Run results for: set.has vs. Object key in lookup

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.3.1 Safari/605.1.15

Browser: Safari 17

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

set.has

460.7M/s

key in

366.7M/s

View exact numbers

Test name	Executions per second
✓ set.has	460,671,392 Ops/sec
key in	366,664,608 Ops/sec

Script Preparation code:

var a = new Set([1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);
var b = {1: true, 2: true, 3: true, 4: true, 5: true, 6: true, 7: true, 8: true, 9: true, 10: true}

Tests:

set.has
return a.has(9)
key in
return 9 in b;