#10751: Implement Phase 1 of MonadFail Proposal (MFP) -------------------------------------+------------------------------------- Reporter: hvr | Owner: quchen Type: task | Status: patch Priority: highest | Milestone: 8.0.1 Component: Compiler | Version: 7.10.2 Resolution: | Keywords: report-impact Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1248 -------------------------------------+------------------------------------- Comment (by spl): I worked a bit on the wiki proposal. I think it would be good to indicate (1) which {{{MonadFail}}} instances will be created and (2) which types with {{{Monad}}} instances will not have {{{MonadFail}}} instances. Since this change affects a number of important packages, those packages should probably be included. Also, I'm not clear on the conclusion for having {{{Monad}}} vs. {{{Applicative}}} as the superclass constraint on {{{MonadFail}}}. I tried to develop the discussion text on this a bit. Since we're getting {{{ApplicativeDo}}} soon, I think it would be useful to work out whether and how these two features are related. I didn't see anything on ApplicativeDo referring to the desugaring of pattern matching. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10751#comment:16 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler