We need to add role annotations for 7.8

[Andres Löh]

Hi there.

Please forgive my ignorance w.r.t. roles, but why aren't all of these
representational?

> Map k v -- k: nominal, v: represententional
> Set a -- k: nominal

AFAIK both Map and Set are "normal" datatypes. Not GADTs, no type
families involved. Why would anything need to be "nominal" then?

Thanks in advance for explaining.

Cheers,
  Andres

-- 
Andres Löh, Haskell Consultant
Well-Typed LLP, http://www.well-typed.com