[GHC] #2260: Non-ideal error message for misplaced LANGUAGE pragma

[GHC]

#2260: Non-ideal error message for misplaced LANGUAGE pragma
----------------------------------+-----------------------------------------
    Reporter:  TomMD              |       Owner:                  
        Type:  bug                |      Status:  new             
    Priority:  lowest             |   Milestone:  7.6.2           
   Component:  Compiler (Parser)  |     Version:  6.8.2           
    Keywords:                     |          Os:  Unknown/Multiple
Architecture:  Unknown/Multiple   |     Failure:  None/Unknown    
  Difficulty:  Unknown            |    Testcase:                  
   Blockedby:                     |    Blocking:                  
     Related:                     |  
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Comment(by shelarcy):

 GHC 7.x hide T2260.hs' problem. Because GHC 7.0.1 or higher uses Haskell
 2010 in default, and Haskell 2010 supports EmptyDataDecls.

  *
 http://www.haskell.org/ghc/docs/7.0.1/html/users_guide/release-7-0-1.html
  * http://hackage.haskell.org/trac/haskell-
 prime/query?group=status&milestone=Haskell+2010

 We should use Haskell98 to check this ticket's problem.

 {{{
 $ghci T2260.hs -XHaskell98
 GHCi, version 7.4.2: http://www.haskell.org/ghc/  :? for help
 Loading package ghc-prim ... linking ... done.
 Loading package integer-gmp ... linking ... done.
 Loading package base ... linking ... done.
 [1 of 1] Compiling Main             ( T2260.hs, interpreted )

 T2260.hs:5:1:
     `A' has no constructors (-XEmptyDataDecls permits this)
     In the data type declaration for `A'
 Failed, modules loaded: none.
 Prelude> :q
 Leaving GHCi.
 }}}

 {{{
 $ ghci T2260_2.hs
 GHCi, version 7.4.2: http://www.haskell.org/ghc/  :? for help
 Loading package ghc-prim ... linking ... done.
 Loading package integer-gmp ... linking ... done.
 Loading package base ... linking ... done.
 [1 of 1] Compiling Main             ( T2260_2.hs, interpreted )

 T2260_2.hs:6:1:
     `A' has no constructors (-XEmptyDataDecls permits this)
     In the data type declaration for `A'
 Failed, modules loaded: none.
 Prelude> :q
 Leaving GHCi.
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2260#comment:13>
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