>
> This is a distilled version of a problem that arose in a student's program:
>
> > f :: a -> a
> > f x = g
> > where
> > g :: a
> > g = x
>
> Reading file "[...]":
> Type checking
> ERROR "[...]" (line 5): Inferred type is not general enough
> *** Expression : g
> *** Expected type : a
> *** Inferred type : _2
>
> Is there a simple explanation for this phenomenon?
The scope of the type variable in the first type declaration
doesn't include the function definition, so the g :: a is
saying that g has to have type all t. t.
Wasn't there once some discussion of the question of making
variables in type declarations for functions range over the
body?
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J�n Fairbairn [EMAIL PROTECTED]
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