Run results for: Array: delete vs undefined

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36

Browser: Chrome 111

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
Delete array element	78.6 Ops/sec
Set array element to undefined	39.1 Ops/sec

Script Preparation code:

var arr1 = [];
var arr2 = [];
for(let i = 0; i < 100000; i++) {
  arr1[i] = i;
  arr2[i] = i;
}

Tests:

Delete array element
for(let i = 0; i < 100000; i++) { delete arr1[i]; }
Set array element to undefined
for(let i = 0; i < 100000; i++) { arr2[i] = undefined; }