[Haskell-cafe] Re: Functors [Comments from OCaml Hacker Brian Hurt]

Andrew Coppin andrewcoppin at btinternet.com
Sun Jan 18 06:11:20 EST 2009

Heinrich Apfelmus wrote:
> Andrew Coppin wrote:
>>> instance (Monad m) => Functor m where
>>>   fmap f ma = do a <- ma; return (f a)
>> While that's quite interesting from a mathematical point of view, how is
>> this "useful" for programming purposes?
> Surely, you agree that  liftM  is "useful"? Because that's the same thing.

Then why not just use liftM? (That way, you know what it does...)

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