// Copyright (C) 2006 Google Inc. // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. /** * @fileoverview * some functions for browser-side pretty printing of code contained in html. *

* * For a fairly comprehensive set of languages see the * README * file that came with this source. At a minimum, the lexer should work on a * number of languages including C and friends, Java, Python, Bash, SQL, HTML, * XML, CSS, Javascript, and Makefiles. It works passably on Ruby, PHP and Awk * and a subset of Perl, but, because of commenting conventions, doesn't work on * Smalltalk, Lisp-like, or CAML-like languages without an explicit lang class. *

* Usage:

    *
  1. include this source file in an html page via * {@code } *
  2. define style rules. See the example page for examples. *
  3. mark the {@code
    } and {@code } tags in your source with
     *    {@code class=prettyprint.}
     *    You can also use the (html deprecated) {@code } tag, but the pretty
     *    printer needs to do more substantial DOM manipulations to support that, so
     *    some css styles may not be preserved.
     * </ol>
     * That's it.  I wanted to keep the API as simple as possible, so there's no
     * need to specify which language the code is in, but if you wish, you can add
     * another class to the {@code <pre>} or {@code <code>} element to specify the
     * language, as in {@code <pre class="prettyprint lang-java">}.  Any class that
     * starts with "lang-" followed by a file extension, specifies the file type.
     * See the "lang-*.js" files in this directory for code that implements
     * per-language file handlers.
     * <p>
     * Change log:<br>
     * cbeust, 2006/08/22
     * <blockquote>
     *   Java annotations (start with "@") are now captured as literals ("lit")
     * </blockquote>
     * @requires console
     */
    
    // JSLint declarations
    /*global console, document, navigator, setTimeout, window */
    
    /**
     * Split {@code prettyPrint} into multiple timeouts so as not to interfere with
     * UI events.
     * If set to {@code false}, {@code prettyPrint()} is synchronous.
     */
    window['PR_SHOULD_USE_CONTINUATION'] = true;
    
    /** the number of characters between tab columns */
    window['PR_TAB_WIDTH'] = 8;
    
    /** Walks the DOM returning a properly escaped version of innerHTML.
      * @param {Node} node
      * @param {Array.<string>} out output buffer that receives chunks of HTML.
      */
    window['PR_normalizedHtml']
    
    /** Contains functions for creating and registering new language handlers.
      * @type {Object}
      */
      = window['PR']
    
    /** Pretty print a chunk of code.
      *
      * @param {string} sourceCodeHtml code as html
      * @return {string} code as html, but prettier
      */
      = window['prettyPrintOne']
    /** Find all the {@code <pre>} and {@code <code>} tags in the DOM with
      * {@code class=prettyprint} and prettify them.
      * @param {Function?} opt_whenDone if specified, called when the last entry
      *     has been finished.
      */
      = window['prettyPrint'] = void 0;
    
    /** browser detection. @extern @returns false if not IE, otherwise the major version. */
    window['_pr_isIE6'] = function () {
      var ieVersion = navigator && navigator.userAgent &&
          navigator.userAgent.match(/\bMSIE ([678])\./);
      ieVersion = ieVersion ? +ieVersion[1] : false;
      window['_pr_isIE6'] = function () { return ieVersion; };
      return ieVersion;
    };
    
    
    (function () {
      // Keyword lists for various languages.
      var FLOW_CONTROL_KEYWORDS =
          "break continue do else for if return while ";
      var C_KEYWORDS = FLOW_CONTROL_KEYWORDS + "auto case char const default " +
          "double enum extern float goto int long register short signed sizeof " +
          "static struct switch typedef union unsigned void volatile ";
      var COMMON_KEYWORDS = C_KEYWORDS + "catch class delete false import " +
          "new operator private protected public this throw true try typeof ";
      var CPP_KEYWORDS = COMMON_KEYWORDS + "alignof align_union asm axiom bool " +
          "concept concept_map const_cast constexpr decltype " +
          "dynamic_cast explicit export friend inline late_check " +
          "mutable namespace nullptr reinterpret_cast static_assert static_cast " +
          "template typeid typename using virtual wchar_t where ";
      var JAVA_KEYWORDS = COMMON_KEYWORDS +
          "abstract boolean byte extends final finally implements import " +
          "instanceof null native package strictfp super synchronized throws " +
          "transient ";
      var CSHARP_KEYWORDS = JAVA_KEYWORDS +
          "as base by checked decimal delegate descending event " +
          "fixed foreach from group implicit in interface internal into is lock " +
          "object out override orderby params partial readonly ref sbyte sealed " +
          "stackalloc string select uint ulong unchecked unsafe ushort var ";
      var JSCRIPT_KEYWORDS = COMMON_KEYWORDS +
          "debugger eval export function get null set undefined var with " +
          "Infinity NaN ";
      var PERL_KEYWORDS = "caller delete die do dump elsif eval exit foreach for " +
          "goto if import last local my next no our print package redo require " +
          "sub undef unless until use wantarray while BEGIN END ";
      var PYTHON_KEYWORDS = FLOW_CONTROL_KEYWORDS + "and as assert class def del " +
          "elif except exec finally from global import in is lambda " +
          "nonlocal not or pass print raise try with yield " +
          "False True None ";
      var RUBY_KEYWORDS = FLOW_CONTROL_KEYWORDS + "alias and begin case class def" +
          " defined elsif end ensure false in module next nil not or redo rescue " +
          "retry self super then true undef unless until when yield BEGIN END ";
      var SH_KEYWORDS = FLOW_CONTROL_KEYWORDS + "case done elif esac eval fi " +
          "function in local set then until ";
      var ALL_KEYWORDS = (
          CPP_KEYWORDS + CSHARP_KEYWORDS + JSCRIPT_KEYWORDS + PERL_KEYWORDS +
          PYTHON_KEYWORDS + RUBY_KEYWORDS + SH_KEYWORDS);
    
      // token style names.  correspond to css classes
      /** token style for a string literal */
      var PR_STRING = 'str';
      /** token style for a keyword */
      var PR_KEYWORD = 'kwd';
      /** token style for a comment */
      var PR_COMMENT = 'com';
      /** token style for a type */
      var PR_TYPE = 'typ';
      /** token style for a literal value.  e.g. 1, null, true. */
      var PR_LITERAL = 'lit';
      /** token style for a punctuation string. */
      var PR_PUNCTUATION = 'pun';
      /** token style for a punctuation string. */
      var PR_PLAIN = 'pln';
    
      /** token style for an sgml tag. */
      var PR_TAG = 'tag';
      /** token style for a markup declaration such as a DOCTYPE. */
      var PR_DECLARATION = 'dec';
      /** token style for embedded source. */
      var PR_SOURCE = 'src';
      /** token style for an sgml attribute name. */
      var PR_ATTRIB_NAME = 'atn';
      /** token style for an sgml attribute value. */
      var PR_ATTRIB_VALUE = 'atv';
    
      /**
       * A class that indicates a section of markup that is not code, e.g. to allow
       * embedding of line numbers within code listings.
       */
      var PR_NOCODE = 'nocode';
    
