Haskell beginner help

I'm learning haskell and I stumbled upon a problem. Here's the code:

module Main
  where

main = do putStr "Input your name: "
          s <- getLine
          putStrLn s
          main

But after compiling and running, the prompt string doesn't get printed until I input stuff, like this:

foo
Input your name: foo
bar
Input your name: bar

When running the code in the interpreter, everything's alright. What's the problem?

>>13
>>=12
I see what you did there.