"Type of undefined" vs "=== undefined" (v23)

Revision 23 of this benchmark created by hellraiser on

Setup

var a = 1, b = true, c = "c", d = [], e = {}, u;

Test runner

Ready to run.

Testing in
TestOps/sec
typeof undefined
typeof a === 'undefined';
typeof b === 'undefined';
typeof c === 'undefined';
typeof d === 'undefined';
typeof e === 'undefined';
ready
=== undefined
a === undefined;
b === undefined;
c === undefined;
d === undefined;
e === undefined;
 
ready
=== undefined(local)
a === u;
b === u;
c === u;
d === u;
e === u;
ready
void 0
a === void 0;
b === void 0;
c === void 0;
d === void 0;
e === void 0;
ready
triple cast
!!!a;
!!!b;
!!!c;
!!!d;
!!!e;
ready

Revisions

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