#15264: Warn about implicit kind variables with -Wcompat -------------------------------------+------------------------------------- Reporter: int-index | Owner: (none) Type: task | Status: new Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.5 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Poor/confusing | Unknown/Multiple error message | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by int-index): * priority: high => normal Old description:

According to an accepted proposal https://github.com/ghc-proposals/ghc- proposals/blob/master/proposals/0024-no-kind-vars.rst:

With `-Wcompat`, warn if a kind variable is brought into scope implicitly in a type with an explicit `forall`. This applies to type signatures and to other contexts that allow a `forall` with the forall- or-nothing rule in effect (for example, class instances).

Creating ticket just for the record. Implementation coming soon. Setting priority as high because if the warning doesn't make it into the release, the actual change will have to be delayed by another half a year.

New description: According to an accepted proposal https://github.com/ghc-proposals/ghc- proposals/blob/master/proposals/0024-no-kind-vars.rst: With `-Wcompat`, warn if a kind variable is brought into scope implicitly in a type with an explicit `forall`. This applies to type signatures and to other contexts that allow a `forall` with the forall-or- nothing rule in effect (for example, class instances). Creating ticket just for the record. Implementation coming soon. -- -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15264#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#15264: Warn about implicit kind variables with -Wcompat -------------------------------------+------------------------------------- Reporter: int-index | Owner: (none) Type: task | Status: patch Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.5 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Poor/confusing | Unknown/Multiple error message | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D4834 Wiki Page: | -------------------------------------+------------------------------------- Comment (by Ben Gamari ): In [changeset:"8df24474d0194d28b8273c1539af05793156e23f/ghc" 8df24474/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="8df24474d0194d28b8273c1539af05793156e23f" Warn about implicit kind variables with -Wcompat According to an accepted proposal https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/002 4-no-kind-vars.rst With -Wcompat, warn if a kind variable is brought into scope implicitly in a type with an explicit forall. This applies to type signatures and to other contexts that allow a forall with the forall-or-nothing rule in effect (for example, class instances). Test Plan: Validate Reviewers: goldfire, hvr, bgamari, RyanGlScott Reviewed By: goldfire Subscribers: RyanGlScott, rwbarton, thomie, carter GHC Trac Issues: #15264 Differential Revision: https://phabricator.haskell.org/D4834 }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15264#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#15264: Warn about implicit kind variables with -Wcompat -------------------------------------+------------------------------------- Reporter: int-index | Owner: (none) Type: task | Status: closed Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.5 Resolution: fixed | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: Poor/confusing | Test Case: error message | dependent/should_compile/T15264 Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D4834 Wiki Page: | -------------------------------------+------------------------------------- Changes (by simonpj): * testcase: => dependent/should_compile/T15264 -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15264#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler