Liz suggested `but`, but that creates a new entity with the role mixed in. Instead one can use `does` to mix in to an existing entity: role House {} r

Liz suggested `but`, but that creates a new entity with the role mixed in. Instead one can use `does` to mix in to an existing entity: role House {} role Boat {} my \id = 42; id does House; id does Boat; say id ~~ House; # True (What's missing is the ability to drop a mixin once it's been added via `does`.)