Re: [GHC] #7778: kindFunResult panic with => inside a constraint

30 Apr 2013

      #7778: kindFunResult panic with => inside a constraint
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    Reporter:  monoidal                 |       Owner:  simonpj         
        Type:  bug                      |      Status:  new             
    Priority:  normal                   |   Milestone:  7.8.1           
   Component:  Compiler (Type checker)  |     Version:  7.6.2           
    Keywords:                           |          Os:  Unknown/Multiple
Architecture:  Unknown/Multiple         |     Failure:  None/Unknown    
  Difficulty:  Unknown                  |    Testcase:                  
   Blockedby:                           |    Blocking:                  
     Related:                           |  
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Comment(by simonpj@…):

 commit d3149f6096a987e94d4989e537c1a133bcbb9a6f
 {{{
 Author: Simon Peyton Jones 
 Date:   Mon Apr 29 17:26:17 2013 +0100

     Tighten up on the kind checking for foralls

     In particular,
        (forall a. Num a => ...)
     always has kind *, becuase the "=>" really is a function.

     It turned out that this was at the bottom of the crash in Trac #7778,
     which is now fixed

  compiler/typecheck/TcHsType.lhs   |   31 ++++++++++++++++++++++++-------
  compiler/typecheck/TcValidity.lhs |   16 +++++++++-------
  2 files changed, 33 insertions(+), 14 deletions(-)
 }}}

-- 
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7778#comment:3
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