One way to swap two variables with no temporaries that isn't specific to perl is:

$a = $a ^ $b;
$b = $a ^ $b;
$a = $a ^ $b;

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Update: The '^' operator is called "exclusive or" or XOR. It returns the bitwise XOR of the operands. XOR is equivalent to bitwise addition mod 2.

In reply to Re: Exchanging Variables by dailylemma
in thread Exchanging Variables by Mr.T

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