#! perl-slw
use strict;
use 5.010;
{
    package Roles::Jumper;
    ##requires "name";

    sub checkISA {
        no strict 'refs';
        my( $caller, $method ) = @_;
        return $caller if exists ${ "$caller\:\:" }{ $method };
        for my $parent ( @{ "$caller\:\:ISA" } ) {
            return $caller if exists ${ "$parent\:\:" }{ $method };
            return $_ while $_ = checkISA( $parent, $method );
        }
        return;
    }
    sub import {
        my $caller = caller;
        {
            no strict 'refs';
            die "'name' method required" unless exists ${ "$caller\:\:" }{name};
            die "'jump' already exists in package '$_'" while $_ = checkISA( $caller, 'jump' );
            *{ "$caller\:\:jump" } = \&jump;
        }
        return;
    }

    sub jump {
        my $self = shift;
        say $self->name, " jumps!";
    }

}
{
    package Jumper;
    sub jump { say 'How high?'; }
}
{
    package Pet::Dog;
##    our @ISA = qw[Jumper]; ## uncomment to test checkISA;

    ##use Role::Tiny::With;
    ##with "Roles::Jumper";
    #require Roles::Jumper; ## used if package in separate file
    Roles::Jumper->import;

    sub new {
        my $class = shift;
        bless {@_}, $class;
    }
##    sub jump { say 'How high?'; } ## uncomment to test checkISA
    sub name {
        my $self = shift;
        return $self->{name};
    }
    sub sound {
        my $self = shift;
        say $self->name, " says woof!";
    }
}

{
    package Pet::Cat;
    ##use Role::Tiny::With;
    ##with "Roles::Jumper";
    #require Roles::Jumper; ## used if package in separate file
    Roles::Jumper->import;

    sub new {
        my $class = shift;
        bless {@_}, $class;
    }
    sub name {
        my $self = shift;
        return $self->{name};
    }
    sub sound {
        my $self = shift;
        say $self->name, " says meow!";
    }
}

my $fido  = Pet::Dog->new(name => "Fido");
$fido->jump;
$fido->sound;

my $felix = Pet::Cat->new(name => "Felix");
$felix->jump;
$felix->sound;