is there a XNOR operator in javascript

Question

I'm new to js and I wonder if there is a XNOR operator in JS. I tried !(a^b) but it gives weird result. For example:

var a,b="aa"; 
a^b

this code returns true, however, I XNOR returns false.
UPDATE
I need to return true if the two operand are true(different from false values), or the two are false (both equals to : null, undefined,""-empty string- or 0)

Have you considered using xor and not in chain? Also what is this `var a,b="aa"; a^b`? It looks completely wrong and doesn't give true at all. — ASDFGerte, Jun 07 '18 at 13:27
[Same question in C#](https://stackoverflow.com/questions/7054124/is-there-xnor-logical-biconditional-operator-in-c) - hesitant to close as a dupe (hence why I undid my dupehammer vote) due to it being a different language. — James Thorpe, Jun 07 '18 at 13:29
Why are you trying to compare a string and an undefined value with bitwise operators?! — Bergi, Jun 07 '18 at 13:50

Brandon Dixon · Accepted Answer · 2018-06-07T13:55:01.350

25

Above is the truth table for XNOR. If A and B are both FALSE or TRUE, the resulting XNOR is true. Therefore, it seems to me as if simply checking for equality is actually the equivalent of XNOR.

So:

(a === b) = (a XNOR b)

EDIT: to work properly with your conditions: this should work:

a == b

Note that there are two "=", not three, indicating that this is comparing "truthy" values.

edited Jun 07 '18 at 13:55

answered Jun 07 '18 at 13:32

Brandon Dixon

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@aName Then use `!a === !b` if you need to cast your values to proper booleans first – Bergi Jun 07 '18 at 13:51
I've updated my answer, try this: a == b (note that there are only two equal signs, not three). – Brandon Dixon Jun 07 '18 at 13:55
that's it @Bergi – aName Jun 07 '18 at 14:11

score 17 · Answer 2 · answered Jun 07 '18 at 13:43

17

The bitwise xnor is:

~(a ^ b)

And the logical one;

a === b

answered Jun 07 '18 at 13:43

Jonas Wilms

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score 0 · Answer 3 · answered Jan 24 '19 at 23:25

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try (a^b)==0 i think result of XNOR in javascript is: true^true = 0

answered Jan 24 '19 at 23:25

Hossein Aghatabar

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score -1 · Answer 4 · answered Jun 07 '18 at 13:30

-1

try this (!(A ^ B)) or this (A && B) || (!A && !B)

answered Jun 07 '18 at 13:30

shmnff

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Bitwise not is `~` – ASDFGerte Jun 07 '18 at 13:32
yeah that what I'm using now, but I wonder if there is an operator that makes it simpler – aName Jun 07 '18 at 13:38

is there a XNOR operator in javascript

4 Answers4