delete vs undefined vs null

JavaScript performance comparison

Revision 27 of this test case created by Gary

Preparation code


      
      <script>
Benchmark.prototype.setup = function() {
  var o = {};
  for (var i = 0; i < 1000; i++) {
    o['p' + i] = i;
  }

};
</script>

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Testing in CCBot 2.0.0 / Other 0.0.0
Test Ops/sec
delete object.property
 delete o.p;
pending…
delete object["property"]
for (var i = 0; i < 1000; i++) {
  delete o["p" + i];
}
pending…
object.property = false
 o.p = false;
pending…
object["property"] = false
for (var i = 0; i < 1000; i++) {
 o["p" + i] = false;
}
pending…
object.property = null
 o.p = null;
pending…
object.property = undefined
 o.p = undefined;
pending…
object["property"] = undefined
for (var i = 0; i < 1000; i++) {
  o["p" + i] = undefined;
}
pending…

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Revisions

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