gistfile1.js

/*
Usage:

t = timer();
t('start')
…some slow script…
t('checkpoint');
…some slow script…
list = t('checkpoint2');

alert(list) => [start:0,  checkpoint:100, checkpoint2:1302 ]

*/

var timer = function(){
	
	var d = new Date();
	var start = d.getTime();
	
	var ts = [];
	
	return function(mark){
		var d = new Date();
		var t = d.getTime() - start;
		if(mark){
			ts.push(mark + ':' + t);
		} else {
			ts.push(t);
		}
		return ts;
	}
}