Surprisinlgy little comment on this proposal. Perhaps it landed when yous were busy elsewhere. I'd like to push it to the committee soon; this is an invitation for more feedback.
Richard E wrote a nice brief summary https://github.com/ghc-proposals/ghc-proposals/pull/56#issuecomment-311421457 Thank you AntC ----- Original Message Follows ----- > After years of pondering this idea (in various forms), > and several rounds of discussion on several forums, > I've written it up. > > "This proposal tackles the thorny topic of Overlapping > instances, > for both type classes and Type Families/Associated types, > by annotating instance heads with type-level apartness > Guards. > Type-level disequality predicates appear in Sulzmann & > Stuckey 2002; > in the type-level ‘case selection’ in HList 2004; > and in various guises in Haskell cafe discussions in > following years. > This proposal builds on the apartness testing implemented > as part of the Closed Type Families work." > > All feedback welcome. > > https://github.com/AntC2/ghc-proposals/blob/instance-apartness-guards/proposals/0000-instance-apartness-guards.rst > > AntC _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/glasgow-haskell-users