[GHC] #9687: Missing Typeable instances for built-in types

[GHC]

#9687: Missing Typeable instances for built-in types
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              Reporter:  selinger    |            Owner:
                  Type:  bug         |           Status:  new
              Priority:  normal      |        Milestone:
             Component:  Compiler    |          Version:  7.8.3
            Resolution:              |         Keywords:
      Operating System:              |     Architecture:  Unknown/Multiple
  Unknown/Multiple                   |       Difficulty:  Unknown
       Type of failure:              |       Blocked By:
  None/Unknown                       |  Related Tickets:
             Test Case:              |
              Blocking:              |
Differential Revisions:              |
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Comment (by goldfire):

 `Typeable` instances must be for unapplied type constructors. This works:

 {{{
 deriving instance Typeable (,,,,,,,)
 }}}

 But, I agree with the original post that GHC should export `Typeable`
 instances for ''all'' tuples. Otherwise, code like my line above risks
 having an instance collision. Incoherent instances avoids this problem,
 but that's an annoying burden if users have to worry about it.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9687#comment:3>
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