return (date || Date.now()) - this; 
return (date || new Date()) - this; 
Date.prototype.getElapsed = function (date) {    return (date || Date.now()) - this;};
4137	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/4137/4f9e9875c3d94ca9d46a8f76c66c5e872597ccff/core-debug.js/buggy/core-debug.js