Well, it depends. If you are using roles, there are a couple of ways of resolving conflicts, but basically it works out as:
However, if you prefer, you can have your cake and eat it too.
And that's nice because theoretically, if your elf knows various professions, she should know how the activities with those professions vary, just as one person might know how to drive a race car but wouldn't think of doing that with a dump truck, even though both activies are driving.
Unfortunately, when it comes to your specific example with mixins, I'm a little less clear about disambiguation. When you use a role at runtime on an instance, you get new anonymous classes that are related to the instance via inheritance. Thus, the following has the inheritance ordering problem again:$elf does Thief does Sentry;
In that example, $elf.hide calls Sentry.hide as Thief.hide is further up the inheritance tree. This seems to limit the utility of mixins, but I can't be sure. Further clarification would be nice.
In reply to Re^2: Solving compositional problems with Perl 6 roles