[GHC] #11715: Constraint vs *

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Mon Aug 22 23:05:50 UTC 2016


#11715: Constraint vs *
-------------------------------------+-------------------------------------
        Reporter:  bgamari           |                Owner:
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.2.1
       Component:  Compiler (Type    |              Version:  8.0.1-rc1
  checker)                           |
      Resolution:                    |             Keywords:  Typeable
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by int-index):

 Oh, perhaps it's a miscommunication on my behalf. When I say "available in
 the context", by "context" I mean implicit parameters to the left of `=>`.
 So this should not compile:

 {{{#!hs
 f :: Int -> Int
 f x =
   -- error: The 'Int =>' constraint is NOT satisfied by 'x'
   helper

 helper :: Int => Int
 helper = ...
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11715#comment:40>
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