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Array.from().forEach vs for...in

Benchmark created by Becky on April 13, 2017

Preparation HTML

<ol class="items">
   <li>Lorem ipsum dolor sit amet, consectetuer adipiscing elit.</li>
   <li>Aliquam tincidunt mauris eu risus.</li>
   <li>Vestibulum auctor dapibus neque.</li>
<li>Lorem ipsum dolor sit amet, consectetuer adipiscing elit.</li>
   <li>Aliquam tincidunt mauris eu risus.</li>
   <li>Vestibulum auctor dapibus neque.</li>
<li>Lorem ipsum dolor sit amet, consectetuer adipiscing elit.</li>
   <li>Aliquam tincidunt mauris eu risus.</li>
   <li>Vestibulum auctor dapibus neque.</li>
<li>Lorem ipsum dolor sit amet, consectetuer adipiscing elit.</li>
   <li>Aliquam tincidunt mauris eu risus.</li>
   <li>Vestibulum auctor dapibus neque.</li>
<li>Lorem ipsum dolor sit amet, consectetuer adipiscing elit.</li>
   <li>Aliquam tincidunt mauris eu risus.</li>
   <li>Vestibulum auctor dapibus neque.</li>
<li>Lorem ipsum dolor sit amet, consectetuer adipiscing elit.</li>
   <li>Aliquam tincidunt mauris eu risus.</li>
   <li>Vestibulum auctor dapibus neque.</li>
<li>Lorem ipsum dolor sit amet, consectetuer adipiscing elit.</li>
   <li>Aliquam tincidunt mauris eu risus.</li>
   <li>Vestibulum auctor dapibus neque.</li>
<li>Lorem ipsum dolor sit amet, consectetuer adipiscing elit.</li>
   <li>Aliquam tincidunt mauris eu risus.</li>
   <li>Vestibulum auctor dapibus neque.</li>
<li>Lorem ipsum dolor sit amet, consectetuer adipiscing elit.</li>
   <li>Aliquam tincidunt mauris eu risus.</li>
   <li>Vestibulum auctor dapibus neque.</li>
<li>Lorem ipsum dolor sit amet, consectetuer adipiscing elit.</li>
   <li>Aliquam tincidunt mauris eu risus.</li>
   <li>Vestibulum auctor dapibus neque.</li>
</ol>

Setup

forEach = Array.prototype.forEach;

Test runner

Ready to run.

Test Ops/sec

Array.from().forEach()

Testing in
Test	Ops/sec
Array.from().forEach()	`const items = Array.from(document.querySelectorAll('.items li')).forEach(item => { /* do something */ });`	ready
for...in	`const items = document.querySelectorAll('.items li'); for (item in items) { // do something }`	ready

const items = Array.from(document.querySelectorAll('.items li')).forEach(item => { /* do something */ });

ready

for...in

const items = document.querySelectorAll('.items li');

for (item in items) {
 // do something
}

ready

Revisions

You can edit these tests or add more tests to this page by appending /edit to the URL.

Revision 1: published by Becky on April 13, 2017