( function()
{
	jQuery.fn.ancestor = function( expr )
	{
		if( ! expr )
		{
			return $( this ).parent();
		}
		
		var elem = this.get( 0 ).parentNode;
		
		while( elem )
		{
			if( $( elem ).is( expr ) )
			{
				return $( elem );
			}
			
			elem = elem.parentNode
		};
		
		return $();
	};
} )( jQuery );