#10321: GHC.TypeLits.Nat types no longer fully simplified. -------------------------------------+------------------------------------- Reporter: darchon | Owner: Type: bug | Status: infoneeded Priority: normal | Milestone: 7.10.2 Component: Compiler (Type | Version: 7.10.1 checker) | Keywords: TypeLits Resolution: | Architecture: Operating System: Unknown/Multiple | Unknown/Multiple Type of failure: Other | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Revisions: -------------------------------------+------------------------------------- Comment (by goldfire): But yet we take (significant) pains not to look through type synonyms when reporting errors... we even avoid looking through type synonyms when normalizing! So, is the general idea that vanilla type synonyms are preferred over their RHSs, but reducing type families is better than leaving them unreduced? Perhaps. I have no objection to this. It is a little odd that changing a vanilla type synonym to a closed type family with one (universal) equation would change behavior, but this is all pretty- printing and heuristic anyway, so that's not too bad. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10321#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler