Re: [GHC] #10027: Importing constructor of associated data type fails

28 Jan 2015

      #10027: Importing constructor of associated data type fails
-------------------------------------+-------------------------------------
        Reporter:  lspitzner         |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.8.4
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |  constructor import associated data
 Type of failure:  None/Unknown      |  type
      Blocked By:                    |            Architecture:
 Related Tickets:                    |  Unknown/Multiple
                                     |               Test Case:
                                     |                Blocking:
                                     |  Differential Revisions:
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Comment (by simonpj):

 Re comment:2, yes, you are right, I'd forgotten that. The remaining
 infelicity is that if the data type has 200 constructors, you'll have to
 say
 {{{
 import M( pattern C1, pattern C2, ..., pattern C200 )
 }}}
 rather than
 {{{
 import M( T(..) )
 }}}
 But perhaps this will happen so seldom that we don't care.

 Partly it's a question of matching is it ''surprising'' that you module B
 above does not export D?  Or would it be surprising if it ''did'' export
 it?

--
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10027#comment:4
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