#9103: hackage's type-level-0.2.4 fails to compile -------------------------------------+------------------------------------- Reporter: slyfox | Owner: Type: bug | Status: closed Priority: normal | Milestone: Component: Compiler (Type | Version: 7.8.2 checker) | Keywords: Resolution: fixed | Architecture: Operating System: Unknown/Multiple | Unknown/Multiple Type of failure: GHC rejects | Test Case: valid program | Blocking: Blocked By: | Differential Revisions: Related Tickets: #8634 | -------------------------------------+------------------------------------- Changes (by jstolarek): * status: new => closed * resolution: => fixed Comment: Replying to [comment:13 simonpj]:
But as you'll see with `-fprint-explicit-kinds`, the coverage condition really is violated. I'm looking at the error message with `-fprint-explicit-kinds` and I don't see how the coverage condition is violated here :-/ {{{ Illegal instance declaration for ‘Add * k * (Succ k a) b (Succ k ab)’ The liberal coverage condition fails in class ‘Add’ for functional dependency: ‘a b -> ab’ Reason: lhs types ‘Succ k a’, ‘b’ do not jointly determine rhs type ‘Succ k ab’ In the instance declaration for ‘Add (Succ a) b (Succ ab)’ }}} But if you say this is correct then I trust your judgement. Closing this ticket.
-- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9103#comment:14 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler