in reply to Weird perl behavior regarding unloading class modules

Hmm, are you referring to the following behaviour: 
use strict;
use warnings;

package Foo;

our $Obj = Foo->new();

sub new {
  bless {}, shift;
}

sub DESTROY {
  my $this = shift;
  print "DESTROYING $this\n";
}  

sub END {
  print "Ending! (global = $Obj)\n";
}

## OUTPUTS

Ending! (global = Foo=HASH(0x1a7f0c8))
DESTROYING Foo=HASH(0x1a7f0c8)

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Odd indeed, that DESTOY would be called after END. These problems can usually be solved by explicitly undefing your instance object.

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(tye)Re2: Weird perl behavior regarding unloading class modules
by tye (Sage) on Jan 20, 2001 at 10:09 UTC

    Depends whether you want to be able to use your global objects from within your END block or not, eh? This was argued back and forth on p5p quite a bit, I think.

    I prefer to code like this: 

    #!/usr/bin/perl -w
use strict;
# use other modules here
# global variables here
exit(  main( @ARGV )  );
# subroutines here
sub main {
    my $object= Widget::->new();
    # more code here
    return 0;
}

    [download]
    so that I don't have an objects in global variables and I don't have to remember to undef things.

    A much worse problem, IMHO, is that once you get into the global destruction phase, objects are destroyed in some arbitrary order so that Z can be destroyed before X even if X holds a reference to Z. This means that X's destructor may find undef where it expects a reference to Z. This really sucks to me.

            - tye (but my friends call me "Tye")
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[d/l]
      exit(  main( @ARGV )  );
sub main {
  ...

      [download]
      That's a C-ish brogue if ever I've heard one :)
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