here the demo:

package Blubb;                                                        
+          

sub new {
  my $this = bless {};
#  $this->{circular} = $this;
}

sub DESTROY {
 warn "DESTROY\n";
}

package MAIN;
#{
   my $b = Blubb->new;
#}

END {
 warn "END\n";
}
[download]

DESTROY
END
[download]

What's surprising me is that it already works without curlies. I expected the variable to be accessible in END, like in BEGIN.

Hauke, I'm sure you want to try this out! ;-)

Remember, there's a lexical scope around the file, so

package Blubb;

...

package MAIN;
my $b = Blubb->new;

END {
  warn "END\n";
}
[download]

is the same as

{
  package Blubb;

  ...

  package MAIN;
  my $b = Blubb->new;

  END {
    warn "END\n";
  }
}
[download]

Since nothing captures $b, it ceases to exists as soon as the end of the lexical scope (the end of the file) is reached. If a sub were to capture $b, it would keep the variable alive until the sub was freed. This is usually during global destruction.

Hi Rolf,

The only chance I see is to have a second dummy variable which is guaranteed to be destroyed later and to put the code into it's destructor. Hauke, I'm sure you want to try this out! ;-)

Actually, I was thinking in a different direction: eliminating the circular references in the first place :-) See my node here.

Regards,
-- Hauke D

That wouldn't be sufficient, as demonstrated in Re^3: is there a way to ensure some code is the last thing that is run?.

> What's surprising me is that it already works without curlies. I expected the variable to be accessible in END, like in BEGIN.

Interesting Perl get's it right, when needed.

package Blubb;

sub new {
   my $this = bless {a=>42};
   #  $this->{circular} = $this;
}

sub DESTROY {
   warn "DESTROY\n";
}

package MAIN;

my $b = Blubb->new;




END {
   warn $b->{a};
   warn "END\n";
}
[download]

42 at c:/tmp/pm/destruct_end.pl line 20.
END
DESTROY
[download]

Cheers Rolf
_{(addicted to the Perl Programming Language and ☆☆☆☆ :)
Je suis Charlie!}