IO happens out of order when using getLine and putStr

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As Michael said, the issue is buffering. By default, output is buffered until you print a newline (or until the buffer is full if you have really long lines), so you’ll most often see this issue when trying to do same-line prompts using putStr like you’re doing.

I suggest defining a small helper function like this to take care of doing the flushing for you:

import System.IO

prompt :: String -> IO String
prompt text = do
    putStr text
    hFlush stdout
    getLine

Now you can simply do

getPoint = do
    xStr <- prompt "Enter x: "
    yStr <- prompt "Enter y: "
    return $ Point (read xStr) (read yStr)

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