Re: inheritance turns back and bites

[borisz]

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);
}

[esskar]

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.

[borisz]

But SUPER is wrong here, I like to use SomeData or build something with __PACKAGE__.

[tovod-everett]

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);
}

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