text: /* Tokenizer for JavaScript code */
  
  var tokenizeJavaScript = (function() {
    // Advance the stream until the given character (not preceded by a
    // backslash) is encountered, or the end of the line is reached.
    function nextUntilUnescaped(source, end) {
      var escaped = false;
      var next;
      while (!source.endOfLine()) {
        var next = source.next();
        if (next == end && !escaped)
          return false;
        escaped = !escaped && next == "\\";
      }
      return escaped;
    }
  
    // A map of JavaScript's keywords. The a/b/c keyword distinction is
    // very rough, but it gives the parser enough information to parse
    // correct code correctly (we don't care that much how we parse
    // incorrect code). The style information included in these objects
    // is used by the highlighter to pick the correct CSS style for a
    // token.
    var keywords = function(){
      function result(type, style){
        return {type: type, style: "js-" + style};
      }
      // keywords that take a parenthised expression, and then a
      // statement (if)
      var keywordA = result("keyword a", "keyword");
      // keywords that take just a statement (else)
      var keywordB = result("keyword b", "keyword");
      // keywords that optionally take an expression, and form a
      // statement (return)
      var keywordC = result("keyword c", "keyword");
      var operator = result("operator", "keyword");
      var atom = result("atom", "atom");
      return {
        "if": keywordA, "while": keywordA, "with": keywordA,
        "else": keywordB, "do": keywordB, "try": keywordB, "finally": keywordB,
        "return": keywordC, "break": keywordC, "continue": keywordC, "new": keywordC, "delete": keywordC, "throw": keywordC,
        "in": operator, "typeof": operator, "instanceof": operator,
        "var": result("var", "keyword"), "function": result("function", "keyword"), "catch": result("catch", "keyword"),
        "for": result("for", "keyword"), "switch": result("switch", "keyword"),
        "case": result("case", "keyword"), "default": result("default", "keyword"),
        "true": atom, "false": atom, "null": atom, "undefined": atom, "NaN": atom, "Infinity": atom
      };
    }();
  
    // Some helper regexps
    var isOperatorChar = /[+\-*&%=<>!?|]/;
    var isHexDigit = /[0-9A-Fa-f]/;
    var isWordChar = /[\w\$_]/;
  
    // Wrapper around jsToken that helps maintain parser state (whether
    // we are inside of a multi-line comment and whether the next token
    // could be a regular expression).
    function jsTokenState(inside, regexp) {
      return function(source, setState) {
        var newInside = inside;
        var type = jsToken(inside, regexp, source, function(c) {newInside = c;});
        var newRegexp = type.type == "operator" || type.type == "keyword c" || type.type.match(/^[\[{}\(,;:]$/);
        if (newRegexp != regexp || newInside != inside)
          setState(jsTokenState(newInside, newRegexp));
        return type;
      };
    }
  
    // The token reader, inteded to be used by the tokenizer from
    // tokenize.js (through jsTokenState). Advances the source stream
    // over a token, and returns an object containing the type and style
    // of that token.
    function jsToken(inside, regexp, source, setInside) {
      function readHexNumber(){
        source.next(); // skip the 'x'
        source.nextWhileMatches(isHexDigit);
        return {type: "number", style: "js-atom"};
      }
  
      function readNumber() {
        source.nextWhileMatches(/[0-9]/);
        if (source.equals(".")){
          source.next();
          source.nextWhileMatches(/[0-9]/);
        }
        if (source.equals("e") || source.equals("E")){
          source.next();
          if (source.equals("-"))
            source.next();
          source.nextWhileMatches(/[0-9]/);
        }
        return {type: "number", style: "js-atom"};
      }
      // Read a word, look it up in keywords. If not found, it is a
      // variable, otherwise it is a keyword of the type found.
      function readWord() {
        source.nextWhileMatches(isWordChar);
        var word = source.get();
        var known = keywords.hasOwnProperty(word) && keywords.propertyIsEnumerable(word) && keywords[word];
        return known ? {type: known.type, style: known.style, content: word} :
        {type: "variable", style: "js-variable", content: word};
      }
      function readRegexp() {
        nextUntilUnescaped(source, "/");
        source.nextWhileMatches(/[gi]/);
        return {type: "regexp", style: "js-string"};
      }
      // Mutli-line comments are tricky. We want to return the newlines
      // embedded in them as regular newline tokens, and then continue
      // returning a comment token for every line of the comment. So
      // some state has to be saved (inside) to indicate whether we are
      // inside a /* */ sequence.
      function readMultilineComment(start){
        var newInside = "/*";
        var maybeEnd = (start == "*");
        while (true) {
          if (source.endOfLine())
            break;
          var next = source.next();
          if (next == "/" && maybeEnd){
            newInside = null;
            break;
          }
          maybeEnd = (next == "*");
        }
        setInside(newInside);
        return {type: "comment", style: "js-comment"};
      }
      function readOperator() {
        source.nextWhileMatches(isOperatorChar);
        return {type: "operator", style: "js-operator"};
      }
      function readString(quote) {
        var endBackSlash = nextUntilUnescaped(source, quote);
        setInside(endBackSlash ? quote : null);
        return {type: "string", style: "js-string"};
      }
  
      // Fetch the next token. Dispatches on first character in the
      // stream, or first two characters when the first is a slash.
      if (inside == "\"" || inside == "'")
        return readString(inside);
      var ch = source.next();
      if (inside == "/*")
        return readMultilineComment(ch);
      else if (ch == "\"" || ch == "'")
        return readString(ch);
      // with punctuation, the type of the token is the symbol itself
      else if (/[\[\]{}\(\),;\:\.]/.test(ch))
        return {type: ch, style: "js-punctuation"};
      else if (ch == "0" && (source.equals("x") || source.equals("X")))
        return readHexNumber();
      else if (/[0-9]/.test(ch))
        return readNumber();
      else if (ch == "/"){
        if (source.equals("*"))
        { source.next(); return readMultilineComment(ch); }
        else if (source.equals("/"))
        { nextUntilUnescaped(source, null); return {type: "comment", style: "js-comment"};}
        else if (regexp)
          return readRegexp();
        else
          return readOperator();
      }
      else if (isOperatorChar.test(ch))
        return readOperator();
      else
        return readWord();
    }
  
    // The external interface to the tokenizer.
    return function(source, startState) {
      return tokenizer(source, startState || jsTokenState(false, true));
    };
  })();
  