
#13650: Implement KPush in types -------------------------------------+------------------------------------- Reporter: goldfire | Owner: (none) Type: task | Status: new Priority: high | Milestone: 8.4.1 Component: Compiler | Version: Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- A recent commit contributed a [https://phabricator.haskell.org/diffusion/GHC/browse/master/compiler/types/T... Note] that explains why we need the dreaded KPush rule to be implemented in `splitTyConApp`. Without KPush there, it's possible that we can have two types t1 and t2 such that {{{t1 `eqType` t2}}} and yet they respond differently to `splitTyConApp`: t1 = `(T |> co1) (a |> co2)` and t2 = `T a`. Both t1 and t2 are well-kinded and can have the same kind. But one is a `TyConApp` and one is an `AppTy`. (Actually, looking at this, perhaps the magic will be in `mkAppTy`, not `splitTyConApp`.) But I have to look closer. This ticket serves as a reminder to do so. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13650 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler