Re: [GHC] #14579: GeneralizedNewtypeDeriving produces ambiguously-kinded code

5 Jan 2019

      #14579: GeneralizedNewtypeDeriving produces ambiguously-kinded code
-------------------------------------+-------------------------------------
        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.10.1
       Component:  Compiler (Type    |              Version:  8.2.2
  checker)                           |
      Resolution:                    |             Keywords:  deriving
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  GHC rejects       |            Test Case:
  valid program                      |  deriving/should_compile/T14579{a}
      Blocked By:  12045             |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D4264,
       Wiki Page:                    |  Phab:D5229
-------------------------------------+-------------------------------------
Changes (by RyanGlScott):

 * testcase:  deriving/should_compile/T14579 =>
     deriving/should_compile/T14579{a}
 * differential:  Phab:D4264 => Phab:D4264, Phab:D5229

Comment:

 A test case was added in
 [https://gitlab.haskell.org/ghc/ghc/commit/17bd163566153babbf51adaff8397f948a...
 17bd163566153babbf51adaff8397f948ae363ca]:

 {{{
 Author: mynguyen 
 Date:   Tue Dec 18 11:52:26 2018 -0500

     Visible kind application

     Summary:
     This patch implements visible kind application (GHC Proposal
 15/#12045), as well as #15360 and #15362.
     It also refactors unnamed wildcard handling, and requires that type
 equations in type families in Template Haskell be
     written with full type on lhs. PartialTypeSignatures are on and
 warnings are off automatically with visible kind
     application, just like in term-level.

     There are a few remaining issues with this patch, as documented in
     ticket #16082.

     Includes a submodule update for Haddock.

     Test Plan: Tests T12045a/b/c/TH1/TH2, T15362, T15592a

     Reviewers: simonpj, goldfire, bgamari, alanz, RyanGlScott,
 Iceland_jack

     Subscribers: ningning, Iceland_jack, RyanGlScott, int-index, rwbarton,
 mpickering, carter

     GHC Trac Issues: `#12045`, `#15362`, `#15592`, `#15788`, `#15793`,
 `#15795`, `#15797`, `#15799`, `#15801`, `#15807`, `#15816`

     Differential Revision: https://phabricator.haskell.org/D5229
 }}}

 To ensure that the code in comment:12 actually typechecks. However, the
 task of making `GeneralizedNewtypeDeriving` actually generate this code
 remains to be done.

-- 
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14579#comment:19
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