      /** A set of tokens that can precede a regular expression literal in
        * javascript.
        * http://www.mozilla.org/js/language/js20/rationale/syntax.html has the full
        * list, but I've removed ones that might be problematic when seen in
        * languages that don't support regular expression literals.
        *
        * <p>Specifically, I've removed any keywords that can't precede a regexp
        * literal in a syntactically legal javascript program, and I've removed the
        * "in" keyword since it's not a keyword in many languages, and might be used
        * as a count of inches.
        *
        * <p>The link a above does not accurately describe EcmaScript rules since
        * it fails to distinguish between (a=++/b/i) and (a++/b/i) but it works
        * very well in practice.
        *
        * @private
        */
      var REGEXP_PRECEDER_PATTERN = function () {
          var preceders = [
              "!", "!=", "!==", "#", "%", "%=", "&", "&&", "&&=",
              "&=", "(", "*", "*=", /* "+", */ "+=", ",", /* "-", */ "-=",
              "->", /*".", "..", "...", handled below */ "/", "/=", ":", "::", ";",
              "<", "<<", "<<=", "<=", "=", "==", "===", ">",
              ">=", ">>", ">>=", ">>>", ">>>=", "?", "@", "[",
              "^", "^=", "^^", "^^=", "{", "|", "|=", "||",
              "||=", "~" /* handles =~ and !~ */,
              "break", "case", "continue", "delete",
              "do", "else", "finally", "instanceof",
              "return", "throw", "try", "typeof"
              ];
          var pattern = '(?:^^|[+-]';
          for (var i = 0; i < preceders.length; ++i) {
            pattern += '|' + preceders[i].replace(/([^=<>:&a-z])/g, '\\$1');
          }
          pattern += ')\\s*';  // matches at end, and matches empty string
          return pattern;
          // CAVEAT: this does not properly handle the case where a regular
          // expression immediately follows another since a regular expression may
          // have flags for case-sensitivity and the like.  Having regexp tokens
          // adjacent is not valid in any language I'm aware of, so I'm punting.
          // TODO: maybe style special characters inside a regexp as punctuation.
        }();
    
      // Define regexps here so that the interpreter doesn't have to create an
      // object each time the function containing them is called.
      // The language spec requires a new object created even if you don't access
      // the $1 members.
      var pr_amp = /&/g;
      var pr_lt = /</g;
      var pr_gt = />/g;
      var pr_quot = /\"/g;
      /** like textToHtml but escapes double quotes to be attribute safe. */
      function attribToHtml(str) {
        return str.replace(pr_amp, '&amp;')
            .replace(pr_lt, '&lt;')
            .replace(pr_gt, '&gt;')
            .replace(pr_quot, '&quot;');
      }
    
      /** escapest html special characters to html. */
      function textToHtml(str) {
        return str.replace(pr_amp, '&amp;')
            .replace(pr_lt, '&lt;')
            .replace(pr_gt, '&gt;');
      }
    
    
      var pr_ltEnt = /&lt;/g;
      var pr_gtEnt = /&gt;/g;
      var pr_aposEnt = /&apos;/g;
      var pr_quotEnt = /&quot;/g;
      var pr_ampEnt = /&amp;/g;
      var pr_nbspEnt = /&nbsp;/g;
      /** unescapes html to plain text. */
      function htmlToText(html) {
        var pos = html.indexOf('&');
        if (pos < 0) { return html; }
        // Handle numeric entities specially.  We can't use functional substitution
        // since that doesn't work in older versions of Safari.
        // These should be rare since most browsers convert them to normal chars.
        for (--pos; (pos = html.indexOf('&#', pos + 1)) >= 0;) {
          var end = html.indexOf(';', pos);
          if (end >= 0) {
            var num = html.substring(pos + 3, end);
            var radix = 10;
            if (num && num.charAt(0) === 'x') {
              num = num.substring(1);
              radix = 16;
            }
            var codePoint = parseInt(num, radix);
            if (!isNaN(codePoint)) {
              html = (html.substring(0, pos) + String.fromCharCode(codePoint) +
                      html.substring(end + 1));
            }
          }
        }
    
        return html.replace(pr_ltEnt, '<')
            .replace(pr_gtEnt, '>')
            .replace(pr_aposEnt, "'")
            .replace(pr_quotEnt, '"')
            .replace(pr_nbspEnt, ' ')
            .replace(pr_ampEnt, '&');
      }
    
      /** is the given node's innerHTML normally unescaped? */
      function isRawContent(node) {
        return 'XMP' === node.tagName;
      }
    
      var newlineRe = /[\r\n]/g;
      /**
       * Are newlines and adjacent spaces significant in the given node's innerHTML?
       */
      function isPreformatted(node, content) {
        // PRE means preformatted, and is a very common case, so don't create
        // unnecessary computed style objects.
        if ('PRE' === node.tagName) { return true; }
        if (!newlineRe.test(content)) { return true; }  // Don't care
        var whitespace = '';
        // For disconnected nodes, IE has no currentStyle.
        if (node.currentStyle) {
          whitespace = node.currentStyle.whiteSpace;
        } else if (window.getComputedStyle) {
          // Firefox makes a best guess if node is disconnected whereas Safari
          // returns the empty string.
          whitespace = window.getComputedStyle(node, null).whiteSpace;
        }
        return !whitespace || whitespace === 'pre';
      }
    
      function normalizedHtml(node, out, opt_sortAttrs) {
        switch (node.nodeType) {
          case 1:  // an element
            var name = node.tagName.toLowerCase();
    
            out.push('<', name);
            var attrs = node.attributes;
            var n = attrs.length;
            if (n) {
              if (opt_sortAttrs) {
                var sortedAttrs = [];
                for (var i = n; --i >= 0;) { sortedAttrs[i] = attrs[i]; }
                sortedAttrs.sort(function (a, b) {
                    return (a.name < b.name) ? -1 : a.name === b.name ? 0 : 1;
                  });
                attrs = sortedAttrs;
              }
              for (var i = 0; i < n; ++i) {
                var attr = attrs[i];
                if (!attr.specified) { continue; }
                out.push(' ', attr.name.toLowerCase(),
                         '="', attribToHtml(attr.value), '"');
              }
            }
            out.push('>');
            for (var child = node.firstChild; child; child = child.nextSibling) {
              normalizedHtml(child, out, opt_sortAttrs);
            }
            if (node.firstChild || !/^(?:br|link|img)$/.test(name)) {
              out.push('<\/', name, '>');
            }
            break;
          case 3: case 4: // text
            out.push(textToHtml(node.nodeValue));
            break;
        }
      }
    
      /**
       * Given a group of {@link RegExp}s, returns a {@code RegExp} that globally
       * matches the union o the sets o strings matched d by the input RegExp.
       * Since it matches globally, if the input strings have a start-of-input
       * anchor (/^.../), it is ignored for the purposes of unioning.
       * @param {Array.<RegExp>} regexs non multiline, non-global regexs.
       * @return {RegExp} a global regex.
       */
      function combinePrefixPatterns(regexs) {
        var capturedGroupIndex = 0;
    
        var needToFoldCase = false;
        var ignoreCase = false;
        for (var i = 0, n = regexs.length; i < n; ++i) {
          var regex = regexs[i];
          if (regex.ignoreCase) {
            ignoreCase = true;
          } else if (/[a-z]/i.test(regex.source.replace(
                         /\\u[0-9a-f]{4}|\\x[0-9a-f]{2}|\\[^ux]/gi, ''))) {
            needToFoldCase = true;
            ignoreCase = false;
            break;
          }
        }
    
        function decodeEscape(charsetPart) {
          if (charsetPart.charAt(0) !== '\\') { return charsetPart.charCodeAt(0); }
          switch (charsetPart.charAt(1)) {
            case 'b': return 8;
            case 't': return 9;
            case 'n': return 0xa;
            case 'v': return 0xb;
            case 'f': return 0xc;
            case 'r': return 0xd;
            case 'u': case 'x':
              return parseInt(charsetPart.substring(2), 16)
                  || charsetPart.charCodeAt(1);
            case '0': case '1': case '2': case '3': case '4':
            case '5': case '6': case '7':
              return parseInt(charsetPart.substring(1), 8);
            default: return charsetPart.charCodeAt(1);
          }
        }
    
