RE: Re: How to call AUTOLOAD before @ISA?

But the thing is that I want to inherit all the methods from the superclass, but I only want to call them in a controlled fashion from AUTOLOAD when certain conditions are met. My idea was to do something like this:

sub AUTOLOAD {
  my $self=shift;
  my $method=$AUTOLOAD;
  $method=~s/^.*:://;
  if (certain conditions are met) {
    do something
  }
  else {
    $self->SUPER::$method(@_);
  }
}
[download]

The thing is that the check and the "do something" are all the same, but this applies to several methods, that's why I wanted to use AUTOLOAD.

I'm also pretty sure that this cannot be done (all the documentation seems to indicate so) and I have already solved my problem by dynamically defining the necessary subroutines in B's BEGIN block, but I will be glad to hear any other ideas.

Thanks,

--ZZamboni

Comment on RE: Re: How to call AUTOLOAD before @ISA? Download Code

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RE: RE: Re: How to call AUTOLOAD before @ISA? by chromatic (Archbishop) on May 10, 2000 at 18:33 UTC
There are a couple of other ways to get around this. If you're comfortable mucking about in the symbol table, you can generate your subroutines from a template (especially the "do some checks here" code) and eval() them into being the first time they're needed. I'd do that in a BEGIN block, perhaps. Another option is, of course, delegation -- probably the best approach. You could also fake inheritance, by not using @ISA, and hard-coding calls to the parent. That would allow you to use AUTOLOAD to generate them. You could even write a dispatcher method, to do all the checks for you, then find the appropriate subroutine. You'd have to pass the name of a method you want, and you could use a hash of sub refs to avoid symbolic references. That's not a bad solution. But there's no way I'm aware of to call AUTOLOAD before checking the inheritance tree. Code provided for any of these examples if you're really curious.	[reply]
RE: RE: Re: How to call AUTOLOAD before @ISA? by perlmonkey (Hermit) on May 10, 2000 at 05:45 UTC
well this is an obvious solution (okay maybe only obvious to my cloudy little mind): `sub AUTOLOAD { my $self=shift; my $method=$AUTOLOAD; my $PSEUDO_PARENT = 'A'; $method=~s/^.*:://; return if $method eq 'DESTROY'; if (certain conditions are met) { do something } else { #dynamically call the pseudo parent function my $return_value = eval("&{$PSEUDO_PARENT"."::"."$method}".'($s +elf, @_)'); #catch eval error! if( $@ ) { die $@; } #return whatever the eval'd function returned return $return_value; } }` [download] The problem with this is hardcoding the parent class in, instead of using SUPER. And with a combination of eval and AUTOLOAD you are sure to not the the optimal performance.	[reply] [d/l]