It's really unclear what you want to accomplish. It sounds like you want to subclass the root of an inheritance three and auto-generate the rest of the inheritance accordingly -- but then you're in a multiple inheritance situation, right? Do you mean @MyThingy::Handle::ISA = qw( MyThingy Thingy::Handle )?

I suppose this could be done just with @ISA munging, though it's ugly: 

[Original code deleted; see update below]

[download]

Update for japhy's update: Ah! Makes much more sense. How about something along these lines:

sub get_cog {
  my ($self) = @_;
  my $class = ref $self;

  if ( $class eq "Thingy" ) {
    return Thingy::Cog->new;
  }
  else {
    my $cog_class = "$class\::Cog";
    (my $cog_class_file = $cog_class . "pm") =~ s{::}{/};

    if ( grep { -e $_ } map { $_/$cog_class_file } @INC ) {
      require $cog_class_file;
      return $cog_class->new;
    }
    else {
      return Thingy::Cog->new;
    }
  }
}

[download]

-xdg

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In reply to Re: Inheritence in a Suite of Modules by xdg
in thread Inheritance in a Suite of Modules by japhy

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