monomorphism/hugs98/ghc-5.02.3

Matt Fairtlough Matt Fairtlough <m.fairtlough@dcs.shef.ac.uk>
Fri, 31 May 2002 18:01:47 +0100 (BST)


Hmm.  It might be related but I somehow doubt it.  The buggy program is

------------------------------------------
module Bug2 where

data Bug2 = Bug2

instance Show Bug2 where
showsPrec _ Bug2 str = showChar '?' str
------------------------------------------

(stack overflow on Bug2> Bug2)
and the fix is

------------------------------------------
module Bug2 where

data Bug2 = Bug2

instance Show Bug2 where
  showsPrec _ Bug2 str = showChar '?' str
------------------------------------------


-- an indentation problem.  Quite why globally redefining showsPrec produces
a stack overflow when showing Bug2 values I'll have to leave to the experts.

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