Monads
Steve was excited about functors but still struggled to see their full potential in his game logic. Julia knew it was time to introduce monads.
Julia: Let’s take your game’s upgrade system a step further. Imagine a series of operations: checking the player’s gold, deducting the cost, and applying the upgrade. Each step depends on the previous one succeeding. This is where monads shine.
Steve: That sounds exactly like what I need for my upgrade system. How do monads handle this?
A monad represents an evolution of the concepts we explored with functors and applicative functors. While a functor allows us to map a function over a wrapped value and an applicative functor enables applying wrapped functions to wrapped values, monads introduce the ability to chain operations in a way that handles the context of those operations—be it errors, lists, options, or other computational contexts. Thus, we can say that a monad is an applicative functor that...