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Hello

module Main where

Every Haskell program has a Main module. For now, our programs will consist only of a Main module.

Every Haskell program has a main function, where execution begins.

Our first line declares the type of main; we use the standard type for a function that generates output. Our second line defines main as a call to the function print, which outputs a Haskell value.

main ∷ IO ()
main = print "hello"

This program generates the following output. Quotes are included, because the value is output as it would be written in a Haskell program.

"hello"

Main.hs