What is the difference between functors and applicatives in Haskell?

What is the difference between functors and applicatives in Haskell?

In Haskell, a functor is a type class that allows you to apply a function over a wrapped value, while an applicative is a more powerful type class that allows you to apply functions that are also wrapped in a context.

Can you give me an example of a functor in Haskell?

Sure! The Maybe type is a common functor. You can use fmap to apply a function to the value inside a Just, like this: fmap (+1) (Just 2) results in Just 3.

And how does that differ when using an applicative?

With an applicative, you can apply a wrapped function to a wrapped value. For example, if you have Just (+1) and Just 2, you can use <*> to get Just 3.

What are some practical uses of applicatives in Haskell?

Applicatives are useful for combining multiple computations that may fail, like when working with Maybe or Either, allowing you to handle errors gracefully.