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Array vs Object Access (v3)

Revision 3 of this benchmark created on January 18, 2013

Description

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

Setup

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

Test runner

Ready to run.

Testing in
Test		Ops/sec
Array get/set	`a[0] + 1;`	ready
Object get/set	`b.p + 1;`	ready
	`b['p'] + 1;`	ready
	`c['0'] + 1;`	ready
	`d['fartmaster'] + 1;`	ready

Revisions

You can edit these tests or add more tests to this page by appending /edit to the URL.

Revision 1: published by Matt Marston on January 9, 2013
Revision 2: published on January 15, 2013
Revision 3: published on January 18, 2013
Revision 4: published on February 16, 2013
Revision 5: published on March 11, 2013
Revision 6: published by David on July 7, 2013
Revision 7: published on July 7, 2013
Revision 8: published on February 24, 2014
Revision 9: published on June 24, 2014
Revision 16: published by Matt C on January 5, 2015
Revision 21: published on January 31, 2016