Re: [GHC] #7875: Unhelpful IncoherentInstances suggestion with FunctionalDependencies

3 May 2013

      #7875: Unhelpful IncoherentInstances suggestion with FunctionalDependencies
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Reporter:  dreixel           |          Owner:                  
    Type:  bug               |         Status:  new             
Priority:  normal            |      Component:  Compiler        
 Version:  7.7               |       Keywords:                  
      Os:  Unknown/Multiple  |   Architecture:  Unknown/Multiple
 Failure:  None/Unknown      |      Blockedby:                  
Blocking:                    |        Related:                  
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Comment(by simonpj@…):

 commit d31dd88d4eae4e199d1341da2e7a7550a5e4c3a2
 {{{
 Author: Simon Peyton Jones 
 Date:   Fri May 3 07:42:57 2013 +0100

     In doTopReactDict, try lookup even if fundeps work

     Previously we looked for fundeps, and if any fired we
     didn't try to solve the constraint.  But that's wrong
     (see Note [Weird fundeps]).  Now I solve first and only
     if that fails try fundeps.  Code is neater too.

     Fixes Trac #7875

  compiler/typecheck/TcInteract.lhs |   60
 ++++++++++++++++++------------------
  1 files changed, 30 insertions(+), 30 deletions(-)
 }}}

-- 
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7875#comment:1
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