#9805: Use TrieMaps to speed up type class instance lookup -------------------------------------+------------------------------------- Reporter: ezyang | Owner: ezyang Type: task | Status: new Priority: normal | Milestone: Component: Compiler (Type | Version: 7.9 checker) | Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by ezyang): I picked this up again. I looked carefully at where the kind coercion is used. Specifically: * (TyVar case) When matching in `uVar`, it is used to get the two types to the same kind so that `eqType` may succeed. * (TyVar case) In `uUnrefined`, it is used to ensure that the `TvSubst` is well kinded * (CoercionTy case) It is used to extend the `CvSubst` So, although you don't say it explicitly, I think that I will need to pass `kco` around in the TrieMap implementation so that I can implement these methods correctly. One source of awkwardness here is that the TypeMap doesn't currently store `CastTy`, which means any coercions induced by them will be lost to the ether (I think what needs to be done is just to add back a map for CastTy constructor in TypeMap.) -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9805#comment:15 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler