[Haskell-cafe] Re: deriving

[Christian Maeder]

Anton van Straaten wrote:
> How about making "deriving x" an expression which means:
> 
>   instance x where <compiler implementation>

"deriving Eq" i.e. following "data List a = List a" creates an instance
like:

 instance Eq a => Eq (List a) where <compiler implementation>

The problem was discussed for Stand-alone deriving declarations:

http://www.haskell.org/ghc/docs/latest/html/users_guide/deriving.html

Cheers Christian