[Haskell-cafe] Linguistic hair-splitting

Daniel Fischer daniel.is.fischer at web.de
Thu Jan 28 09:34:02 EST 2010

Am Donnerstag 28 Januar 2010 09:14:38 schrieb Ketil Malde:
> Daniel Fischer <daniel.is.fischer at web.de> writes:
> >> It has been known to call such things 'computations',
> I think "actions" has been used, too, but perhaps mostly for things in
> IO and similar monads?
> >> as opposed to 'values', and even to separate the categories of types
> >> and expressions which deliver the two.
> >
> > As usual, that only works part of the time. [1,4,15,3,7] is not a
> > computation, it's a list of numbers. A plain and simple everyday
> > value.
> But isn't a value of (IO String) equally plain and simple?

Sure, but saying a value of type IO String is "a computation (in the IO 
monad) returning a String" makes more sense to me than saying 
[True,False,True] is "a computation (in the [] monad) returning a Bool".

> I think I prefer (as somebody suggested) "monadic value",

Yes, that works for all monads.

> so that (if
> you want to stress this aspect of its use) the list is a monadic Int
> value in the [] monad, while getLine is a monadic String value in the IO
> monad, and so on.  Maybe.
> -k

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