delete vs undefined vs null

JavaScript performance comparison

Revision 32 of this test case created by Arjun

Preparation code

<script>
  o = {};
  o.p = 1;
  
  function reset() {
   o.p = 1;
  }
</script>
    

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Testing in CCBot 2.0.0 / Other 0.0.0
Test Ops/sec
delete object.property
delete o.p;
reset();
pending…
delete object["property"]
delete o["p"];
reset();
pending…
object.property = undefined
o.p = undefined;
reset();
pending…
object["property"] = undefined
o["p"] = undefined;
reset();
pending…
object.property = null
o.p = null;
reset();
pending…
object["property"] = null
o["p"] = null;
reset();
pending…
Object.defineProperty undefined non-enumerable
  Object.defineProperty(o, "p", {
    enumerable: false,
    value: undefined
  });
pending…

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