Simple IO Monad problem
kuq32tr02 at sneakemail.com
kuq32tr02 at sneakemail.com
Fri Sep 12 23:08:30 EDT 2003
Hello,
I'm starting to use Haskell for writing actual programs using monads and I'm already lost.
I have the following script:
#!/usr/bin/runhugs
> module Main where
> import System(getArgs)
> main = do putStr "Hello, World\n"
> strs <- getArgs
> map putStrLn strs
Which gives the following error:
runhugs: Error occurred
Reading file "./mailalias.lhs":
Reading file "/usr/lib/hugs/lib/System.hs":
Reading file "./mailalias.lhs":
Type checking
ERROR "./mailalias.lhs":5 - Type error in final generator
*** Term : map putStrLn strs
*** Type : [IO ()]
*** Does not match : IO a
Can someone please explain what I'm doing wrong?
Thanks!
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