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

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:109.0) Gecko/20100101 Firefox/115.0

Browser: Firefox 115

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
filter().map()	469.3 Ops/sec
flatMap()	419.2 Ops/sec

Script Preparation code:

var arr = [];
var i = 0;

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

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

Tests:

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