docs: function addAttributeInElement( node, elementTarget, separator ) {
  
  		var mardownClassesInElementsRegex = new RegExp( separator, 'mg' );
  		var mardownClassRegex = new RegExp( "([^\"= ]+?)=\"([^\"=]+?)\"", 'mg' );
  		var nodeValue = node.nodeValue;
  		if( matches = mardownClassesInElementsRegex.exec( nodeValue ) ) {
  
  			var classes = matches[1];
  			nodeValue = nodeValue.substring( 0, matches.index ) + nodeValue.substring( mardownClassesInElementsRegex.lastIndex );
  			node.nodeValue = nodeValue;
  			while( matchesClass = mardownClassRegex.exec( classes ) ) {
  				elementTarget.setAttribute( matchesClass[1], matchesClass[2] );
  			}
  			return true;
  		}
  		return false;
  	}