#11594: closed empty type families fully applied get reduced lazily when in a constraint tuple and fully applied -------------------------------------+------------------------------------- Reporter: carter | Owner: Type: feature request | Status: new Priority: normal | Milestone: 8.0.1 Component: Compiler (Type | Version: 7.10.2 checker) | Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by goldfire): * type: bug => feature request Comment: To paraphrase, you want GHC to recognize that an empty closed type family is insoluble. Although this is a decent suggestion, would a use of `TypeError` work for you? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11594#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler