[GHC] #11052: Standalone derived Typeable instance for promoted lists is not found

[GHC]

#11052: Standalone derived Typeable instance for promoted lists is not found
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        Reporter:  liamoc            |                Owner:
            Type:  bug               |               Status:  closed
        Priority:  high              |            Milestone:  8.0.1
       Component:  Compiler (Type    |              Version:  7.10.2
  checker)                           |
      Resolution:  fixed             |             Keywords:
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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Changes (by bgamari):

 * status:  new => closed
 * resolution:   => fixed


Comment:

 It appears that the error message has been improved. With `master` as of
 today the test above produces the following error,

 {{{
 $ inplace/bin/ghc-stage2 hi.hs
 [1 of 1] Compiling Test             ( hi.hs, hi.o )

 hi.hs:9:27: error:
     No instance for (Typeable '[]) arising from a use of ‘typeRep’
       GHC can't yet do polykinded Typeable ('[] :: [k1])
     In the first argument of ‘typeRepTyCon’, namely
       ‘(typeRep (Proxy :: Proxy '[]))’
     In the expression: typeRepTyCon (typeRep (Proxy :: Proxy '[]))
     In an equation for ‘nilTyCon’:
         nilTyCon = typeRepTyCon (typeRep (Proxy :: Proxy '[]))

 hi.hs:10:27: error:
     No instance for (Typeable (':)) arising from a use of ‘typeRep’
       GHC can't yet do polykinded Typeable ((':) :: k0 -> [k0] -> [k0])
     In the first argument of ‘typeRepTyCon’, namely
       ‘(typeRep (Proxy :: Proxy (:)))’
     In the expression: typeRepTyCon (typeRep (Proxy :: Proxy (:)))
     In an equation for ‘consTyCon’:
         consTyCon = typeRepTyCon (typeRep (Proxy :: Proxy (:)))
 }}}

 Given that representation of polykinded types is an open research question
 it seems that the bug covered by this issue (the error message) has been
 resolved. Closing.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11052#comment:4>
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