        function encodeEscape(charCode) {
          if (charCode < 0x20) {
            return (charCode < 0x10 ? '\\x0' : '\\x') + charCode.toString(16);
          }
          var ch = String.fromCharCode(charCode);
          if (ch === '\\' || ch === '-' || ch === '[' || ch === ']') {
            ch = '\\' + ch;
          }
          return ch;
        }
    
        function caseFoldCharset(charSet) {
          var charsetParts = charSet.substring(1, charSet.length - 1).match(
              new RegExp(
                  '\\\\u[0-9A-Fa-f]{4}'
                  + '|\\\\x[0-9A-Fa-f]{2}'
                  + '|\\\\[0-3][0-7]{0,2}'
                  + '|\\\\[0-7]{1,2}'
                  + '|\\\\[\\s\\S]'
                  + '|-'
                  + '|[^-\\\\]',
                  'g'));
          var groups = [];
          var ranges = [];
          var inverse = charsetParts[0] === '^';
          for (var i = inverse ? 1 : 0, n = charsetParts.length; i < n; ++i) {
            var p = charsetParts[i];
            switch (p) {
              case '\\B': case '\\b':
              case '\\D': case '\\d':
              case '\\S': case '\\s':
              case '\\W': case '\\w':
                groups.push(p);
                continue;
            }
            var start = decodeEscape(p);
            var end;
            if (i + 2 < n && '-' === charsetParts[i + 1]) {
              end = decodeEscape(charsetParts[i + 2]);
              i += 2;
            } else {
              end = start;
            }
            ranges.push([start, end]);
            // If the range might intersect letters, then expand it.
            if (!(end < 65 || start > 122)) {
              if (!(end < 65 || start > 90)) {
                ranges.push([Math.max(65, start) | 32, Math.min(end, 90) | 32]);
              }
              if (!(end < 97 || start > 122)) {
                ranges.push([Math.max(97, start) & ~32, Math.min(end, 122) & ~32]);
              }
            }
          }
    
          // [[1, 10], [3, 4], [8, 12], [14, 14], [16, 16], [17, 17]]
          // -> [[1, 12], [14, 14], [16, 17]]
          ranges.sort(function (a, b) { return (a[0] - b[0]) || (b[1]  - a[1]); });
          var consolidatedRanges = [];
          var lastRange = [NaN, NaN];
          for (var i = 0; i < ranges.length; ++i) {
            var range = ranges[i];
            if (range[0] <= lastRange[1] + 1) {
              lastRange[1] = Math.max(lastRange[1], range[1]);
            } else {
              consolidatedRanges.push(lastRange = range);
            }
          }
    
          var out = ['['];
          if (inverse) { out.push('^'); }
          out.push.apply(out, groups);
          for (var i = 0; i < consolidatedRanges.length; ++i) {
            var range = consolidatedRanges[i];
            out.push(encodeEscape(range[0]));
            if (range[1] > range[0]) {
              if (range[1] + 1 > range[0]) { out.push('-'); }
              out.push(encodeEscape(range[1]));
            }
          }
          out.push(']');
          return out.join('');
        }
    
        function allowAnywhereFoldCaseAndRenumberGroups(regex) {
          // Split into character sets, escape sequences, punctuation strings
          // like ('(', '(?:', ')', '^'), and runs of characters that do not
          // include any of the above.
          var parts = regex.source.match(
              new RegExp(
                  '(?:'
                  + '\\[(?:[^\\x5C\\x5D]|\\\\[\\s\\S])*\\]'  // a character set
                  + '|\\\\u[A-Fa-f0-9]{4}'  // a unicode escape
                  + '|\\\\x[A-Fa-f0-9]{2}'  // a hex escape
                  + '|\\\\[0-9]+'  // a back-reference or octal escape
                  + '|\\\\[^ux0-9]'  // other escape sequence
                  + '|\\(\\?[:!=]'  // start of a non-capturing group
                  + '|[\\(\\)\\^]'  // start/emd of a group, or line start
                  + '|[^\\x5B\\x5C\\(\\)\\^]+'  // run of other characters
                  + ')',
                  'g'));
          var n = parts.length;
    
          // Maps captured group numbers to the number they will occupy in
          // the output or to -1 if that has not been determined, or to
          // undefined if they need not be capturing in the output.
          var capturedGroups = [];
    
          // Walk over and identify back references to build the capturedGroups
          // mapping.
          for (var i = 0, groupIndex = 0; i < n; ++i) {
            var p = parts[i];
            if (p === '(') {
              // groups are 1-indexed, so max group index is count of '('
              ++groupIndex;
            } else if ('\\' === p.charAt(0)) {
              var decimalValue = +p.substring(1);
              if (decimalValue && decimalValue <= groupIndex) {
                capturedGroups[decimalValue] = -1;
              }
            }
          }
    
          // Renumber groups and reduce capturing groups to non-capturing groups
          // where possible.
          for (var i = 1; i < capturedGroups.length; ++i) {
            if (-1 === capturedGroups[i]) {
              capturedGroups[i] = ++capturedGroupIndex;
            }
          }
          for (var i = 0, groupIndex = 0; i < n; ++i) {
            var p = parts[i];
            if (p === '(') {
              ++groupIndex;
              if (capturedGroups[groupIndex] === undefined) {
                parts[i] = '(?:';
              }
            } else if ('\\' === p.charAt(0)) {
              var decimalValue = +p.substring(1);
              if (decimalValue && decimalValue <= groupIndex) {
                parts[i] = '\\' + capturedGroups[groupIndex];
              }
            }
          }
    
          // Remove any prefix anchors so that the output will match anywhere.
          // ^^ really does mean an anchored match though.
          for (var i = 0, groupIndex = 0; i < n; ++i) {
            if ('^' === parts[i] && '^' !== parts[i + 1]) { parts[i] = ''; }
          }
    
          // Expand letters to groupts to handle mixing of case-sensitive and
          // case-insensitive patterns if necessary.
          if (regex.ignoreCase && needToFoldCase) {
            for (var i = 0; i < n; ++i) {
              var p = parts[i];
              var ch0 = p.charAt(0);
              if (p.length >= 2 && ch0 === '[') {
                parts[i] = caseFoldCharset(p);
              } else if (ch0 !== '\\') {
                // TODO: handle letters in numeric escapes.
                parts[i] = p.replace(
                    /[a-zA-Z]/g,
                    function (ch) {
                      var cc = ch.charCodeAt(0);
                      return '[' + String.fromCharCode(cc & ~32, cc | 32) + ']';
                    });
              }
            }
          }
    
          return parts.join('');
        }
    
        var rewritten = [];
        for (var i = 0, n = regexs.length; i < n; ++i) {
          var regex = regexs[i];
          if (regex.global || regex.multiline) { throw new Error('' + regex); }
          rewritten.push(
              '(?:' + allowAnywhereFoldCaseAndRenumberGroups(regex) + ')');
        }
    
        return new RegExp(rewritten.join('|'), ignoreCase ? 'gi' : 'g');
      }
    
      var PR_innerHtmlWorks = null;
      function getInnerHtml(node) {
        // inner html is hopelessly broken in Safari 2.0.4 when the content is
        // an html description of well formed XML and the containing tag is a PRE
        // tag, so we detect that case and emulate innerHTML.
        if (null === PR_innerHtmlWorks) {
          var testNode = document.createElement('PRE');
          testNode.appendChild(
              document.createTextNode('<!DOCTYPE foo PUBLIC "foo bar">\n<foo />'));
          PR_innerHtmlWorks = !/</.test(testNode.innerHTML);
        }
    
        if (PR_innerHtmlWorks) {
          var content = node.innerHTML;
          // XMP tags contain unescaped entities so require special handling.
          if (isRawContent(node)) {
            content = textToHtml(content);
          } else if (!isPreformatted(node, content)) {
            content = content.replace(/(<br\s*\/?>)[\r\n]+/g, '$1')
                .replace(/(?:[\r\n]+[ \t]*)+/g, ' ');
          }
          return content;
        }
    
        var out = [];
        for (var child = node.firstChild; child; child = child.nextSibling) {
          normalizedHtml(child, out);
        }
        return out.join('');
      }
    
