Run results for: flatMap() vs filter().map() vs for loop accumulator vs forEach

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.36

Browser: Chrome 135

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

for loop

1K/s

forEach

813/s

flatMap()

582/s

filter().map()

468/s

View exact numbers

Script Preparation code:

var arr = [];
var i = 0;

while (i <= 1E5) arr[i] = i++;

Tests:

filter().map()
arr.filter(x => x % 30).map(x => x/100)
flatMap()
arr.flatMap(x => x % 30 ? x/100 : [])
for loop
var accum = []; for (let i=0; i < arr.length; i++) { const x = arr[i]; if (x % 30) { accum.push(x/100) } }
forEach
var accum = []; arr.forEach((x) => { if (x % 30){ accum.push(x/100) } })