code: function ( d )
  		{
  			// V8 will remove any unknown characters at the start of the expression,
  			// leading to false matches such as `$245.12` being a valid date. See
  			// forum thread 18941 for detail.
  			if ( d && ! _re_date_start.test(d) ) {
  				return null;
  			}
  			var parsed = Date.parse(d);
  			return (parsed !== null && !isNaN(parsed)) || _empty(d) ? 'date' : null;
  		}
docs: Dates (only those recognised by the browser's Date.parse)