      /** returns a function that expand tabs to spaces.  This function can be fed
        * successive chunks of text, and will maintain its own internal state to
        * keep track of how tabs are expanded.
        * @return {function (string) : string} a function that takes
        *   plain text and return the text with tabs expanded.
        * @private
        */
      function makeTabExpander(tabWidth) {
        var SPACES = '                ';
        var charInLine = 0;
    
        return function (plainText) {
          // walk over each character looking for tabs and newlines.
          // On tabs, expand them.  On newlines, reset charInLine.
          // Otherwise increment charInLine
          var out = null;
          var pos = 0;
          for (var i = 0, n = plainText.length; i < n; ++i) {
            var ch = plainText.charAt(i);
    
            switch (ch) {
              case '\t':
                if (!out) { out = []; }
                out.push(plainText.substring(pos, i));
                // calculate how much space we need in front of this part
                // nSpaces is the amount of padding -- the number of spaces needed
                // to move us to the next column, where columns occur at factors of
                // tabWidth.
                var nSpaces = tabWidth - (charInLine % tabWidth);
                charInLine += nSpaces;
                for (; nSpaces >= 0; nSpaces -= SPACES.length) {
                  out.push(SPACES.substring(0, nSpaces));
                }
                pos = i + 1;
                break;
              case '\n':
                charInLine = 0;
                break;
              default:
                ++charInLine;
            }
          }
          if (!out) { return plainText; }
          out.push(plainText.substring(pos));
          return out.join('');
        };
      }
    
      var pr_chunkPattern = new RegExp(
          '[^<]+'  // A run of characters other than '<'
          + '|<\!--[\\s\\S]*?--\>'  // an HTML comment
          + '|<!\\[CDATA\\[[\\s\\S]*?\\]\\]>'  // a CDATA section
          // a probable tag that should not be highlighted
          + '|<\/?[a-zA-Z](?:[^>\"\']|\'[^\']*\'|\"[^\"]*\")*>'
          + '|<',  // A '<' that does not begin a larger chunk
          'g');
      var pr_commentPrefix = /^<\!--/;
      var pr_cdataPrefix = /^<!\[CDATA\[/;
      var pr_brPrefix = /^<br\b/i;
      var pr_tagNameRe = /^<(\/?)([a-zA-Z][a-zA-Z0-9]*)/;
    
      /** split markup into chunks of html tags (style null) and
        * plain text (style {@link #PR_PLAIN}), converting tags which are
        * significant for tokenization (<br>) into their textual equivalent.
        *
        * @param {string} s html where whitespace is considered significant.
        * @return {Object} source code and extracted tags.
        * @private
        */
      function extractTags(s) {
        // since the pattern has the 'g' modifier and defines no capturing groups,
        // this will return a list of all chunks which we then classify and wrap as
        // PR_Tokens
        var matches = s.match(pr_chunkPattern);
        var sourceBuf = [];
        var sourceBufLen = 0;
        var extractedTags = [];
        if (matches) {
          for (var i = 0, n = matches.length; i < n; ++i) {
            var match = matches[i];
            if (match.length > 1 && match.charAt(0) === '<') {
              if (pr_commentPrefix.test(match)) { continue; }
              if (pr_cdataPrefix.test(match)) {
                // strip CDATA prefix and suffix.  Don't unescape since it's CDATA
                sourceBuf.push(match.substring(9, match.length - 3));
                sourceBufLen += match.length - 12;
              } else if (pr_brPrefix.test(match)) {
                // <br> tags are lexically significant so convert them to text.
                // This is undone later.
                sourceBuf.push('\n');
                ++sourceBufLen;
              } else {
                if (match.indexOf(PR_NOCODE) >= 0 && isNoCodeTag(match)) {
                  // A <span class="nocode"> will start a section that should be
                  // ignored.  Continue walking the list until we see a matching end
                  // tag.
                  var name = match.match(pr_tagNameRe)[2];
                  var depth = 1;
                  var j;
                  end_tag_loop:
                  for (j = i + 1; j < n; ++j) {
                    var name2 = matches[j].match(pr_tagNameRe);
                    if (name2 && name2[2] === name) {
                      if (name2[1] === '/') {
                        if (--depth === 0) { break end_tag_loop; }
                      } else {
                        ++depth;
                      }
                    }
                  }
                  if (j < n) {
                    extractedTags.push(
                        sourceBufLen, matches.slice(i, j + 1).join(''));
                    i = j;
                  } else {  // Ignore unclosed sections.
                    extractedTags.push(sourceBufLen, match);
                  }
                } else {
                  extractedTags.push(sourceBufLen, match);
                }
              }
            } else {
              var literalText = htmlToText(match);
              sourceBuf.push(literalText);
              sourceBufLen += literalText.length;
            }
          }
        }
        return { source: sourceBuf.join(''), tags: extractedTags };
      }
    
      /** True if the given tag contains a class attribute with the nocode class. */
      function isNoCodeTag(tag) {
        return !!tag
            // First canonicalize the representation of attributes
            .replace(/\s(\w+)\s*=\s*(?:\"([^\"]*)\"|'([^\']*)'|(\S+))/g,
                     ' $1="$2$3$4"')
            // Then look for the attribute we want.
            .match(/[cC][lL][aA][sS][sS]=\"[^\"]*\bnocode\b/);
      }
    
      /**
       * Apply the given language handler to sourceCode and add the resulting
       * decorations to out.
       * @param {number} basePos the index of sourceCode within the chunk of source
       *    whose decorations are already present on out.
       */
      function appendDecorations(basePos, sourceCode, langHandler, out) {
        if (!sourceCode) { return; }
        var job = {
          source: sourceCode,
          basePos: basePos
        };
        langHandler(job);
        out.push.apply(out, job.decorations);
      }
    
