopyCut) {
          return
        } else {
          var ranges = copyableRanges(cm)
          setLastCopied({lineWise: true, text: 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) || signalDOMEvent(cm, 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) }
      })
  
      on(te, "compositionstart", function () {
        var start = cm.getCursor("from")
        if (input.composing) { input.composing.range.clear() }
        input.composing = {
          start: start,
          range: cm.markText(start, cm.getCursor("to"), {className: "CodeMirror-composing"})
        }
      })
      on(te, "compositionend", function () {
        if (input.composing) {
          input.poll()
          input.composing.range.clear()
          input.composing = null
        }
      })
    },
  
    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$$1 = doc.sel.primary()
        minimal = hasCopyEvent &&
          (range$$1.to().line - range$$1.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 this$1 = this;
  
      if (this.pollingFast) { return }
      this.polling.set(this.cm.options.pollInterval, function () {
        this$1.poll()
        if (this$1.cm.state.focused) { this$1.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 this$1 = this;
  
      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 (this.contextMenuPending || !cm.state.focused ||
          (hasSelection(input) && !prevInput && !this.composing) ||
          cm.isReadOnly() || cm.options.disableInput || cm.state.keySeq)
        { return 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 (cm.doc.sel == cm.display.selForContextMenu) {
        var first = text.charCodeAt(0)
        if (first == 0x200b && !prevInput) { prevInput = "\u200b" }
        if (first == 0x21da) { this.reset(); return this.cm.execCommand("undo") }
      }
      // 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 }
  
      runInOp(cm, function () {
        applyTextInput(cm, text.slice(same), prevInput.length - same,
                       null, this$1.composing ? "*compose" : null)
  
        // Don't leave long text in the textarea, since it makes further polling slow
        if (text.length > 1000 || text.indexOf("\n") > -1) { input.value = this$1.prevInput = "" }
        else { this$1.prevInput = text }
  
        if (this$1.composing) {
          this$1.composing.range.clear()
          this$1.composing.range = cm.markText(this$1.composing.start, cm.getCursor("to"),
                                             {className: "CodeMirror-composing"})
        }
      })
      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, oldWrapperCSS = input.wrapper.style.cssText
      input.wrapper.style.cssText = "position: absolute"
      var wrapperBox = input.wrapper.getBoundingClientRect()
      te.style.cssText = "position: absolute; width: 30px; height: 30px;\n      top: " + (e.clientY - wrapperBox.top - 5) + "px; left: " + (e.clientX - wrapperBox.left - 5) + "px;\n      z-index: 1000; background: " + (ie ? "rgba(255, 255, 255, .05)" : "transparent") + ";\n      outline: none; border-width: 0; outline: none; overflow: hidden; opacity: .05; filter: alpha(opacity=5);"
      var oldScrollY
      if (webkit) { 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 = "\u200b" + (selected ? te.value : "")
          te.value = "\u21da" // Used to catch context-menu undo
          te.value = extval
          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.cssText = oldWrapperCSS
        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 &&
                te.selectionEnd > 0 && input.prevInput == "\u200b")
              { operation(cm, 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)
      }
    },
  
    readOnlyChanged: function(val) {
      if (!val) { this.reset() }
    },
  
    setUneditable: nothing,
  
    needsContentAttribute: false
  }, TextareaInput.prototype)
  
  function fromTextArea(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()}
  
    var realSubmit
    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$1(function (node) { return textarea.parentNode.insertBefore(node, textarea.nextSibling); },
      options)
    return cm
  }
  
  function addLegacyProps(CodeMirror) {
    CodeMirror.off = off
    CodeMirror.on = on
    CodeMirror.wheelEventPixels = wheelEventPixels
    CodeMirror.Doc = Doc
    CodeMirror.splitLines = splitLinesAuto
    CodeMirror.countColumn = countColumn
    CodeMirror.findColumn = findColumn
    CodeMirror.isWordChar = isWordCharBasic
    CodeMirror.Pass = Pass
    CodeMirror.signal = signal
    CodeMirror.Line = Line
    CodeMirror.changeEnd = changeEnd
    CodeMirror.scrollbarModel = scrollbarModel
    CodeMirror.Pos = Pos
    CodeMirror.cmpPos = cmp
    CodeMirror.modes = modes
    CodeMirror.mimeModes = mimeModes
    CodeMirror.resolveMode = resolveMode
    CodeMirror.getMode = getMode
    CodeMirror.modeExtensions = modeExtensions
    CodeMirror.extendMode = extendMode
    CodeMirror.copyState = copyState
    CodeMirror.startState = startState
    CodeMirror.innerMode = innerMode
    CodeMirror.commands = commands
    CodeMirror.keyMap = keyMap
    CodeMirror.keyName = keyName
    CodeMirror.isModifierKey = isModifierKey
    CodeMirror.lookupKey = lookupKey
    CodeMirror.normalizeKeyMap = normalizeKeyMap
    CodeMirror.StringStream = StringStream
    CodeMirror.SharedTextMarker = SharedTextMarker
    CodeMirror.TextMarker = TextMarker
    CodeMirror.LineWidget = LineWidget
    CodeMirror.e_preventDefault = e_preventDefault
    CodeMirror.e_stopPropagation = e_stopPropagation
    CodeMirror.e_stop = e_stop
    CodeMirror.addClass = addClass
    CodeMirror.contains = contains
    CodeMirror.rmClass = rmClass
    CodeMirror.keyNames = keyNames
  }
  
  // EDITOR CONSTRUCTOR
  
  defineOptions(CodeMirror$1)
  
  addEditorMethods(CodeMirror$1)
  
  // Set up methods on CodeMirror's prototype to redirect to the editor's document.
  var dontDelegate = "iter insert remove copy getEditor constructor".split(" ")
  for (var prop in Doc.prototype) { if (Doc.prototype.hasOwnProperty(prop) && indexOf(dontDelegate, prop) < 0)
    { CodeMirror$1.prototype[prop] = (function(method) {
      return function() {return method.apply(this.doc, arguments)}
    })(Doc.prototype[prop]) } }
  
  eventMixin(Doc)
  
  // INPUT HANDLING
  
  CodeMirror$1.inputStyles = {"textarea": TextareaInput, "contenteditable": ContentEditableInput}
  
  // MODE DEFINITION AND QUERYING
  
  // 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$1.defineMode = function(name/*, mode, …*/) {
    if (!CodeMirror$1.defaults.mode && name != "null") { CodeMirror$1.defaults.mode = name }
    defineMode.apply(this, arguments)
  }
  
  CodeMirror$1.defineMIME = defineMIME
  
  // Minimal default mode.
  CodeMirror$1.defineMode("null", function () { return ({token: function (stream) { return stream.skipToEnd(); }}); })
  CodeMirror$1.defineMIME("text/plain", "null")
  
  // EXTENSIONS
  
  CodeMirror$1.defineExtension = function (name, func) {
    CodeMirror$1.prototype[name] = func
  }
  CodeMirror$1.defineDocExtension = function (name, func) {
    Doc.prototype[name] = func
  }
  
  CodeMirror$1.fromTextArea = fromTextArea
  
  addLegacyProps(CodeMirror$1)
  
  CodeMirror$1.version = "5.20.2"
  
  return CodeMirror$1;
  
  })));
  