[Haskell-cafe] Retrospective type-class extension

Tony Morris tonymorris at gmail.com
Thu May 20 02:14:01 EDT 2010


Ivan Miljenovic wrote:
> On 20 May 2010 14:42, Tony Morris <tonymorris at gmail.com> wrote:
>   
>> We all know that "class (Functor f) => Monad f" is preferable but its
>> absence is a historical mistake. We've all probably tried once:
>>
>> instance (Functor f) => Monad f where
>>     
>
> Do you mean the reverse of this (instance (Monad m) => Functor m where) ?
>   
Yes.

-- 
Tony Morris
http://tmorris.net/




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