What are lists and functors in Haskell?

What are lists and functors in Haskell?

In Haskell, lists are a fundamental data structure used to store collections of elements. Functors are a type class that allows you to apply a function to values wrapped in a context, like lists.

Can you give me an example of using functors with lists?

Sure! You can use the fmap function to apply a function to each element in a list. For example, fmap (*2) [1, 2, 3] results in [2, 4, 6].

What is the difference between a list and a functor?

A list is a specific data structure, while a functor is a type class that defines how to apply a function over a wrapped value. Lists can be instances of functors.

How do I create a custom functor in Haskell?

To create a custom functor, you need to define a data type and implement the fmap function for it. Here's a simple example with a custom type.