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HyperZonk and Synapse0 have both suggested that the my is being ignored and all that is happenning is that $x is simply global.

It's a good theory, and certainly what I thought when I first looked at it. But it's easy to see that this isn't true: try comparing

sub foo{ my $x if 0; print "FOO: ", $x++, "\n"; } sub bar{ my $x if 0; print "BAR: ", $x--, "\n"; } foo, bar for (1..10);
with
sub foo{ print "FOO: ", $x++, "\n"; } sub bar{ print "BAR: ", $x--, "\n"; } foo, bar for (1..10);

I reckon the real reason is the explanation given by Abigail.

Now I don't think I would ever write my $x if 0 unless I wanted to get the sack for writing obscure code, but how about:

sub STATIC_VARIABLE{ 0 } sub foo{ STATIC_VARIABLE && my $x; print "FOO: ", $x++, "\n"; }
would that be difficult to understand? Would it carry on working in the future?

-- iakobski


In reply to Re: Re: Re: Unusual Closure Behaviour by iakobski
in thread Unusual Closure Behaviour by tachyon

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