The point of the Haskell style is it makes it easy to control side effects. If you don't care when I/O happens, you can just do everything inside the I/O monad and pretend you're writing Ruby. But if you want to know which functions do I/O and which don't (which can help e.g. test appropriately), Haskell gives you the tools to keep track of that in a lightweight way.
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The point of the Haskell style is it makes it easy to control side effects. If you don't care when I/O happens, you can just do everything inside the I/O monad and pretend you're writing Ruby. But if you want to know which functions do I/O and which don't (which can help e.g. test appropriately), Haskell gives you the tools to keep track of that in a lightweight way.