That is, the error message indicates only that $obj is undef, not that the object to which $obj formerly pointed has been destroyed.

First, a variable has no memory of what it was. It just knows what it is.

Secondly, I'm baffled by your explanation of the example's output. It seems clear to me that the output from the DESTROY method comes before the error message, yet you conclude that DESTROY isn't called until after the error message.

I have to admit I have no idea what the example is supposed to demonstrate with all the eval()'s, strange names, and unintelligible (English?) output. Here is my example (which seems to prove your conclusion):

use strict;
use warnings;
use 5.010;

$| = 1;

{
    package Dog;

    sub new { return bless {}; }
    sub bark { say 'Bow wow!' }
    sub DESTROY { print "destroy\n"; }
}

my $dog = Dog->new();

print 'hello', 
      $dog->bark(), 
      undef $dog, 
      $dog->bark(), 
      'world',
;

--output:--
Bow wow!
Can't call method "bark" on an undefined value at 2.pl line 17.
destroy

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In reply to Re^2: when is destroy function called by 7stud
in thread when is destroy function called by david2008

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