[GHC] #8813: further support deriving instances Typeable1, Typeable2, etc

[GHC]

#8813: further support deriving instances Typeable1, Typeable2, etc
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        Reporter:  maeder                     |            Owner:
            Type:  task                       |           Status:  closed
        Priority:  normal                     |        Milestone:
       Component:  Compiler                   |          Version:
      Resolution:  wontfix                    |  7.8.1-rc1
Operating System:  Unknown/Multiple           |         Keywords:
 Type of failure:  GHC rejects valid program  |     Architecture:
       Test Case:                             |  Unknown/Multiple
        Blocking:                             |       Difficulty:  Unknown
                                              |       Blocked By:
                                              |  Related Tickets:
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Comment (by rwbarton):

 Well, I think this is a bit silly—you should just write the kind signature
 and forget that `Typeable1` ever existed.

 However, this does appear to work (with `ConstraintKinds`):
 {{{
 type Typeable1 (t :: * -> *) = Typeable t
 class Typeable1 t => C t
 -- *Main> :k C
 -- C :: (* -> *) -> Constraint
 }}}
 so I suppose `Data.Typeable` could export such type synonyms `Typeable1`,
 etc.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8813#comment:11>
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