showdown: Support for code highlighting in githubCodeBlocks

Do you plan to add support for syntax highlighting in githubCodeBlocks?

Something like this:

if (options.highlight) {
  codeblock = options.highlight(codeblock, language) || codeblock;
}

I can send PR.

About this issue

Original URL
State: closed
Created 9 years ago
Comments: 17 (6 by maintainers)

Most upvoted comments

Making an extension for code highlighting would be kind of easy with the new showdown’s extended RegExp engine.

example using https://highlightjs.org/ library:

showdown.extension('codehighlight', function() {
  function htmlunencode(text) {
    return (
      text
        .replace(/&amp;/g, '&')
        .replace(/&lt;/g, '<')
        .replace(/&gt;/g, '>')
      );
  }
  return [
    {
      type: 'output',
      filter: function (text, converter, options) {
        // use new shodown's regexp engine to conditionally parse codeblocks
        var left  = '<pre><code\\b[^>]*>',
            right = '</code></pre>',
            flags = 'g',
            replacement = function (wholeMatch, match, left, right) {
              // unescape match to prevent double escaping
              match = htmlunencode(match);
              return left + hljs.highlightAuto(match).value + right;
            };
        return showdown.helper.replaceRecursiveRegExp(text, replacement, left, right, flags);
      }
    }
  ];
});

tivie on Jan 4, 2016