gistfile1.txt

use strict;
use warnings;
use v5.20;

{
    package RoleA;

    use Moose::Role;

    requires 'foo';
}

{
    package RoleB;

    use Moose::Role;

    with 'RoleA';

    sub foo { 42 }
}


{
    package Class;

    use Moose;

    with 'RoleB';
}

say Class->new->foo;