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 themselves wrapped in a context.

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

Sure! The Maybe type is a common example of a functor. You can use fmap to apply a function to the value inside a Just, while Nothing remains unchanged.

What about an example of an applicative?

An example of an applicative is the List type. You can use the <*> operator to apply a list of functions to a list of values, producing all combinations of results.

How do functors and applicatives relate to monads?

Functors and applicatives are both foundational concepts that lead to monads. Monads build on the capabilities of applicatives by adding the ability to chain operations that depend on previous results.