Run results for: fill then map (with null/undefined/"") vs array.from - MeasureThat.net

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36

Browser: Chrome 120

Operating system: Linux

Device Platform: Desktop

Date tested: 2 years ago

.fill("").map()

3.3M/s

.fill(null).map()

3.3M/s

.fill(true).map()

3.3M/s

.fill(undefined).map()

3.3M/s

Array.from().map()

430K/s

Array.from() only

420K/s

View exact numbers

Test name	Executions per second
✓ .fill("").map()	3,305,867 Ops/sec
.fill(null).map()	3,303,410 Ops/sec
.fill(true).map()	3,278,488 Ops/sec
.fill(undefined).map()	3,278,441 Ops/sec
Array.from().map()	429,574 Ops/sec
Array.from() only	419,898 Ops/sec

Tests:

Array.from() only
Array.from({ length: 100 }, (_, i) => i+i);
Array.from().map()
Array.from({ length: 100 }).map((_, i) => i+i);
.fill("").map()
Array(100).fill("").map((_, i) => i+i);
.fill(null).map()
Array(100).fill(null).map((_, i) => i+i);
.fill(undefined).map()
Array(100).fill(null).map((_, i) => i+i);
.fill(true).map()
Array(100).fill(true).map((_, i) => i+i);