There are lots of cases where the BEGIN fixes problems. mod_perl is one. Several others boil down to variations on this problem: 

#!/usr/bin/perl -w
use strict;

print "Starts out false: ", boolToggle(), $/;
print "Then is true: ", boolToggle(), $/;
print "Then false: ", boolToggle(), $/;
print "Then true: ", boolToggle(), $/;

# BEGIN # Remove first "#" from this line to fix bug.
{
    my $static= 1;
    sub boolToggle {
        $static= $static ? 0 : 1;
        return $static;
    }
}

print "Then opposite of last time: ", boolToggle(), $/;

[download]
which produces: 
Starts out false: 1
Then is true: 0
Then false: 1
Then true: 0
Then opposite of last time: 0

[download]
Trying to topologically sort your subroutine declarations to avoid this problem is probably not a good solution.

        - tye (but my friends call me "Tye")

In reply to (tye)Re: A metaclosure? (use static vars) by tye
in thread A metaclosure? Howto? by PetaMem

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