Possible bug in ghc 4.08.1, I leave it to you

[Martin Norbäck]

Hi!

> a :: Show c => c -> Integer
> a err = if b > 0 then error (show err) else 1

> b :: Integer
> b = a "dummy"

This program (although it doesn't do much good), type checks perfectly
in hugs. (I have a larger version which actually does some good as
well).

But in ghc 4.08.1 I get the following error.

    Mismatched contexts
    When matching the contexts of the signatures for `b' and `a'
	(the signature contexts in a mutually recursive group should all be identical)

But where is this requirement in the Haskell report? It might be that I
don't understand what the report says, but this seems like a perfectly
good use to me.

If i remove the type declarations I get errors about c not being general
enough in my code, and in this small example it is mysteriously
instantiated to String!

If you could help me with this problem it would be much appreciated!

	Martin

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SIGBORE: Signature boring error, core dumped