      /** Given triples of [style, pattern, context] returns a lexing function,
        * The lexing function interprets the patterns to find token boundaries and
        * returns a decoration list of the form
        * [index_0, style_0, index_1, style_1, ..., index_n, style_n]
        * where index_n is an index into the sourceCode, and style_n is a style
        * constant like PR_PLAIN.  index_n-1 <= index_n, and style_n-1 applies to
        * all characters in sourceCode[index_n-1:index_n].
        *
        * The stylePatterns is a list whose elements have the form
        * [style : string, pattern : RegExp, DEPRECATED, shortcut : string].
        *
        * Style is a style constant like PR_PLAIN, or can be a string of the
        * form 'lang-FOO', where FOO is a language extension describing the
        * language of the portion of the token in $1 after pattern executes.
        * E.g., if style is 'lang-lisp', and group 1 contains the text
        * '(hello (world))', then that portion of the token will be passed to the
        * registered lisp handler for formatting.
        * The text before and after group 1 will be restyled using this decorator
        * so decorators should take care that this doesn't result in infinite
        * recursion.  For example, the HTML lexer rule for SCRIPT elements looks
        * something like ['lang-js', /<[s]cript>(.+?)<\/script>/].  This may match
        * '<script>foo()<\/script>', which would cause the current decorator to
        * be called with '<script>' which would not match the same rule since
        * group 1 must not be empty, so it would be instead styled as PR_TAG by
        * the generic tag rule.  The handler registered for the 'js' extension would
        * then be called with 'foo()', and finally, the current decorator would
        * be called with '<\/script>' which would not match the original rule and
        * so the generic tag rule would identify it as a tag.
        *
        * Pattern must only match prefixes, and if it matches a prefix, then that
        * match is considered a token with the same style.
        *
        * Context is applied to the last non-whitespace, non-comment token
        * recognized.
        *
        * Shortcut is an optional string of characters, any of which, if the first
        * character, gurantee that this pattern and only this pattern matches.
        *
        * @param {Array} shortcutStylePatterns patterns that always start with
        *   a known character.  Must have a shortcut string.
        * @param {Array} fallthroughStylePatterns patterns that will be tried in
        *   order if the shortcut ones fail.  May have shortcuts.
        *
        * @return {function (Object)} a
        *   function that takes source code and returns a list of decorations.
        */
      function createSimpleLexer(shortcutStylePatterns, fallthroughStylePatterns) {
        var shortcuts = {};
        var tokenizer;
        (function () {
          var allPatterns = shortcutStylePatterns.concat(fallthroughStylePatterns);
          var allRegexs = [];
          var regexKeys = {};
          for (var i = 0, n = allPatterns.length; i < n; ++i) {
            var patternParts = allPatterns[i];
            var shortcutChars = patternParts[3];
            if (shortcutChars) {
              for (var c = shortcutChars.length; --c >= 0;) {
                shortcuts[shortcutChars.charAt(c)] = patternParts;
              }
            }
            var regex = patternParts[1];
            var k = '' + regex;
            if (!regexKeys.hasOwnProperty(k)) {
              allRegexs.push(regex);
              regexKeys[k] = null;
            }
          }
          allRegexs.push(/[\0-\uffff]/);
          tokenizer = combinePrefixPatterns(allRegexs);
        })();
    
        var nPatterns = fallthroughStylePatterns.length;
        var notWs = /\S/;
    
        /**
         * Lexes job.source and produces an output array job.decorations of style
         * classes preceded by the position at which they start in job.source in
         * order.
         *
         * @param {Object} job an object like {@code
         *    source: {string} sourceText plain text,
         *    basePos: {int} position of job.source in the larger chunk of
         *        sourceCode.
         * }
         */
        var decorate = function (job) {
          var sourceCode = job.source, basePos = job.basePos;
          /** Even entries are positions in source in ascending order.  Odd enties
            * are style markers (e.g., PR_COMMENT) that run from that position until
            * the end.
            * @type {Array.<number|string>}
            */
          var decorations = [basePos, PR_PLAIN];
          var pos = 0;  // index into sourceCode
          var tokens = sourceCode.match(tokenizer) || [];
          var styleCache = {};
    
          for (var ti = 0, nTokens = tokens.length; ti < nTokens; ++ti) {
            var token = tokens[ti];
            var style = styleCache[token];
            var match = void 0;
    
            var isEmbedded;
            if (typeof style === 'string') {
              isEmbedded = false;
            } else {
              var patternParts = shortcuts[token.charAt(0)];
              if (patternParts) {
                match = token.match(patternParts[1]);
                style = patternParts[0];
              } else {
                for (var i = 0; i < nPatterns; ++i) {
                  patternParts = fallthroughStylePatterns[i];
                  match = token.match(patternParts[1]);
                  if (match) {
                    style = patternParts[0];
                    break;
                  }
                }
    
                if (!match) {  // make sure that we make progress
                  style = PR_PLAIN;
                }
              }
    
              isEmbedded = style.length >= 5 && 'lang-' === style.substring(0, 5);
              if (isEmbedded && !(match && typeof match[1] === 'string')) {
                isEmbedded = false;
                style = PR_SOURCE;
              }
    
              if (!isEmbedded) { styleCache[token] = style; }
            }
    
            var tokenStart = pos;
            pos += token.length;
    
            if (!isEmbedded) {
              decorations.push(basePos + tokenStart, style);
            } else {  // Treat group 1 as an embedded block of source code.
              var embeddedSource = match[1];
              var embeddedSourceStart = token.indexOf(embeddedSource);
              var embeddedSourceEnd = embeddedSourceStart + embeddedSource.length;
              if (match[2]) {
                // If embeddedSource can be blank, then it would match at the
                // beginning which would cause us to infinitely recurse on the
                // entire token, so we catch the right context in match[2].
                embeddedSourceEnd = token.length - match[2].length;
                embeddedSourceStart = embeddedSourceEnd - embeddedSource.length;
              }
              var lang = style.substring(5);
              // Decorate the left of the embedded source
              appendDecorations(
                  basePos + tokenStart,
                  token.substring(0, embeddedSourceStart),
                  decorate, decorations);
              // Decorate the embedded source
              appendDecorations(
                  basePos + tokenStart + embeddedSourceStart,
                  embeddedSource,
                  langHandlerForExtension(lang, embeddedSource),
                  decorations);
              // Decorate the right of the embedded section
              appendDecorations(
                  basePos + tokenStart + embeddedSourceEnd,
                  token.substring(embeddedSourceEnd),
                  decorate, decorations);
            }
          }
          job.decorations = decorations;
        };
        return decorate;
      }
    
