On Sun, May 15, 2011 at 6:58 AM, Michael Snoyman <michael@snoyman.com> wrote:

On Sun, May 15, 2011 at 2:56 PM, aditya siram <aditya.siram@gmail.com> wrote:

You can also try the applicative way:
(<$>) :: (a -> b) -> f a -> f b

import Control.Applicative
-- Think of the <$> as a monadic version of $
main = putStrLn <$> readFile "contents.txt"

Actually, <$> is just a synonym for fmap, so this will have the same problems as the fmap approach.

Michael

Or if you want to chain the functions and not worry about the "contents.txt" argument:

import Control.Monad
main= (readFile >=> putStrLn) "contents.txt"

-deech

On Sun, May 15, 2011 at 1:27 AM, Christopher Howard <christopher.howard@frigidcode.com> wrote:

I understand that one can bind the unwrapped results of IO functions to
variables, and pass them to functions, like so:

main = do filecontents <- readFile "data.txt"
putStrLn filecontents

But does the syntax allow you to cut out the middle man, so to speak,
and bind the results directly to the parameter? Like

-- Tried this and it didn't work.
main = do putStrLn (<- readFile "data.txt")

--
frigidcode.com
theologia.indicium.us

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