#13487: GHC panic with deferred custom type errors -------------------------------------+------------------------------------- Reporter: DimaSamoz | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.4.1 Component: GHCi | Version: 8.0.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple crash or panic | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by DimaSamoz): Thank you! Yes, that looks similar to my definition of `:-:`: {{{ #!haskell data Music :: forall n l. Partiture n l -> Type where -- | Parallel or harmonic composition of music. (:-:) :: ValidHarm m1 m2 => Music m1 -> Music m2 -> Music (m1 +-+ m2) ... }}} `ValidHarm` checks whether the two pieces of music can be composed and returns a `TypeError` if there is a composition mistake. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13487#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler