Re: [Haskell-beginners] Parsing a file

Hello Francesco, Thanks for your help. Francesco Ariis writes:

Simple quiz: do you understand why

main :: IO () main = "prova"

That returns a String rather than an "IO something".

does nor work (nor compile) while

main :: IO () main = putStrLn "prova"

does?

putStrLn returns an "IO something" and so is campatible with the type of main. Thank you for the help & encouragement. Roger