Run results for: Cloning.

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36

Browser: Chrome 111

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
obj	439.1 Ops/sec
set	2209.1 Ops/sec
map	1753.0 Ops/sec
array	434808.3 Ops/sec

Script Preparation code:

const size = 10000;
var obj = {};
var set = new Set();
var map = new Map();
var arr = [];

for (let i=0; i < size; i++) {
  const item = `item${i}`;
  obj[item] = true;
  set.add(item);
  map.set(item, true);
  arr.push(item);
 
}

Tests:

obj
let copy = {...obj} delete copy.item5000
set
let copy = new Set(set) copy.delete("item5000")
map
let copy = new Map(map) copy.set("item5000", undefined);
array
let copy = [...arr] copy[5000] = undefined;

obj

set

map

array