HI, Try this, Here it says that $x is not defined and therefore it creates a new local variable $x with 'my'.
Otherwise it uses the last value of x which is the default behaviour. 

sub foo {
        my $x if !defined $x;
        return ++$x;
}
for (1..7){ print foo(); };

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

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