[GHC] #8021: Multiple constraint classes - the alternative to superclass

[GHC]

#8021: Multiple constraint classes - the alternative to superclass
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        Reporter:  wvv               |            Owner:
            Type:  feature request   |           Status:  new
        Priority:  normal            |        Milestone:
       Component:  Compiler          |          Version:  7.6.3
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown      |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
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Comment (by wvv):

 And this is only tip of the iceberg.

 Now we have discussion about

 (Monad m) vs. (Functor m => Monad m).

 With class interfaces it is not an option: we have them both(!!!)


 {{{

   class Monad m where ...

   class Functor m => Applicative m => Monad m where ..

 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8021#comment:7>
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