Run results for: flatMap vs reduce vs map - MeasureThat.net

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/134.0.0.0 Safari/537.36 Edg/134.0.0.0

Browser: Chrome 134

Operating system: Windows

Device Platform: Desktop

Date tested: one month ago

Test name	Executions per second
reduce	26163.3 Ops/sec
flatMap	10371.4 Ops/sec
map	10777.5 Ops/sec
foreach	26271.8 Ops/sec
for of	27676.5 Ops/sec

Script Preparation code:

var arr = Array(100).fill({
    portfolios: Array(100).fill(null)
});

Tests:

reduce
arr.reduce((acc, x) => {acc.push(...x.portfolios); return acc;}, [])
flatMap
arr.flatMap(x => x.portfolios)
map
arr.map(x => x.portfolios).flat()
foreach
const result = []; arr.forEach(x => result.push(...x.portfolios));
for of
const result = []; for(const x of arr) result.push(...x.portfolios);