[Haskell-cafe] special term describing f :: (Monad m) => (a -> m b)?

Derek Elkins ddarius at hotpop.com
Tue Dec 14 14:24:04 EST 2004


> What is a function of the followning type called:
> 
> f :: (Monad m) => (a -> m b) 
> 
> Is there a special term describing such a function (a function into a
> monad)?
> 
> For f in
> a >>= f
> is en example.
> 
> Need it for an article/report.
> 
> Regards/Henning

Well, formally, it's called a Kleisli arrow (or morphism).  A less
formal term commonly used for values of type a -> m b and m b, is
'computation' or'action' (though 'action' is usually used for the
specific case of IO). In "Notions of Computation and Monads"
Moggi calls them 'commands'.


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