Run results for: map+filter options

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser: Chrome 114

Operating system: Linux

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
naive map + filter	414714.4 Ops/sec
manual for loop	5582.9 Ops/sec
manual for loop fixed size result	5623.9 Ops/sec
foreach	1157850.1 Ops/sec
for of	9584.7 Ops/sec

HTML Preparation code:

<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.11/lodash.core.js"></script>

Script Preparation code:

var arr = (new Array(1000)).map((_, i) => i);

Tests:

naive map + filter
var result = arr.map((x) => x % 2 === 0 ? x : null).filter(x => x !== null);
manual for loop
var result = []; for (var i = 0; i < arr.length; i++) { var x = arr[i]; if (x % 2 === 0) { result.push(x); } }
manual for loop fixed size result
var result = new Array(arr.length); var next = 0; for (var i = 0; i < arr.length; i++) { var x = arr[i]; if (x % 2 === 0) { result[next++] = x; } } result = result.slice(0, next);
foreach
var result = []; arr.forEach((x) => { if (x % 2 === 0) { result.push(x); } });
for of
var result = []; for (var x of arr) { if (x % 2 === 0) { result.push(x); } }