[Haskell-beginners] Help! Trapped in the IO Monad!

[Erik de Castro Lopo]

Alexander Dunlap wrote:

> Try removing the "return $" on the last line. foldM ... will already
> be in the IO monad; return will lift the IO a into the IO monad again,
> so you'll have IO (IO a), which you don't want.

Fantastic! Worked a treat.

Thanks,
Erik
-- 
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Erik de Castro Lopo
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"C++ has its place in the history of programming languages. Just
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