php parser error?

hi, i'm afraid i found (by chance :-) ) a parser error. look at this code:

<?
$ar1=array (1,2,3);
$ar2=array (4,5,6);

if(list($ar1_val)=each($ar1)&&list($ar2_val)=each($ar2))
	echo "Ok";
else
	echo "Error";

php simply hangs by parsing that (i tried it on both win and linux - last release, 4.0.4pl1).

the cure is to add more parenthesis, like this:

if((list($ar1_val)=each($ar1))&&(list($ar2_val)=each($ar2)))

but anyway, php should not hang in the first case...

i do not known any email for reporting potential bugs in php, so i sent it here.

bye

It's a buglette. it shouldn't hang though, so report that to www.php.net

now look at this:

if ($a=15 && $b=4)
{
};
echo $a;

You'd expect this to output 15 because $a=15 and $b=4

But this does not output 15, it outputs 1.
Why?

Because $b=4, and $a= (15 && $b) and that's 1.
That's why the parentheses solved it.

This seems kind of strange.
Would you like to explain a little more
why $a becomes 1 and not 15?

/Staffan

I think the answer is 1 because of right to left evaluation.

If we take $b=4, then $b becomes equal to 4, and evaluates as true.

$a becomes equal to 15 and true, which is true.

So,

$a = 1 (1 = true).

Ta da!

Magic!

I think.

Regards,

Richard Quadling.

Looks like it's right to left evaluation with the = and && operators having equal precedence.

Indeed, and that seems like a bug.

But it also kindof explains why the whole thing stops:
list() doesn't set a return code. 🙂