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POWhat should I do with an object that should no longer be used in Perl?
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copied!<p>I am writing a class that is linked to an external resource. One of the methods is a delete method that destroys the external resource. No further method calls should be made on that object. I was thinking of setting a flag and die'ing inside of all of the methods if the flag is set, but is there a better, easier way? Something involving DESTROY maybe?</p> <p>So far, I am really liking Axeman's suggestion, but using AUTOLOAD because I am too lazy to recreate all of the methods:</p> <pre><code>#!/usr/bin/perl use strict; use warnings; my $er = ExternalResource->new; $er->meth1; $er->meth2; $er->delete; $er->meth1; $er->meth2; $er->undelete; $er->meth1; $er->meth2; $er->delete; $er->meth1; $er->meth2; $er->meth3; package ExternalResource; use strict; use warnings; sub new { my $class = shift; return bless {}, $class; } sub meth1 { my $self = shift; print "in meth1\n"; } sub meth2 { my $self = shift; print "in meth2\n"; } sub delete { my $self = shift; $self->{orig_class} = ref $self; return bless $self, "ExternalResource::Dead"; } package ExternalResource::Dead; use strict; use Carp; our $AUTOLOAD; BEGIN { our %methods = map { $_ => 1 } qw/meth1 meth2 delete new/; } our %methods; sub undelete { my $self = shift; #do whatever needs to be done to undelete resource return bless $self, $self->{orig_class}; } sub AUTOLOAD { my $meth = (split /::/, $AUTOLOAD)[-1]; croak "$meth is not a method for this object" unless $methods{$meth}; carp "can't call $meth on object because it has been deleted"; return 0; } </code></pre>

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