Hi,
I have a problem in a .pm file that defines a single sub containing several closures that use variables of the main sub. I tried following and it worked fine as a .pm sub used in another .pl file. 
sub out {
    my $x = shift;
    local *in = sub {
        my ($inn) = @_;
        $x += $inn;
        return $x;  
    };
    local *in_2 = sub { 
        my $arg = 1;
        my $rs = in($arg);
        return $x * 10 + $rs;
    };
    return $x + in_2();
}

[download]
But in my real package I get a failure because of an undefined sub if I localize anonymous subs. If I write them like bellow and ignore the warning because of "variable will not stay shared" I do not get the failure. Why, what does cause a sub to be undefined? I use Math::RungeKutta. Does it have any problems with that kind of closures? 
sub upper {

$var;

runge::kutta things happen with help of dydt

sub help {
do something using $var from sub upper
}

sub dydt {
return help(blah);
}

}

[download]
Thank you very much.

In reply to Closures and undefined subs by Anonymous Monk

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