What is the purpose of your bar package? If you wanted to reuse methods from package foo without refactoring foo itself, you could use method forwarding:

package bar;
use Moo::Role;

has 'foo' => (
    is => 'rwp',
    handles => [qw/foo/], # put other methods to be delegated here
);
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Then any class that consumes this role will be able to call the methods of foo that you set up delegation for.

If you were wanting to split up the methods into different roles, you could e.g. move the foo() method to its own role:

package Foo::Role;
sub foo {
    print "foo\n";
}
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Then if bar wanted to 'extend' this with other methods:

package bar;
use Moo::Role;
with 'Foo::Role';

# ... other methods
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