Re: [core libraries] Data.Display - Textual representation of Haskell values (was Re: PROPOSAL: Add displayException to Exception typeclass)

* I think usage of MINIMAL pragmas could help a lot for your concerns about which of `display` or `displayBuilder` the user implements.

I'm not sure this will work. We would need to specify something like {} | {displayBuilder} as minimal complete definition (where {} denotes the empty set), but I'm not aware of a way to specify the empty set with MINIMAL. Unless somebody knows a solution, I would probably open a GHC ticket and propose to extend the MINIMAL pragma to allow for empty sets. Cheers, Simon