in reply to inheritance turns back and bites

you expect that increment call SomeData::add, but it calls MyNumber::add. Because it is a MyNumber object. If you do not want that, write in package SomeData 
sub increment {
    my $self = shift;
    $self->SomeData::add(number => 1);
}

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Boris

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Re: Re: inheritance turns back and bites
by esskar (Deacon) on Mar 01, 2004 at 13:46 UTC
    Always use SUPER instead of the parent-class-name; so in the case of changeing the parent-class, you won't have to replace all the "SomeData::" stuff to the new parent-class-name.
    SUPER is pretty super.
[reply]
      But SUPER is wrong here, I like to use SomeData or build something with __PACKAGE__.
      Boris
[reply]
        If your intent is to ensure that increment calls add in the same package, why not use: 
        sub increment {
    my $self = shift;
    &add($self, number => 1);
}

        [download]
        Use subroutine calls when you want to create your own explicit binding, use -> notation when you desire runtime binding of the message.

        Of course, it would be my opinion that it is particularly bad form for a child class to re-implement a method in a manner that is not backward compatible - it's a violation of the contract as far as I'm concerned.

        --Toby Ovod-Everett

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