Array vs Object Access

JavaScript performance comparison

Revision 5 of this test case created


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

Preparation code

Benchmark.prototype.setup = function() {
    var a=[0,1], b={x:0,y:1};

Test runner

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Testing in unknown unknown
Test Ops/sec
Array get/set
a = [0,1];
a[0] = a[1] + 1;
Object get/set
b = {x:0,y:1};
b.x = b.y + 1;

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