      /** returns a function that produces a list of decorations from source text.
        *
        * This code treats ", ', and ` as string delimiters, and \ as a string
        * escape.  It does not recognize perl's qq() style strings.
        * It has no special handling for double delimiter escapes as in basic, or
        * the tripled delimiters used in python, but should work on those regardless
        * although in those cases a single string literal may be broken up into
        * multiple adjacent string literals.
        *
        * It recognizes C, C++, and shell style comments.
        *
        * @param {Object} options a set of optional parameters.
        * @return {function (Object)} a function that examines the source code
        *     in the input job and builds the decoration list.
        */
      function sourceDecorator(options) {
        var shortcutStylePatterns = [], fallthroughStylePatterns = [];
        if (options['tripleQuotedStrings']) {
          // '''multi-line-string''', 'single-line-string', and double-quoted
          shortcutStylePatterns.push(
              [PR_STRING,  /^(?:\'\'\'(?:[^\'\\]|\\[\s\S]|\'{1,2}(?=[^\']))*(?:\'\'\'|$)|\"\"\"(?:[^\"\\]|\\[\s\S]|\"{1,2}(?=[^\"]))*(?:\"\"\"|$)|\'(?:[^\\\']|\\[\s\S])*(?:\'|$)|\"(?:[^\\\"]|\\[\s\S])*(?:\"|$))/,
               null, '\'"']);
        } else if (options['multiLineStrings']) {
          // 'multi-line-string', "multi-line-string"
          shortcutStylePatterns.push(
              [PR_STRING,  /^(?:\'(?:[^\\\']|\\[\s\S])*(?:\'|$)|\"(?:[^\\\"]|\\[\s\S])*(?:\"|$)|\`(?:[^\\\`]|\\[\s\S])*(?:\`|$))/,
               null, '\'"`']);
        } else {
          // 'single-line-string', "single-line-string"
          shortcutStylePatterns.push(
              [PR_STRING,
               /^(?:\'(?:[^\\\'\r\n]|\\.)*(?:\'|$)|\"(?:[^\\\"\r\n]|\\.)*(?:\"|$))/,
               null, '"\'']);
        }
        if (options['verbatimStrings']) {
          // verbatim-string-literal production from the C# grammar.  See issue 93.
          fallthroughStylePatterns.push(
              [PR_STRING, /^@\"(?:[^\"]|\"\")*(?:\"|$)/, null]);
        }
        if (options['hashComments']) {
          if (options['cStyleComments']) {
            // Stop C preprocessor declarations at an unclosed open comment
            shortcutStylePatterns.push(
                [PR_COMMENT, /^#(?:(?:define|elif|else|endif|error|ifdef|include|ifndef|line|pragma|undef|warning)\b|[^\r\n]*)/,
                 null, '#']);
            fallthroughStylePatterns.push(
                [PR_STRING,
                 /^<(?:(?:(?:\.\.\/)*|\/?)(?:[\w-]+(?:\/[\w-]+)+)?[\w-]+\.h|[a-z]\w*)>/,
                 null]);
          } else {
            shortcutStylePatterns.push([PR_COMMENT, /^#[^\r\n]*/, null, '#']);
          }
        }
        if (options['cStyleComments']) {
          fallthroughStylePatterns.push([PR_COMMENT, /^\/\/[^\r\n]*/, null]);
          fallthroughStylePatterns.push(
              [PR_COMMENT, /^\/\*[\s\S]*?(?:\*\/|$)/, null]);
        }
        if (options['regexLiterals']) {
          var REGEX_LITERAL = (
              // A regular expression literal starts with a slash that is
              // not followed by * or / so that it is not confused with
              // comments.
              '/(?=[^/*])'
              // and then contains any number of raw characters,
              + '(?:[^/\\x5B\\x5C]'
              // escape sequences (\x5C),
              +    '|\\x5C[\\s\\S]'
              // or non-nesting character sets (\x5B\x5D);
              +    '|\\x5B(?:[^\\x5C\\x5D]|\\x5C[\\s\\S])*(?:\\x5D|$))+'
              // finally closed by a /.
              + '/');
          fallthroughStylePatterns.push(
              ['lang-regex',
               new RegExp('^' + REGEXP_PRECEDER_PATTERN + '(' + REGEX_LITERAL + ')')
               ]);
        }
    
        var keywords = options['keywords'].replace(/^\s+|\s+$/g, '');
        if (keywords.length) {
          fallthroughStylePatterns.push(
              [PR_KEYWORD,
               new RegExp('^(?:' + keywords.replace(/\s+/g, '|') + ')\\b'), null]);
        }
    
        shortcutStylePatterns.push([PR_PLAIN,       /^\s+/, null, ' \r\n\t\xA0']);
        fallthroughStylePatterns.push(
            // TODO(mikesamuel): recognize non-latin letters and numerals in idents
            [PR_LITERAL,     /^@[a-z_$][a-z_$@0-9]*/i, null],
            [PR_TYPE,        /^@?[A-Z]+[a-z][A-Za-z_$@0-9]*/, null],
            [PR_PLAIN,       /^[a-z_$][a-z_$@0-9]*/i, null],
            [PR_LITERAL,
             new RegExp(
                 '^(?:'
                 // A hex number
                 + '0x[a-f0-9]+'
                 // or an octal or decimal number,
                 + '|(?:\\d(?:_\\d+)*\\d*(?:\\.\\d*)?|\\.\\d\\+)'
                 // possibly in scientific notation
                 + '(?:e[+\\-]?\\d+)?'
                 + ')'
                 // with an optional modifier like UL for unsigned long
                 + '[a-z]*', 'i'),
             null, '0123456789'],
            [PR_PUNCTUATION, /^.[^\s\w\.$@\'\"\`\/\#]*/, null]);
    
        return createSimpleLexer(shortcutStylePatterns, fallthroughStylePatterns);
      }
    
      var decorateSource = sourceDecorator({
            'keywords': ALL_KEYWORDS,
            'hashComments': true,
            'cStyleComments': true,
            'multiLineStrings': true,
            'regexLiterals': true
          });
    
      /** Breaks {@code job.source} around style boundaries in
        * {@code job.decorations} while re-interleaving {@code job.extractedTags},
        * and leaves the result in {@code job.prettyPrintedHtml}.
        * @param {Object} job like {
        *    source: {string} source as plain text,
        *    extractedTags: {Array.<number|string>} extractedTags chunks of raw
        *                   html preceded by their position in {@code job.source}
        *                   in order
        *    decorations: {Array.<number|string} an array of style classes preceded
        *                 by the position at which they start in job.source in order
        * }
        * @private
        */
      function recombineTagsAndDecorations(job) {
        var sourceText = job.source;
        var extractedTags = job.extractedTags;
        var decorations = job.decorations;
    
        var html = [];
        // index past the last char in sourceText written to html
        var outputIdx = 0;
    
        var openDecoration = null;
        var currentDecoration = null;
        var tagPos = 0;  // index into extractedTags
        var decPos = 0;  // index into decorations
        var tabExpander = makeTabExpander(window['PR_TAB_WIDTH']);
    
        var adjacentSpaceRe = /([\r\n ]) /g;
        var startOrSpaceRe = /(^| ) /gm;
        var newlineRe = /\r\n?|\n/g;
        var trailingSpaceRe = /[ \r\n]$/;
        var lastWasSpace = true;  // the last text chunk emitted ended with a space.
    
        // See bug 71 and http://stackoverflow.com/questions/136443/why-doesnt-ie7-
        var isIE678 = window['_pr_isIE6']();
        var lineBreakHtml = (
            isIE678
            ? (job.sourceNode.tagName === 'PRE'
               // Use line feeds instead of <br>s so that copying and pasting works
               // on IE.
               // Doing this on other browsers breaks lots of stuff since \r\n is
               // treated as two newlines on Firefox.
               ? (isIE678 === 6 ? '&#160;\r\n' :
                  isIE678 === 7 ? '&#160;<br>\r' : '&#160;\r')
               // IE collapses multiple adjacent <br>s into 1 line break.
               // Prefix every newline with '&#160;' to prevent such behavior.
               // &nbsp; is the same as &#160; but works in XML as well as HTML.
               : '&#160;<br />')
            : '<br />');
    
        // Look for a class like linenums or linenums:<n> where <n> is the 1-indexed
        // number of the first line.
        var numberLines = job.sourceNode.className.match(/\blinenums\b(?::(\d+))?/);
        var lineBreaker;
        if (numberLines) {
          var lineBreaks = [];
          for (var i = 0; i < 10; ++i) {
            lineBreaks[i] = lineBreakHtml + '</li><li class="L' + i + '">';
          }
          var lineNum = numberLines[1] && numberLines[1].length
              ? numberLines[1] - 1 : 0;  // Lines are 1-indexed
          html.push('<ol class="linenums"><li class="L', (lineNum) % 10, '"');
          if (lineNum) {
            html.push(' value="', lineNum + 1, '"');
          }
          html.push('>');
          lineBreaker = function () {
            var lb = lineBreaks[++lineNum % 10];
            // If a decoration is open, we need to close it before closing a list-item
            // and reopen it on the other side of the list item.
            return openDecoration
                ? ('</span>' + lb + '<span class="' + openDecoration + '">') : lb;
          };
        } else {
          lineBreaker = lineBreakHtml;
        }
    
