How can I write an IO [String] to stdout?

Question

I have an IO [String] in main, which I want to write (as lines) to stdout. How?

--newbie

Thomas M. DuBuisson · Accepted Answer · 2015-02-04 21:57:44Z

9

IO [String] is an action that will get you strings. If you wish to perform the action and print the results then consider:

printIOString io = putStrLn . unlines =<< io

Or with some additional notation, if you prefer:

printIOString io =
  do strs <- io
     let rendered = unlines strs
     putStrLn rendered

answered Feb 4, 2015 at 21:57

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