Run details:
Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/130.0.0.0 Safari/537.36
Chrome 130
Mac OS X 10.15.7
Desktop
5 months ago
Test name Executions per second
Spread 2563.2 Ops/sec
for loop 2229.9 Ops/sec
Script Preparation code:
AخA
 
const setA = new Set();
const setB = new Set();
for(i=0; i<10000; i++){
    setA.add(i.toString());
    setB.add((i + 10000).toString())
}
Tests:
  • Spread

     
    new Set([...setA, ...setB]);
  • for loop

     
    for (const value of setB) {
      setA.add(value);
    }