[GHC] #7566: exception when loading

[GHC]

#7566: exception when loading
-------------------------+--------------------------------------------------
Reporter:  j4hr0m        |          Owner:          
    Type:  bug           |         Status:  new     
Priority:  normal        |      Component:  Compiler
 Version:  7.6.1         |       Keywords:          
      Os:  Windows       |   Architecture:  x86     
 Failure:  None/Unknown  |      Blockedby:          
Blocking:                |        Related:          
-------------------------+--------------------------------------------------
 when i save

 {{{
 data EinPunkt = Punkt Float Float

 instance (Eq,Show) EinPunkt where
    Punkt x y == Punkt x' y' = x == x' && y == y'
    show Punkt x y = "x: " ++ show x ++ ", y: " ++ show y
 }}}

 as point.hs and load it using WinGHCi 1.0.6 afterwards, i get

 {{{
 > :load "point.hs"
 [1 of 1] Compiling Main             ( point.hs, interpreted )
 *** Exception: compiler\rename\RnSource.lhs:429:14-81: Irrefutable pattern
 failed for pattern Data.Maybe.Just (inst_tyvars,
                                                         _,
                                                         SrcLoc.L _ cls,
                                                         _)
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7566>
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