#15437: Internal error when applying a scoped type variable inside a typed expression quotation -------------------------------------+------------------------------------- Reporter: dminuoso | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.8.1 Component: Template Haskell | Version: 8.4.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: #13587, #15835 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by mpickering): I don't think types are really dealt with properly in typed template haskell. Your program is a lot like {{{ foo :: Int -> Q (TExp Int) foo x = [|| x ||] }}} In this case, we have to interpret the `x` as `$(lift x)` and we should do the same thing for types here. To go back to your program and some pseudo syntax: {{{ foo :: forall a. Q (TExp Int) foo = [|| get @$(lift a) ||] }}} We really mean something like this as the value of `a` is bound at compile-time but not at run-time so if we want to use it we have to use it in a splice. Does that sound sensible Simon? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15437#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler