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Run results for:
flatMap vs for in vs forEach
Comparing performance of: flatMap vs for of
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Embed Benchmark Result
<iframe src="https://measurethat.net/Embed?id=511546" width="100%" height="500px"></iframe>
Run details:
User agent:
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36
Browser:
Chrome 122
Operating system:
Mac OS X 10.15.7
Device Platform:
Desktop
Date tested:
2 years ago
for...in
25.9M/s
forEach
7K/s
flatMap
350/s
View exact numbers
Test name
Executions per second
✓
for...in
25,856,112 Ops/sec
forEach
7,220 Ops/sec
flatMap
350 Ops/sec
HTML Preparation code:
var n = 100000
Script Preparation code:
var n = 100000
Tests:
flatMap
[...Array(n)].flatMap((x,i) => [++i,i++])
forEach
let res = []; Array(n).forEach((_,i) => res.push(i+1, i+1))
for...in
let res = []; for (const el in n) { res.push(el, el); }