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Comment by rapala | Hacker News Reader

Which can then be made to look exactly like the

  getLine >>= putStrLn

case by doing

  greet name = putStrLn ("Hello, " ++ name)
  main = getLine >>= greet

(Edited to include the definition of main)

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This is a nice approach. Thanks to all of you in this thread. I think I'll try something like this when I introduce Haskell I/O in my Programming Languages class in a month or two.

If this is meant to be under main, you need a "let":

    main = do
      let greet name = putStrLn ("Hello, " ++ name)
      getLine >>= greet

For whatever reason, I didn't learn about the magic let syntax in do-notation until relatively late. Anyways this is very elegant, but not something I could have generated early on, especially because it mixes two different sequencing syntaxes (do-notation and >>=).

The 'do' is superfluous.

It would be much better as

    main = let greet name = putStrLn ("Hello, " ++ name)
                in getLine >>= greet

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