The only supported way to get that information is to use Moose's meta model, which will also work against Moo classes. Poking into Moo's internals is unsupported and could break at any time.

A better question is why you are looking for this information in the first place. It seems like a case where you are trying to answer the wrong question.

Not sure I understand what you mean by "what the requires are" ... or by "a list of methods that are required in order to compose a role".

Do you mean the attributes of the class that are required to be populated when you instantiate it, ie required arguments?

Under Role::Tiny there is a
requires qw(foo bar);
Described as "Declares a list of methods that must be defined to compose role."
I am looking for a way to introspect a role from the outside to determine if any requires has been declared and what specific methods were declared in the requires. In this case foo and bar.

There's no official way to do that, but if you can live with an undocumented approach, you can inspect $Role::Tiny::INFO{YourRole}{requires} e.g.

package BasicRole;

use Moo::Role;

requires qw(abra cadabra);

1;

package App;
use Moo;
with 'BasicRole';

sub abra { 'abra' }

sub cadabra { 'cadabra' }

1;

package main;
use strict;
use Data::Dump 'dd';

my $app = App->new();
dd $Role::Tiny::INFO{BasicRole}{requires};

__END__

Output:
["abra", "cadabra"]
[download]

I think you'll need Moose::Meta::Role or something equally Moosey to do that.

Maybe this will help: http://search.cpan.org/dist/Moose/lib/Moose/Meta/Role.pm#$metarole->get_required_method_list



The way forward always starts with a minimal test.