Type sections

Tomasz Zielonka tomasz.zielonka at gmail.com
Mon Dec 11 03:13:34 EST 2006

On Mon, Dec 11, 2006 at 12:40:33AM +0100, Twan van Laarhoven wrote:
> Since operators are allowed in type and class names, I think it would 
> make sense if the section notation was also allowed. In particular the 
> Reader monad would be a little bit nicer:
>  > instance Monad (e ->) where ...
> And maybe type level programming can benefit as well.

I wonder about (-> e) - by analogy to expression sections it could be
desugared to a type-level lambda. AFAIU, type-level lambdas are avoided
when you want terminating type-checking. IIUC, you have an equivalent
power if you turn on certain GHC's extensions. Perhaps with those
extensions we could have type-level lambdas too? Or we have them
already, somehow disguised?

Please tell me, if I am talking nonsense.

Best regards

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