#15871: Revamp -fprint-explicit-kinds -------------------------------------+------------------------------------- Reporter: goldfire | Owner: (none) Type: task | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.6.2 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- With the imminent #12045, we will have type application in kinds. This ticket tracks mirroring this new behavior in the pretty-printer. To wit, when `-fprint-explicit-kinds` is enabled, we should 1. Print instantiations of specified variables like `@...`. 2. Print instantiations of inferred variables like `@{...}`. Examples: {{{#!hs data Proxy (a :: k) = Proxy -- Then, `Proxy Int` would be printed as `Proxy @Type Int` with -fprint- explicit-kinds data Proxy2 a = Proxy2 -- Then, `Proxy2 Int` would be printed as `Proxy2 @{Type} Int` with -fprint-explicit-kinds }}} In addition, sometimes error messages suggest enabling `-fprint-explicit- kinds`. Instead of doing this, we should just locally enable the flag. The existence of the `@` prefixes will alert the reader that these are not type arguments. (Without the `@` syntax, locally and silently enabling `-fprint-explicit-kinds` would be very confusing.) -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15871 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler