Haskell helloworld example of asynchronous IO.

async-helloworld.hs

import Control.Concurrent
import Control.Concurrent.Async

delayHello n = do
    threadDelay (n * 100)
    let hello = show n ++ ": Hello World!"
    putStrLn hello
    
delayHello :: Int -> IO ()
delayHello n = do
    threadDelay (n * 100)
    let hello = show n ++ ": Hello World!"
    putStrLn hello
    
main :: IO ()
main = sequence_ [delayHello i | i <- [0..1000]]