Benchmark: filtering with Array.prototype.flatMap vs for of loop vs Array.prototype.map + Array.prototype.filter

Script Preparation code:

numbers = [
    1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
    1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
    1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
    1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
    1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
    1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
    1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
    1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
    1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
    1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
];

Tests:

Array.prototype.flatMap
const result = numbers.flatMap(num => num % 2 === 0 ? [num + 100] : null);
for of loop
const result = []; for (const num of numbers) { if (num % 2 === 0) { result.push(num + 100); } }
Array.prototype.map + Array.prototype.filter
const result = numbers .filter(num => num % 2 === 0 ? [num] : []) .map(num => num + 100);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array.prototype.flatMap
for of loop
Array.prototype.map + Array.prototype.filter

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 9 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.4 Safari/605.1.15

Browser/OS: Safari 16 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Array.prototype.flatMap	715086.3 Ops/sec
for of loop	2736137.0 Ops/sec
Array.prototype.map + Array.prototype.filter	420395.3 Ops/sec

filtering with Array.prototype.flatMap vs for of loop vs Array.prototype.map + Array.prototype.filter (version: 1)

Comparing performance of: Array.prototype.flatMap vs for of loop vs Array.prototype.map + Array.prototype.filter

Created: 9 months ago by: Registered User

Jump to the latest result

Array.prototype.flatMap

for of loop

Array.prototype.map + Array.prototype.filter

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A