What are some advanced examples of functors in Haskell?

What are some advanced examples of functors in Haskell?

In Haskell, functors are a powerful abstraction. One advanced example is using the Maybe type as a functor to handle computations that might fail.

Can you explain how Maybe works as a functor?

Sure! The Maybe type can either be Just value or Nothing. As a functor, it allows you to apply a function to the value inside Just, while Nothing remains unchanged.

Are there other functor examples in Haskell?

Yes! Another example is the List type. You can map a function over a list, transforming each element while preserving the structure.

How do I implement a custom functor?

To implement a custom functor, you need to define a type and then create an instance of the Functor typeclass, implementing the fmap function.