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https://jsperf.com/negative-modulo/2
Can be accessed at:
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Is it faster to use the native forEach or just loop with for?
Inspired by Adrian Sutton's tests at: http://www.symphonious.net/2010/10/09/javascript-performance-for-vs-foreach/
This one adds random floating point numbers to see if the loop overhead is significant at all in the face of standard work.
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js">
</script>
var i,
value,
length,
values = [],
sum = 0,
context = values;
for (i = 0; i < 10000; i++) {
values[i] = Math.random();
}
function add(val) {
sum += val;
}
Array.prototype.forEachMDN = function(fun /*, thisArg */)
{
"use strict";
if (this === void 0 || this === null)
throw new TypeError();
var t = Object(this);
var len = t.length >>> 0;
if (typeof fun !== "function")
throw new TypeError();
var thisArg = arguments.length >= 2 ? arguments[1] : void 0;
for (var i = 0; i < len; i++)
{
if (i in t)
fun.call(thisArg, t[i], i, t);
}
};
i = 0;
value = 0;
length = 0;
values = [];
sum = 0;
Ready to run.
Test | Ops/sec | |
---|---|---|
forEach |
| ready |
for loop, simple |
| ready |
for loop, cached length |
| ready |
for loop, reverse |
| ready |
for loop, cached length, callback |
| ready |
for loop, cached length, callback.call |
| ready |
$.each |
| ready |
for ... in |
| ready |
for loop, reverse, decrement condition |
| ready |
for loop, reverse, pre-decrement |
| ready |
for loop, assignment condition |
| ready |
for loop, assignment condition, reversed |
| ready |
for loop, assignment condition, callback |
| ready |
for loop, assignment condition, callback.call |
| ready |
MDN forEach polyfill |
| ready |
You can edit these tests or add more tests to this page by appending /edit to the URL.