AUTOLOAD

[Ovid]

--- Dirk Koopman <djk at tobit.co.uk> wrote:

> > Of course it's possible. As already mentioned on this thread
> Class::Std 
> > implements a solution to the problem too. The point is that there's
> no 
> > *standard* way to percolate unhandled AUTOLOADs up the inheritance 
> > chain. If you allow for the possibility of multiple inheritance
> it's not 
> > entirely trivial to do either.
> 
> Er.. are you sure? AFAIK AUTOLOAD will simply use the *standard* 
> inheritance rules as documented in perloo et al.

It sort of does, but check this out:

--- Dirk Koopman <djk at tobit.co.uk> wrote:

> > Of course it's possible. As already mentioned on this thread
> Class::Std 
> > implements a solution to the problem too. The point is that there's
> no 
> > *standard* way to percolate unhandled AUTOLOADs up the inheritance 
> > chain. If you allow for the possibility of multiple inheritance
> it's not 
> > entirely trivial to do either.
> 
> Er.. are you sure? AFAIK AUTOLOAD will simply use the *standard* 
> inheritance rules as documented in perloo et al.

It sort of does, but check this out:

    #!/usr/bin/perl 

    use strict;
    use warnings;

    {
        package Parent;
        sub AUTOLOAD { print "In Parent\n" }

        package Child::A;
        our @ISA = 'Parent';

        sub AUTOLOAD {
            my $proto = shift;
            print "In Child::A\n";
            $proto->SUPER::AUTOLOAD();
        }

        package Child::B;
        our @ISA = 'Parent';

        sub AUTOLOAD {
            my $proto = shift;
            print "In Child::B\n";
            $proto->SUPER::AUTOLOAD();
        }

        package GrandChild;
        our @ISA = qw<Child::A Child::B>;

        sub AUTOLOAD {
            my $proto = shift;
            print "In GrandChild\n";
            $proto->SUPER::AUTOLOAD();
        }
    }

    GrandChild->whee;

You can never class the AUTOLOAD in Child::B.  That could very well be
undesired behavior.

Cheers,
Ovid

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