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Date: Sat, 30 Oct 2004 20:45:07 +0200
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Subject: operator strange behaviour
From: felho@avalon.aut.bme.hu (Hodicska Gergely)

Hi!

I tried to get answer on the general list, but I didn't get.
I have a little example, which generate strange output.

$a = 0;
$b = 1;
if ($a = 1 && $b = 0) {
     echo 'true ';
     var_dump($a);
     var_dump($b);
} else {
     echo 'false ';
     var_dump($a);
     var_dump($b);
}
Runing this we get: "flase bool(false) int(0)"

After the precedence table the first step should be evaluating the &&, 
and we get something like this: $a = false = 0, which should generate an 
error, while there isn't an "lvalue" on the left side of the =.
But doesn't this happen. It seems, that the evaluation of the first = 
came before evaluating the &&.

Can someone exactly explain how PHP process this condition?

THX in advance,
Felho