jsBenchmarker

Source of "collections_iteration"

(function(){
	var hash = {}, arr = [ ], times = 3e5;
	for( var i=0; i < times; i++ )
		hash[i] = arr[i] = i;
	
	Benchmarker().compare({ attempts:5, times:1 }, {
		'index hash': function(){
			for( var i=0; i < times; i++ )
				hash[i];
		},	
		'index arr':function(){
			for( var i=0; i < times; i++ )
				arr[i];
		},	
		'hash hash': function(){
			for( var i in hash )
				hash[i];
		},	
		'hash arr':function(){
			for( var i in arr )
				arr[i];
		}
	});
})();

/**
 * Conclusions
 *	Iterating an array and a array-like hashmap, takes the same time
 *	for...in is much slower than index-based for.
 */