code: function(tag) {
  		if (!tag) {
  			// create a document fragment to hold multiple-root elements
  			if (document.createDocumentFragment) {
  				return document.createDocumentFragment();
  			}
  
  			tag = '';
  
  		} else if (tag.charAt(0) === '!') {
  			return document.createComment(tag === '!' ? '' : tag.substr(1)+' ');
  		}
  
  		return document.createElement(tag);
  	}
docs: Creates a DOM element
  
  @private
  @param {string} tag The element's tag name
  @return {Node}