Simple JS running time profiler

js-time-profiler.js

/** 
 * Profiling (running time). For dev purpose only. 
 */
(function() {
	window._profiler = {
		'profiles': []
	}; 
	_profiler.time = function(name) {
		_profiler.profiles[name] = new Date();
	};

	_profiler.timeEnd = function(name) {
		var diff = new Date() - _profiler.profiles[name];
		print(diff);
	}; 

	var print = function (val) {
		// Only print the timer when jsprofile is present in the url querystring
		if(/jsprofile/.test(window.location.search)) {
			alert(val); 
			
			// Self-rewrite so that from the second time it doesn't need check url string
			print = function(val) {
				alert(val);	
			}
		}
	}
})();