Re: [GHC] #14515: "Same" higher-rank kind synonyms behave differently

15 Dec 2017


      #14515: "Same" higher-rank kind synonyms behave differently
-------------------------------------+-------------------------------------
        Reporter:  Iceland_jack      |                Owner:  (none)
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.2.1
  checker)                           |
      Resolution:  fixed             |             Keywords:  TypeInType
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  GHC rejects       |            Test Case:
  valid program                      |  polykinds/T14515
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Changes (by simonpj):

 * status:  new => closed
 * testcase:   => polykinds/T14515
 * resolution:   => fixed


Comment:

 Great examples!  Fixed by
 {{{
 commit 68149452a793aedd8d468b689dc93fb2ba5ec436
 Author: Simon Peyton Jones 
 Date:   Fri Dec 15 09:29:12 2017 +0000

     Fix tcDataKindSig

     This patch fixes an outright bug in tcDataKindSig, shown up in Trac
     of a data type declaration.  See Note [TyConBinders for the result
 kind
     signature of a data type]

     I also took the opportunity to elminate the DataKindCheck argument
     and data type from tcDataKindSig, instead moving the check to the
     call site, which is easier to understand.
...
---------------------------------------------------------------
68149452a793aedd8d468b689dc93fb2ba5ec436
  compiler/typecheck/TcHsType.hs             | 126
 +++++++++++++++++------------
  compiler/typecheck/TcInstDcls.hs           |  20 ++---
  compiler/typecheck/TcTyClsDecls.hs         |  22 +++--
  compiler/types/Type.hs                     |  16 +---
  testsuite/tests/ghci/scripts/T13407.stdout |   2 +-
  testsuite/tests/polykinds/T14515.hs        |  13 +++
  testsuite/tests/polykinds/all.T            |   1 +
  7 files changed, 116 insertions(+), 84 deletions(-)

 }}}

-- 
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14515#comment:3
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