[Haskell-cafe] Do real programs need IO? (was IO is a bad example for Monads)

Daniel Fischer daniel.is.fischer at web.de
Sun Dec 9 15:54:30 EST 2007

Am Sonntag, 9. Dezember 2007 21:29 schrieb Conal Elliott:
> I think your real point is that some things we still haven't figured out
> how to express functionally.  Right?

That's my point, at least. Currently, AFAIK, the only way to get input and 
produce output is via the IO monad, so it is de facto necessary for all 
'real' programmes, it need not remain so (though I cannot imagine how to 
functionally express 
'readFile "Data.txt" >>= print . performAwfullyCoolFunctionalStuff' - surprise 
me :).
Read "IO is important" as a description of current affairs, not as a claim of 
the inherent grandeur of it.


>  I would certainly agree with that
> part. Perhaps you exaggerating when you wrote "IO is important because you
> can't write any real program without using it."
> Cheers, - Conal

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