Undefined vs Delete

JavaScript performance comparison

Revision 2 of this test case created

Info

Check which of setting to undefined or delete a variable is preferable.

Preparation code

 
<script>
Benchmark.prototype.teardown = function() {
    var testing = 123;
};
</script>

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Testing in unknown unknown
Test Ops/sec
Set to undefined
testing = undefined;
pending…
Delete variable
delete testing;
pending…
''
testing = ''
pending…
null
testing = null
pending…

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