It's been a while since I hit the keys on my codeboard - so apologies if ya'all know all this anyway.

I've recently discovered Object::Pad - and love it. Fingers crossed for some future OO goodness in CORe.

I've kind of forgotten where to ask Perl questions, and posted one on Discord->#perl:

A question on Object::Pad and virtual parent classes.

I want to class Parent :does(RoleA) :does(RoleB) and have class ChildA isa:(Parent); class ChildB isa:(Parent) etc. without having to implement the RoleA and RoleB requires methods inside Parent - in other words, Parent is a virtual class - one that would never be instantiated.

If I do this, it appears that the :does() are evaluated on Parent at compilation rather than instantiation of ChildA or ChildB which actually do implement the requires.

Is there a way to do virtual parent classes?

Kudos to gordonfish for suggesting using role to do this.

So as illustration, you can use role as follows to compose virtual classes. 

    #!/usr/bin/perl
    #-----------------------------------------------------------------
+-------------
    use v5.32;
    use Object::Pad;

    role Role::FeederThings {
      requires earnDosh;
      requires buyKFC;
    }

    role Role::TaxiDriver {
      requires waitForever;
      requires driveForMiles;
    }

    role Role::DadThings
      :does(Role::FeederThings)
      :does(Role::TaxiDriver) {
    }

    class Parent
      :does(Role::DadThings) {

    }

[download]

Which results in: 

  Class Parent does not provide a required method named 'earnDosh' at 
+./,t1.pl line 25.

[download]

Just sharing...

0.02$AU, Jeff.

In reply to Object::Pad - Virtual Classes can be composed using Roles. by jaa

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