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.
s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;

In reply to Re: The Comma Operator by japhy
in thread The Comma Operator by dsb

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