The comma operator is twofold; in scalar context, it evaluates the left argument, then the right argument, and returns the right argument.

$x = (1 + 3, 5 + 7);  # $x gets 12
$y = (pop @r, 1000);  # @r gets pop()ed, $y gets 1000
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It has less precedence than =, so:

$a, $b = 1, 2;
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means

$a, ($b = 1), 2;
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In any other context, it just separates two expressions.

foo(), bar(), blat() if bonk();

@a = (1,1,2,3,5,8,13);
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_____________________________________________________
Jeff japhy Pinyan: Perl, regex, and perl hacker.
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