How does the bitwise operator XOR ('^') work?

Question

I\'m a little confused when I see the output of following code:

$x = \"a\";
$y = \"b\";
$x ^= $y;
$y ^= $x;
$x ^= $y;
echo $x; //Got b
echo $y; //Got a
         


        

Answer 1

In this example, when you're using ^ characters, they are casted to integers. So

"a" ^ "b"

is the same as:

ord("a") ^ ord ("b")

with one exception. In the first example, the result was casted back to a string. For example:

"a" ^ "6" == "W"

because of:

ord("a") ^ ord("6") == 87

and

chr(87) == "W"