Array vs Object Access

JavaScript performance comparison

Revision 4 of this test case created

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() {
    window.confirm = function(){};
    var a = [0], b = { "p":0 }, c = {"0":0}, d = {"fartmaster":0};
};
</script>

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Testing in unknown unknown
Test Ops/sec
Array get/set
a[0] + 1;
pending…
Object get/set
b.p + 1;
pending…
b['p'] + 1;
pending…
c['0'] + 1;
pending…
d['fart-mas1ter'] + 1;
pending…

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