hijs.js

(function (hijs) {
//
// hijs - JavaScript Syntax Highlighter
//
// Copyright (c) 2010 Alexis Sellier
//

// All elements which match this will be syntax highlighted.
var selector = hijs || 'code';

var keywords = ('var function if else for while break switch case do new null in with void '
               +'continue delete return this true false throw catch typeof with instanceof script test module').split(' '),
    special  = ('eval window document undefined NaN Infinity parseInt parseFloat '
               +'encodeURI decodeURI encodeURIComponent decodeURIComponent $').split(' ');

// Syntax definition
// The key becomes the class name of the <span>
// around the matched block of code.
var syntax = [
  ['comment', /(\/\*(?:[^*\n]|\*+[^\/*])*\*+\/)/g],
  ['comment', /(\/\/[^\n]*)/g],
  ['string' , /("(?:(?!")[^\\\n]|\\.)*"|'(?:(?!')[^\\\n]|\\.)*')/g],
  ['regexp' , /(\/.+\/[mgi]*)(?!\s*\w)/g],
  ['class'  , /\b([A-Z][a-zA-Z]+)\b/g],
  ['number' , /\b([0-9]+(?:\.[0-9]+)?)\b/g],
  ['keyword', new(RegExp)('\\b(' + keywords.join('|') + ')\\b', 'g')],
  ['special', new(RegExp)('\\b(' + special.join('|') + ')\\b', 'g')]
];
  
var nodes, table = {};

function runhijs(){
  nodes = [];
  table = {};
  
  if (/^[a-z]+$/.test(selector)) {
      nodes = document.getElementsByTagName(selector);
  } else if (/^\.[\w-]+$/.test(selector)) {
      nodes = document.getElementsByClassName(selector.slice(1));
  } else if (document.querySelectorAll) {
      nodes = document.querySelectorAll(selector);
  } else {
      nodes = [];
  }

  for (var i = 0, children; i < nodes.length; i++) {
      children = nodes[i].childNodes;

      for (var j = 0, str; j < children.length; j++) {
          code = children[j];

          if (code.length >= 0) { // It's a text node
              // Don't highlight command-line snippets
              if (! /^\$/.test(code.nodeValue.trim())) {
                  syntax.forEach(function (s) {
                      var k = s[0], v = s[1];
                      code.nodeValue = code.nodeValue.replace(v, function (_, m) {
                          return '\u00ab' + encode(k) + '\u00b7'
                                          + encode(m) +
                                 '\u00b7' + encode(k) + '\u00bb';
                      });
                  });
              }
          }
      }
  }
  for (var i = 0; i < nodes.length; i++) {
      nodes[i].innerHTML =
          nodes[i].innerHTML.replace(/\u00ab(.+?)\u00b7(.+?)\u00b7\1\u00bb/g, function (_, name, value) {
              value = value.replace(/\u00ab[^\u00b7]+\u00b7/g, '').replace(/\u00b7[^\u00bb]+\u00bb/g, '');
              return '<span class="' + decode(name) + '">' + escape(decode(value)) + '</span>';
      });
  }
}

function escape(str) {
    return str.replace(/</g, '&lt;').replace(/>/g, '&gt;');
}

// Encode ASCII characters to, and from Braille
function encode (str, encoded) {
    table[encoded = str.split('').map(function (s) {
        if (s.charCodeAt(0) > 127) { return s }
        return String.fromCharCode(s.charCodeAt(0) + 0x2800);
    }).join('')] = str;
    return encoded;
}
function decode (str) {
    if (str in table) {
        return table[str];
    } else {
        return str.trim().split('').map(function (s) {
            if (s.charCodeAt(0) - 0x2800 > 127) { return s }
            return String.fromCharCode(s.charCodeAt(0) - 0x2800);
        }).join('');
    }
}

window.runhijs = runhijs;

})(window.hijs);