Run results for: flatMap vs for...of

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.36

Browser: Chrome 135

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Benchmark engine: Benchmark.js

for of

187K/s

forEach

72K/s

flatMap

30K/s

View exact numbers

Script Preparation code:

xs = new Array(1000).fill("world")

Tests:

flatMap
xs.flatMap((x) => ["hello", x])
for of
const out = [] for (const x of xs) { out.push("hello"); out.push(x); } return out
forEach
const out = [] xs.forEach( (x) => { out.push("hello"); out.push(x); }) return out;