2x getElementById vs assigning var

JavaScript performance comparison

Test case created

Preparation code

<div id="a" class="b">
  <div id="aa" class="bb">
  </div>
</div>
<script>
Benchmark.prototype.setup = function() {
    var t;
};
</script>

Preparation code output

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Testing in unknown unknown
Test Ops/sec
2x getElementById
if (document.getElementById('a')) t = document.getElementById('a');
t = null;
pending…
temp = getElementById
var temp = document.getElementById('a')
if (temp) t = temp;
t = null;
pending…

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