Run results for: Benchmark: flatMap vs reduce vs while vs foreach - MeasureThat.net

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:94.0) Gecko/20100101 Firefox/94.0

Browser: Firefox 94

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
flatMap	12606.9 Ops/sec
reduce	54.8 Ops/sec
while	21719.0 Ops/sec
foreach	136160.7 Ops/sec

Script Preparation code:

var n = 1000

Tests:

flatMap
[...Array(n)].flatMap((x,i) => [++i,i++])
reduce
[...Array(n).keys()].reduce((acc, cur) => [...acc, ++cur, cur++], [])
while
let res = [], i=0; while(n>i++) res.push(i, i);
foreach
let res = []; Array(n).forEach((_,i) => res.push(i+1, i+1))

;