Is it safe to use this kind of variable swapping in php ?
$a^=$b^=$a^=$b;
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1*(related)* [Reference - What does this symbol mean in PHP?](http://stackoverflow.com/questions/3737139/reference-what-does-this-symbol-mean-in-php) – Gordon Oct 16 '10 at 09:57
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Related: http://stackoverflow.com/questions/1998903/php-i-i-crashed-the-server – codaddict Oct 16 '10 at 09:58
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This sounds like a terrible idea. Imagine what this would do e.g. to objects or arrays – Pekka Oct 16 '10 at 10:23
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`$a = "cats"; $b = "fail whale";` – salathe Oct 16 '10 at 10:23
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No, because the variables may not be types that can be XORd the way you expect. The PHP idiom for swapping two variables (of any scalar type) in one line is:
list($a, $b) = array($b, $a);
Or simply:
[$a, $b] = [$b, $a];
moo.duwayne
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gregjor
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Yes it does... I wasn't sure list() worked with arrays but I tried it and it does work. – gregjor Oct 16 '10 at 10:47
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Only correct when both are integer. It's readability is poor,and efficiency is not good too,why use it?
matthewyang
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