Role Documentation

a while ago I found an article ( Roles: Composite Behavior Units of an Object ) describing the pros of using Roles and Interfaces or other ways from behavior requirements. Does any of you know where I can find more literature on this or learn more about roles?

I know this is almost a research topic, but maybe someone (maybe some Perl programmer) tried something with it (Moose?).

Note. The reason for adding the "perl" tag is because perhaps Perl programmers are more likely to provide an answer.