My Win32 Perl/Tk code looks a bit like this: 

use warnings;
my $Timer;
my $Display;  # This is the Canvas where the widgets are drawn

{main code skipped over}

sub showProblem {
$Timer = $Display->after(shift,
      sub {
          $Globalvariable = blah blah blah...
          $Timer->cancel();
      });
}

[download]

I get a warning
Variable "$Globalvariable" may be unavailable at some line number...

It seems that putting the global in an anonymous sub is a problem here, although warning aside, the code works perfectly. Yet I have other cases (with the same variable) where Warnings does not complain. Further, if there are two references to $Globalvariable in the anonymous sub, the second one does not generate a warning.

Any clue as to why this might be? I can eliminate the message by the use of "no warnings" in the anonymous sub, but I'm still confused by why I would need to do this. What is the Warnings pragma trying to tell me that I am too stupid to see?

Please educate me...

Nat

In reply to Help with 'use Warnings' please? by wa4otj

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