Fran Problems

[Steinitz, Dominic J]

I downloaded Fran and had a go at running the demos\test.hs

C:\hugs98>hugs +o
__   __ __  __  ____   ___     _________________________________________
||   || ||  || ||  || ||__     Hugs 98: Based on the Haskell 98 standard
||___|| ||__|| ||__||  __||    Copyright (c) 1994-1999
||---||         ___||          World Wide Web: http://haskell.org/hugs
||   ||                        Report bugs to: hugs-bugs@haskell.org
||   || Version: May 1999      _________________________________________

Hugs mode: Restart with command line option +98 for Haskell 98 mode

Reading file "c:\hugs98\lib\Prelude.hs":

Hugs session for:
c:\hugs98\lib\Prelude.hs
Type :? for help
Prelude>

ERROR "c:\hugs98\lib\Fran\src/ShowFunctions.hs" (line 5): Overlapping
instances
for class "Show"
*** This instance   : Show (a -> b)
*** Overlaps with   : Show (a -> b)
*** Common instance : Show (a -> b)

I edited ShowFunctions to get rid of the overlapping instance:

-- From QuickCheck distribution.

module ShowFunctions where

{-
instance Show (a->b) where
  show f = "<function>"
-}

But then ran into another problem:

Reading file "c:\hugs98\lib\Fran\src/RenderImage.hs":
ERROR "c:\hugs98\lib\Fran\src/RenderImage.hs": Entity "readFile" imported
from m
odule "Win32" already defined in module "Prelude"
SoundB>

I was a bit reluctant to modify Prelude or Win32. Can anyone help? Is it
just that I'm on a back release on Hugs?

Dominic Steinitz


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