"class []" proposal Re: [Haskell-cafe] One thought: Num to 0as ? to list?

[Brian Hulley]

Bulat Ziganshin wrote:
>>> f :: Num a => a -> Int
>>> write as
>>> f :: Num -> Int
>
> so, while this proposal is rather minor, i think that it is Good thing

I wouldn't like it because I'd like to eventually make the class namespace 
separate from the tycon namespace so that I could write:

    class Object a where
            ...

    data Object = forall a. Object a => Object a

etc (this goes with H' proposal that the namespace should always be explicit 
on the module export/import list [1]).

A good editor (hint: the one I'm writing!!!) will be able to highlight the 
uses of "Object" to make it clear which is a class, which is a Tycon, and 
which is a ValueCon, and the operation of replacing a concrete type with a 
class in the type signature to generalise some functions could be made 
easier with a good refactoring tool.

Best regards,
Brian.

[1] 
http://hackage.haskell.org/trac/haskell-prime/wiki/TagExportsWithNamespace
-- 
Logic empowers us and Love gives us purpose.
Yet still phantoms restless for eras long past,
congealed in the present in unthought forms,
strive mightily unseen to destroy us.

http://www.metamilk.com