[Haskell-cafe] Monad transformer, liftIO
Michael Roth
mroth at nessie.de
Fri Apr 3 12:49:36 EDT 2009
Hello list,
maybe I'm just stupid, I'm trying to do something like this:
import Control.Monad
import Control.Monad.Trans
import Control.Monad.List
foobar = do
a <- [1,2,3]
b <- [4,5,6]
liftIO $ putStrLn $ (show a) ++ " " ++ (show b)
return (a+b)
main = do
sums <- foobar
print sums
But this apparently doesn't work... I'm total clueless how
to achieve the correct solution. Maybe my mental image
on the monad transformer thing is totally wrong?
Michael
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