What exactly means effective

Question

From time to time I read the term “effect,” but I still cannot give a clear definition of what this means. I assume that the right context is efficient calculations, but I also saw the term spectacular meaning )

I used to think that effective remedies have side effects. But in Haskell there are no side effects (except to some extent IO). There is still efficient computing everywhere.

Then I read that monads are used to create efficient calculations. I can somewhat understand this in the context of the Monad State. But I do not see a side effect in the monad Maybe. All in all, it seems to me that Monads that wrap a functionally similar thing are easier to see as producing side effects than Monads that just wrap a value.

When it comes to functors Applicative, I get even more lost. I have always seen applicative functors as a way of mapfunction with several arguments. Here I do not see a side effect. Or is there a difference between effects and effects?

Answer 1

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Answer 2

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:

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  z = bar y
in foobar z

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  foobar z

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Answer 3

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