        // A helper function that is responsible for opening sections of decoration
        // and outputing properly escaped chunks of source
        function emitTextUpTo(sourceIdx) {
          if (sourceIdx > outputIdx) {
            if (openDecoration && openDecoration !== currentDecoration) {
              // Close the current decoration
              html.push('</span>');
              openDecoration = null;
            }
            if (!openDecoration && currentDecoration) {
              openDecoration = currentDecoration;
              html.push('<span class="', openDecoration, '">');
            }
            // This interacts badly with some wikis which introduces paragraph tags
            // into pre blocks for some strange reason.
            // It's necessary for IE though which seems to lose the preformattedness
            // of <pre> tags when their innerHTML is assigned.
            // http://stud3.tuwien.ac.at/~e0226430/innerHtmlQuirk.html
            // and it serves to undo the conversion of <br>s to newlines done in
            // chunkify.
            var htmlChunk = textToHtml(
                tabExpander(sourceText.substring(outputIdx, sourceIdx)))
                .replace(lastWasSpace
                         ? startOrSpaceRe
                         : adjacentSpaceRe, '$1&#160;');
            // Keep track of whether we need to escape space at the beginning of the
            // next chunk.
            lastWasSpace = trailingSpaceRe.test(htmlChunk);
            html.push(htmlChunk.replace(newlineRe, lineBreaker));
            outputIdx = sourceIdx;
          }
        }
    
        while (true) {
          // Determine if we're going to consume a tag this time around.  Otherwise
          // we consume a decoration or exit.
          var outputTag;
          if (tagPos < extractedTags.length) {
            if (decPos < decorations.length) {
              // Pick one giving preference to extractedTags since we shouldn't open
              // a new style that we're going to have to immediately close in order
              // to output a tag.
              outputTag = extractedTags[tagPos] <= decorations[decPos];
            } else {
              outputTag = true;
            }
          } else {
            outputTag = false;
          }
          // Consume either a decoration or a tag or exit.
          if (outputTag) {
            emitTextUpTo(extractedTags[tagPos]);
            if (openDecoration) {
              // Close the current decoration
              html.push('</span>');
              openDecoration = null;
            }
            html.push(extractedTags[tagPos + 1]);
            tagPos += 2;
          } else if (decPos < decorations.length) {
            emitTextUpTo(decorations[decPos]);
            currentDecoration = decorations[decPos + 1];
            decPos += 2;
          } else {
            break;
          }
        }
        emitTextUpTo(sourceText.length);
        if (openDecoration) {
          html.push('</span>');
        }
        if (numberLines) { html.push('</li></ol>'); }
        job.prettyPrintedHtml = html.join('');
      }
    
      /** Maps language-specific file extensions to handlers. */
      var langHandlerRegistry = {};
      /** Register a language handler for the given file extensions.
        * @param {function (Object)} handler a function from source code to a list
        *      of decorations.  Takes a single argument job which describes the
        *      state of the computation.   The single parameter has the form
        *      {@code {
        *        source: {string} as plain text.
        *        decorations: {Array.<number|string>} an array of style classes
        *                     preceded by the position at which they start in
        *                     job.source in order.
        *                     The language handler should assigned this field.
        *        basePos: {int} the position of source in the larger source chunk.
        *                 All positions in the output decorations array are relative
        *                 to the larger source chunk.
        *      } }
        * @param {Array.<string>} fileExtensions
        */
      function registerLangHandler(handler, fileExtensions) {
        for (var i = fileExtensions.length; --i >= 0;) {
          var ext = fileExtensions[i];
          if (!langHandlerRegistry.hasOwnProperty(ext)) {
            langHandlerRegistry[ext] = handler;
          } else if ('console' in window) {
            console['warn']('cannot override language handler %s', ext);
          }
        }
      }
      function langHandlerForExtension(extension, source) {
        if (!(extension && langHandlerRegistry.hasOwnProperty(extension))) {
          // Treat it as markup if the first non whitespace character is a < and
          // the last non-whitespace character is a >.
          extension = /^\s*</.test(source)
              ? 'default-markup'
              : 'default-code';
        }
        return langHandlerRegistry[extension];
      }
      registerLangHandler(decorateSource, ['default-code']);
      registerLangHandler(
          createSimpleLexer(
              [],
              [
               [PR_PLAIN,       /^[^<?]+/],
               [PR_DECLARATION, /^<!\w[^>]*(?:>|$)/],
               [PR_COMMENT,     /^<\!--[\s\S]*?(?:-\->|$)/],
               // Unescaped content in an unknown language
               ['lang-',        /^<\?([\s\S]+?)(?:\?>|$)/],
               ['lang-',        /^<%([\s\S]+?)(?:%>|$)/],
               [PR_PUNCTUATION, /^(?:<[%?]|[%?]>)/],
               ['lang-',        /^<xmp\b[^>]*>([\s\S]+?)<\/xmp\b[^>]*>/i],
               // Unescaped content in javascript.  (Or possibly vbscript).
               ['lang-js',      /^<script\b[^>]*>([\s\S]*?)(<\/script\b[^>]*>)/i],
               // Contains unescaped stylesheet content
               ['lang-css',     /^<style\b[^>]*>([\s\S]*?)(<\/style\b[^>]*>)/i],
               ['lang-in.tag',  /^(<\/?[a-z][^<>]*>)/i]
              ]),
          ['default-markup', 'htm', 'html', 'mxml', 'xhtml', 'xml', 'xsl']);
      registerLangHandler(
          createSimpleLexer(
              [
               [PR_PLAIN,        /^[\s]+/, null, ' \t\r\n'],
               [PR_ATTRIB_VALUE, /^(?:\"[^\"]*\"?|\'[^\']*\'?)/, null, '\"\'']
               ],
              [
               [PR_TAG,          /^^<\/?[a-z](?:[\w.:-]*\w)?|\/?>$/i],
               [PR_ATTRIB_NAME,  /^(?!style[\s=]|on)[a-z](?:[\w:-]*\w)?/i],
               ['lang-uq.val',   /^=\s*([^>\'\"\s]*(?:[^>\'\"\s\/]|\/(?=\s)))/],
               [PR_PUNCTUATION,  /^[=<>\/]+/],
               ['lang-js',       /^on\w+\s*=\s*\"([^\"]+)\"/i],
               ['lang-js',       /^on\w+\s*=\s*\'([^\']+)\'/i],
               ['lang-js',       /^on\w+\s*=\s*([^\"\'>\s]+)/i],
               ['lang-css',      /^style\s*=\s*\"([^\"]+)\"/i],
               ['lang-css',      /^style\s*=\s*\'([^\']+)\'/i],
               ['lang-css',      /^style\s*=\s*([^\"\'>\s]+)/i]
               ]),
          ['in.tag']);
      registerLangHandler(
          createSimpleLexer([], [[PR_ATTRIB_VALUE, /^[\s\S]+/]]), ['uq.val']);
      registerLangHandler(sourceDecorator({
              'keywords': CPP_KEYWORDS,
              'hashComments': true,
              'cStyleComments': true
            }), ['c', 'cc', 'cpp', 'cxx', 'cyc', 'm']);
      registerLangHandler(sourceDecorator({
              'keywords': 'null true false'
            }), ['json']);
      registerLangHandler(sourceDecorator({
              'keywords': CSHARP_KEYWORDS,
              'hashComments': true,
              'cStyleComments': true,
              'verbatimStrings': true
            }), ['cs']);
      registerLangHandler(sourceDecorator({
              'keywords': JAVA_KEYWORDS,
              'cStyleComments': true
            }), ['java']);
      registerLangHandler(sourceDecorator({
              'keywords': SH_KEYWORDS,
              'hashComments': true,
              'multiLineStrings': true
            }), ['bsh', 'csh', 'sh']);
      registerLangHandler(sourceDecorator({
              'keywords': PYTHON_KEYWORDS,
              'hashComments': true,
              'multiLineStrings': true,
              'tripleQuotedStrings': true
            }), ['cv', 'py']);
      registerLangHandler(sourceDecorator({
              'keywords': PERL_KEYWORDS,
              'hashComments': true,
              'multiLineStrings': true,
              'regexLiterals': true
            }), ['perl', 'pl', 'pm']);
      registerLangHandler(sourceDecorator({
              'keywords': RUBY_KEYWORDS,
              'hashComments': true,
              'multiLineStrings': true,
              'regexLiterals': true
            }), ['rb']);
      registerLangHandler(sourceDecorator({
              'keywords': JSCRIPT_KEYWORDS,
              'cStyleComments': true,
              'regexLiterals': true
            }), ['js']);
      registerLangHandler(
          createSimpleLexer([], [[PR_STRING, /^[\s\S]+/]]), ['regex']);
    
