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undef-or-typeof-undef

Benchmark created by rmunson on August 31, 2015

Description

If a variable is guaranteed to exist, though may have a value of undefined... which test is faster?

Preparation HTML

<script>
var STR_UNDEFINED="undefined",
    UNDEFINED;
</script>

Setup

var defined="thing",
        notdefined;

Test runner

Ready to run.

Testing in
Test		Ops/sec
typeof undefined	`(typeof defined === STR_UNDEFINED); (typeof notdefined === STR_UNDEFINED);`	ready
undef equals	`(defined === UNDEFINED); (notdefined === UNDEFINED);`	ready

Revisions

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

Revision 1: published by rmunson on August 31, 2015