Re: [GHC] #1702: type operator precedences don't work in contexts

19 Jan 2013

      #1702: type operator precedences don't work in contexts
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  Reporter:  b.hilken@…             |          Owner:                  
      Type:  bug                    |         Status:  closed          
  Priority:  lowest                 |      Milestone:  7.6.2           
 Component:  Compiler               |        Version:  6.8             
Resolution:  fixed                  |       Keywords:                  
        Os:  Unknown/Multiple       |   Architecture:  Unknown/Multiple
   Failure:  None/Unknown           |     Difficulty:  Unknown         
  Testcase:                         |      Blockedby:                  
  Blocking:                         |        Related:                  
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Changes (by monoidal):

  * status:  new => closed
  * failure:  => None/Unknown
  * resolution:  => fixed

Comment:

 The code works fine in 7.6, with a minor change (type operators now do not
 use colons). It might have been fixed when constraint kinds were added. I
 opened #7609 to note a minor formatting error.

 {{{
 {-# LANGUAGE TypeOperators, MultiParamTypeClasses, FlexibleContexts #-}
 data (=:) a b
 data (+:) a b
 class Disjoint a b

 infixr 4 =:
 infixl 3 +:
 infix 2 `Disjoint`

 labelZip :: (n =: a `Disjoint` m =: b)
          => n -> m -> [a] -> [b] -> [n =: a +: m =: b]
 labelZip = undefined
 }}}

-- 
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/1702#comment:16
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