Add custom xor implementation

[zilenCe]

Since JavaScript? lacks the xor operator it would be handy to have this function as a utility Function:

function $xor(a, b){
	return (a || b) && !(a && b);
}

Returns true if a OR b is true but not if both are
usage:

$xor(true, false) //returns true
$xor(true, true) //returns false
$xor(false, false) //returns false

[JanK]

!a != !b

[JanK]

oops, sorry forget my last comment

[ale]

It'd be more correct (and clear) like the boolean rules definitions:

function $xor	(a, b) {
		return ( (!a && b) || (a && !b) );
	}

[anonymous]

There are a few ways to do this that would make more sense than creating a new function. Javascript has a bitwise XOR operator and != essentially works as a XOR operator when dealing with booleans.

true ^ true = 0
true ^ false = 1
true != true = false
true != false = true

Now when you're not dealing with booleans, you just need to negate the expressions.

[mattcoz]

oops, wasn't logged in, that last comment was me

[JanK]

I don't think it's needed in MooTools, but here is a short version which converts the arguments to boolean before comparing them.

function $xor(a,b){return !a != !b;};
console.log($xor(0,0)); // false
console.log($xor(0,1)); // true
console.log($xor(1,0)); // true
console.log($xor(1,1)); // false

[tomocchino]

since it's such a simple function and seems to only be used in truly rare situations, im going to close this ticket. i don't think this needs to be part of the core