Don't use an abstract base class; use roles...

{
  package IAmNotInYourIsa;
  use Moose::Role;
  requires 'dothis';
}

{
  package My::CGI;
  use Moose; with 'IAmNotInYourIsa';
  use CGI;
  sub dothis { ... my $q = CGI->new ... $q->param ... }
}

My::CGI->isa('IAmNotInYourIsa');    # false
My::CGI->does('IAmNotInYourIsa');   # true!

[download]

A good example can be seen in the Ask distribution on CPAN, where there are different implementations for STDIN/STDOUT, Tk, etc, each of which include:

with 'Ask::API';

[download]

Ask uses Moo rather than Moose, but the principle is the same.

perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

In reply to Re: Howto create a Moose baseclass/superclass/contract? Moose equivalent of Module::Pluggable? Favorite way to create base/super class? by tobyink
in thread Howto create a Moose baseclass/superclass/contract? Moose equivalent of Module::Pluggable? Favorite way to create base/super class? by Anonymous Monk

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