On Thu, 8 Jan 2009, Henning Thielemann wrote:
On Fri, 9 Jan 2009, Miguel Mitrofanov wrote:
On 8 Jan 2009, at 23:59, Henning Thielemann wrote:
GHC accepts a class declaration like class Monad (m Maybe) => C m where ... without having any language extension switched on. But it isn't Haskell 98, is it?
It is.
From Report:
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A class assertion has form qtycls tyvar, and indicates the membership of the type tyvar in the class qtycls. A class identifier begins with an uppercase letter. A context consists of zero or more class assertions, and has the general form
( C1 u1, ..., Cn un )
where C1, ..., Cn are class identifiers, and each of the u1, ..., un is either a type variable, or the application of type variable to one or more types.
A nice. I jumped into 4.3 and found
§ § R 32 ©
... copying from Haskell 98 report did not only insert rubbish, but also triggered sending the e-mail. I hope it did not more damage ... scontext -> simpleclass | (simpleclass_1, ..., simpleclass_n) simpleclass -> qtycls tyvar So it must be 'atype' instead of 'tyvar'? Haskell 98 is really mighty.