#12033: [TypeApplications] GHC internal error -------------------------------------+------------------------------------- Reporter: Iceland_jack | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.1 Keywords: | Operating System: Unknown/Multiple TypeApplications | Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Toying around, got {{{ GHCi, version 8.1.20160503: http://www.haskell.org/ghc/ :? for help [1 of 1] Compiling Main ( /tmp/CatFail.hs, interpreted ) /tmp/CatFail.hs:55:26: error: • GHC internal error: ‘a’ is not in scope during type checking, but it passed the renamer tcl_env of environment: [a1Ej :-> Type variable ‘i’ = i, a1Ek :-> Type variable ‘p’ = p, a1Et :-> Type variable ‘a’ = a, a1Eu :-> Type variable ‘b’ = b] • In the first argument of ‘Vacuous’, namely ‘a’ In the type ‘Vacuous a’ In the expression: Dict @(Vacuous a) /tmp/CatFail.hs:66:10: error: • Couldn't match type ‘Fun p q’ with ‘Vacuous’ arising from a use of ‘Main.$dmsrc’ • In the expression: Main.$dmsrc In an equation for ‘src’: src = Main.$dmsrc In the instance declaration for ‘Category (Nat p q)’ • Relevant bindings include src :: Nat p q a b -> Dict (Ob (Nat p q) a) (bound at /tmp/CatFail.hs:66:10) Failed, modules loaded: none. }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12033 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler