Run results for: Reduce vs Loop (partition) 1000

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/112.0.0.0 Safari/537.36

Browser: Chrome 112

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Script Preparation code:

arr = [...Array(1000)].map((v, i) => (i + 1))
filter = (el) => el % 2 === 0

Tests:

Reduce
arr.reduce( ([pass, fail], elem) => { if (filter(elem)) { return [[...pass, elem], fail]; } else { return [pass, [...fail, elem]]; } }, [[], []], );
Regular loop
const pass = []; const fail = []; for (let i = 0; i < arr.length; i++) { if (filter(arr[i])) { pass.push(arr[i]); } else { fail.push(arr[i]); } }
Of loop
const pass = []; const fail = []; for (const item of arr) { if (filter(item)) { pass.push(item); } else { fail.push(item); } }
Of loop (let not const)
const pass = []; const fail = []; for (let item of arr) { if (filter(item)) { pass.push(item); } else { fail.push(item); } }