[GHC] #10708: Rejection of constant functions defined using conditional pattern matching

[GHC]

#10708: Rejection of constant functions defined using conditional pattern matching
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        Reporter:  HubertGaravel     |                   Owner:
            Type:  bug               |                  Status:  closed
        Priority:  normal            |               Milestone:
       Component:  Compiler          |                 Version:  7.10.1
      Resolution:  invalid           |                Keywords:
Operating System:  Linux             |            Architecture:  x86
 Type of failure:  GHC rejects       |               Test Case:
  valid program                      |
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Changes (by goldfire):

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


Comment:

 I believe you mean the code to say this:

 {{{
 data Nat = D0 | Succ Nat
   deriving (Show, Eq, Ord)

 d1 :: Nat
 d2 :: Nat
 d3 :: Nat

 d1 = (Succ D0)
 d2 | D0 == D0 = D0
 d3 | D0 /= D0 = D0
    | (Succ D0) == D0 = D0
    | (Succ D0) /= D0 = (Succ D0)

 main = do
  print d1
  print d2
  print d3
 }}}

 The name of a defined symbol is not repeated in the different branches.

 Thanks for reporting, however!

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10708#comment:1>
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