      function applyDecorator(job) {
        var sourceCodeHtml = job.sourceCodeHtml;
        var opt_langExtension = job.langExtension;
    
        // Prepopulate output in case processing fails with an exception.
        job.prettyPrintedHtml = sourceCodeHtml;
    
        try {
          // Extract tags, and convert the source code to plain text.
          var sourceAndExtractedTags = extractTags(sourceCodeHtml);
          /** Plain text. @type {string} */
          var source = sourceAndExtractedTags.source;
          job.source = source;
          job.basePos = 0;
    
          /** Even entries are positions in source in ascending order.  Odd entries
            * are tags that were extracted at that position.
            * @type {Array.<number|string>}
            */
          job.extractedTags = sourceAndExtractedTags.tags;
    
          // Apply the appropriate language handler
          langHandlerForExtension(opt_langExtension, source)(job);
          // Integrate the decorations and tags back into the source code to produce
          // a decorated html string which is left in job.prettyPrintedHtml.
          recombineTagsAndDecorations(job);
        } catch (e) {
          if ('console' in window) {
            console['log'](e && e['stack'] ? e['stack'] : e);
          }
        }
      }
    
      function prettyPrintOne(sourceCodeHtml, opt_langExtension) {
        var job = {
          sourceCodeHtml: sourceCodeHtml,
          langExtension: opt_langExtension
        };
        applyDecorator(job);
        return job.prettyPrintedHtml;
      }
    
      function prettyPrint(opt_whenDone) {
        function byTagName(tn) { return document.getElementsByTagName(tn); }
        // fetch a list of nodes to rewrite
        var codeSegments = [byTagName('pre'), byTagName('code'), byTagName('xmp')];
        var elements = [];
        for (var i = 0; i < codeSegments.length; ++i) {
          for (var j = 0, n = codeSegments[i].length; j < n; ++j) {
            elements.push(codeSegments[i][j]);
          }
        }
        codeSegments = null;
    
        var clock = Date;
        if (!clock['now']) {
          clock = { 'now': function () { return (new Date).getTime(); } };
        }
    
        // The loop is broken into a series of continuations to make sure that we
        // don't make the browser unresponsive when rewriting a large page.
        var k = 0;
        var prettyPrintingJob;
    
        function doWork() {
          var endTime = (window['PR_SHOULD_USE_CONTINUATION'] ?
                         clock.now() + 250 /* ms */ :
                         Infinity);
          for (; k < elements.length && clock.now() < endTime; k++) {
            var cs = elements[k];
            // [JACOCO] 'prettyprint' -> 'source'
            if (cs.className && cs.className.indexOf('source') >= 0) {
              // If the classes includes a language extensions, use it.
              // Language extensions can be specified like
              //     <pre class="prettyprint lang-cpp">
              // the language extension "cpp" is used to find a language handler as
              // passed to PR_registerLangHandler.
              var langExtension = cs.className.match(/\blang-(\w+)\b/);
              if (langExtension) { langExtension = langExtension[1]; }
    
              // make sure this is not nested in an already prettified element
              var nested = false;
              for (var p = cs.parentNode; p; p = p.parentNode) {
                if ((p.tagName === 'pre' || p.tagName === 'code' ||
                     p.tagName === 'xmp') &&
                    // [JACOCO] 'prettyprint' -> 'source'
                    p.className && p.className.indexOf('source') >= 0) {
                  nested = true;
                  break;
                }
              }
              if (!nested) {
                // fetch the content as a snippet of properly escaped HTML.
                // Firefox adds newlines at the end.
                var content = getInnerHtml(cs);
                content = content.replace(/(?:\r\n?|\n)$/, '');
    
                // do the pretty printing
                prettyPrintingJob = {
                  sourceCodeHtml: content,
                  langExtension: langExtension,
                  sourceNode: cs
                };
                applyDecorator(prettyPrintingJob);
                replaceWithPrettyPrintedHtml();
              }
            }
          }
          if (k < elements.length) {
            // finish up in a continuation
            setTimeout(doWork, 250);
          } else if (opt_whenDone) {
            opt_whenDone();
          }
        }
    
        function replaceWithPrettyPrintedHtml() {
          var newContent = prettyPrintingJob.prettyPrintedHtml;
          if (!newContent) { return; }
          var cs = prettyPrintingJob.sourceNode;
    
          // push the prettified html back into the tag.
          if (!isRawContent(cs)) {
            // just replace the old html with the new
            cs.innerHTML = newContent;
          } else {
            // we need to change the tag to a <pre> since <xmp>s do not allow
            // embedded tags such as the span tags used to attach styles to
            // sections of source code.
            var pre = document.createElement('PRE');
            for (var i = 0; i < cs.attributes.length; ++i) {
              var a = cs.attributes[i];
              if (a.specified) {
                var aname = a.name.toLowerCase();
                if (aname === 'class') {
                  pre.className = a.value;  // For IE 6
                } else {
                  pre.setAttribute(a.name, a.value);
                }
              }
            }
            pre.innerHTML = newContent;
    
            // remove the old
            cs.parentNode.replaceChild(pre, cs);
            cs = pre;
          }
        }
    
        doWork();
      }
    
      window['PR_normalizedHtml'] = normalizedHtml;
      window['prettyPrintOne'] = prettyPrintOne;
      window['prettyPrint'] = prettyPrint;
      window['PR'] = {
            'combinePrefixPatterns': combinePrefixPatterns,
            'createSimpleLexer': createSimpleLexer,
            'registerLangHandler': registerLangHandler,
            'sourceDecorator': sourceDecorator,
            'PR_ATTRIB_NAME': PR_ATTRIB_NAME,
            'PR_ATTRIB_VALUE': PR_ATTRIB_VALUE,
            'PR_COMMENT': PR_COMMENT,
            'PR_DECLARATION': PR_DECLARATION,
            'PR_KEYWORD': PR_KEYWORD,
            'PR_LITERAL': PR_LITERAL,
            'PR_NOCODE': PR_NOCODE,
            'PR_PLAIN': PR_PLAIN,
            'PR_PUNCTUATION': PR_PUNCTUATION,
            'PR_SOURCE': PR_SOURCE,
            'PR_STRING': PR_STRING,
            'PR_TAG': PR_TAG,
            'PR_TYPE': PR_TYPE
          };
    })();