Run results for: array[array.length - 1] vs array.at(-1) v2

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 18_3_2 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) FxiOS/136.2 Mobile/15E148 Safari/605.1.15

Browser: Mobile Safari 18

Operating system: iOS 18.3.2

Device Platform: Mobile

Date tested: one year ago

array.at(-1)

483.4M/s

array[array.length - 1]

456.6M/s

array[array.length - 1] fn

427.3M/s

array.at(-1) fn

394.8M/s

View exact numbers

Test name	Executions per second
✓ array.at(-1)	483,425,184 Ops/sec
array[array.length - 1]	456,637,088 Ops/sec
array[array.length - 1] fn	427,288,032 Ops/sec
array.at(-1) fn	394,820,736 Ops/sec

Script Preparation code:

var array = [1, 2, 3];

function last1(array) {
    return array[array.length - 1]
}

function last2(array) {
    return array.at(-1)
}

Tests:

array[array.length - 1]
var d = array[array.length - 1];
array.at(-1)
var z = array.at(-1);
array[array.length - 1] fn
var x = last1(array);
array.at(-1) fn
var y = last2(array);