[GHC] #11715: Constraint vs *

[GHC]

#11715: Constraint vs *
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        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):

 Replying to [comment:34 rwbarton]:
 > I have a hard time believing you'd "like" to do this. Wouldn't it be
 more sensible to use implicit parameters?

 I have a disdain for implicit parameters that stems from the fact that
 their names are represented by strings (`Symbol`s, to be precise), and
 names are not strings in my view, they are unique identifiers declared
 somewhere.

 More importantly, I may want to declare (unexported) data types in this
 module, and instances for those data types may require a context too:

 {{{
 data Helper = ...

 instance Int => Eq Helper where
   ...
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11715#comment:35>
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