delete vs undefined vs null (v24)

Revision 24 of this benchmark created on

Description

The delete operator removes a property entirely. Setting a property to undefined removes the value. Setting a property to null changes the value to the null value.

Technically they are not equivalent, but in practice they are often used to mean the same thing: that a property is unset.

Setup

var o = {
       p: 1
    };

Test runner

Ready to run.

Testing in
TestOps/sec
delete object.property
o.x = 4;
 delete o.p;
ready
delete object["property"]
o.x = 4;
 delete o["p"];
ready
object.property = false
o.x = 4;
 o.p = false;
ready
object["property"] = false
o.x = 4;
 o["p"] = false;
ready
object.property = null
o.x = 4;
 o.p = null;
ready
object.property = undefined
o.x = 4;
 o.p = undefined;
ready

Revisions

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