add: if (!action) { return value; } 
context: HopObject.prototype.link_filter = function(value, param, action) {   return renderLink(param, action, value, this);};
meta: 993	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/993/3d0fae4302b944a61894fbad9cb3eb06f72984a3/HopObject.js/buggy/code/HopObject/HopObject.js