Stage 5.3: Representing Nothing

In other languages, the keyword null is used to represent an absence of a value. It creates difficulty in programming languages because it creates the possibility that our program might fail when interacting with a variable/field.

Rust does not have null, but it is not ignorant of the importance of representing nothing! Consider a naive representation using a tool we already know.

This pattern of providing a None alternative representation for one or many alternate values is so common in Rust because of its lack of a null value. Generic types help solve this challenge.