#14610: newtype wrapping of a monadic stack kills performance -------------------------------------+------------------------------------- Reporter: mrkkrp | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.2.2 Resolution: | Keywords: JoinPoints Operating System: Unknown/Multiple | Architecture: Type of failure: Runtime | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: #14620 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by nomeata): That example is one where the result type depends on the parameters… but don’t see why we need that restriction – this code shows that it would be beneficial and not crash to allow it. The note `[The polymorphism rule of join points]` basically says “We need this restriction because the CPS translation would not be easily typable, but that is not very convincing. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14610#comment:15 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler