code: function replaceRenderer(md, renderer) {
    var openMethodName = renderer.fullName + "_open";
    replacedMethods[openMethodName] = md.renderer.rules[openMethodName];
  
    md.renderer.rules[openMethodName] = function (tokens, idx) {
      var classy, result;
  
      // first get the result as per the original method we replaced
      result = replacedMethods[openMethodName].apply(null, arguments).trim();
  
      if (renderer.inline) {
        classy = getClassyFromInlineElement(tokens, idx, renderer.fullName);
      } else {
        classy = getClassyFromBlockElement(tokens, idx, renderer.fullName);
      }
  
      if (classy) {
        result = result.replace(new RegExp("<" + renderer.pattern), "$& class=\"" + classy.content + "\"");
      }
  
      return result;
    };
  }
docs: replace all rules that we want to enable classy on