#8851: Standalone deriving and GND behave differently --------------------------------------------+------------------------------ Reporter: simonpj | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (Type checker) | Version: 7.8.1-rc1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: None/Unknown | Unknown/Multiple Test Case: | Difficulty: Unknown Blocking: | Blocked By: | Related Tickets: --------------------------------------------+------------------------------ Comment (by simonpj): To me rejection (B) looks right. After all, is it safe to coerce between `(Monad Parser)` to `(Monad InnerIdrisParser)`? They might have very different instances. See Section 3.4 of the [http://research.microsoft.com/en- us/um/people/simonpj/papers/ext-f/ Safe Coercions paper]. Simon -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8851#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler