| Is there any reason to prefer such “slightly wrong” definitions which | are overwritten with built-in stuff over simply putting the type | constructors and functions into GHC.Prim?
Because we must generate executable machine instructions for mkCast, and a real info-table for the NT data constructor. GHC.Prim, by contrast, has no associated code whatsoever. | > * We are only going to allow GHC-derived instances of NT. | | Just to be sure: Preventing manual instances is currently not possible | and such a feature would have to be added to GHC, right? Well Typable is close. We are trying to prevent user-defined instances of that. But generally yes it's a new feature. Simon _______________________________________________ ghc-devs mailing list ghc-devs@haskell.org http://www.haskell.org/mailman/listinfo/ghc-devs