Array vs Object Access

JavaScript performance comparison

Test case created by Matt Marston

Info

JavaScript arrays are basically just objects with integer property names. Is there any performance difference when accessing an array vs an object?

Preparation code

 
<script>
Benchmark.prototype.setup = function() {
    var a = [0], b = { "0":0 };
};
</script>

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Testing in unknown unknown
Test Ops/sec
Array get/set
a[0] = a[0] + 1;
pending…
Object get/set
a["0"] = a["0"] + 1;
pending…

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