Run results for: flatMap() vs filter().map()

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 17_1_2 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.1.2 Mobile/15E148 Safari/604.1

Browser: Mobile Safari 17

Operating system: iOS 17.1.2

Device Platform: Mobile

Date tested: 2 years ago

flatMap()

2K/s

filter().map()

377/s

View exact numbers

Test name	Executions per second
✓ flatMap()	1,726 Ops/sec
filter().map()	377 Ops/sec

Script Preparation code:

var arr = [];
var i = 0;

while (i <= 1E5) arr[i] = i++;

Tests:

filter().map()
arr.filter(x => x % 3).map(x => x/100)
flatMap()
arr.flatMap(x => x % 3 ? x/100 : [])

Run results for: flatMap() vs filter().map()

flatMap vs filter map

filter().map()

flatMap()