Run results for: indexed for vs for...of

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/144.0.0.0 Safari/537.36

Browser: Chrome 144

Operating system: Windows

Device Platform: Desktop

Date tested: 6 months ago

indexed for

90/s

for...of

19/s

View exact numbers

Test name	Executions per second
✓ indexed for	90 Ops/sec
for...of	19 Ops/sec

Script Preparation code:

"use strict";

const LEN  = 1 << 18; // 262,144
const REPS = 32;

// Deterministic PRNG (LCG)
let seed = 0x12345678 | 0;
const nextInt = () => (seed = (Math.imul(seed, 1664525) + 1013904223) | 0);

const data = new Int32Array(LEN);
for (let i = 0; i < LEN; i++) data[i] = nextInt();

globalThis.__benchSink = 0;

const DATA = data;
const N = LEN;
const R = REPS;

Tests:

indexed for
let sum = 0; for (let r = 0; r < R; r++) { for (let i = 0; i < N; i++) { sum += DATA[i]; } } globalThis.__benchSink = sum;
for...of
let sum = 0; for (let r = 0; r < R; r++) { for (const v of DATA) { sum += v; } } globalThis.__benchSink = sum;