Defining Enums

#description

In Rust, an enum, short for "enumeration", is a custom data type that represents a set of possible values or variants. Enums are useful for representing a fixed set of options or states.

To define an enum in Rust, you use the enum keyword followed by the name of the enum and a list of variants enclosed in curly braces.

For example, here is an enum representing different types of animals:

                    
enum Animal {
    Dog,
    Cat,
    Bird,
    Fish,
}

In this enum, Animal is the name of the enum and it has four variants: Dog, Cat, Bird, and Fish.

You can create a variable of type Animal by specifying one of these variants, like so:

                    
let my_pet = Animal::Cat;

You can also attach data to each variant of an enum.

For example, if you wanted to represent different colors of cars, you could define an enum like this:

                    
enum CarColor {
    Red,
    Blue,
    Green,
    Custom(String),
}

In this enum, the Custom variant includes an associated String value to represent a custom color.

To create a variable of type CarColor with the Custom variant and a custom color value, you would specify it like this:

                    
let my_car_color = CarColor::Custom("purple".to_string());

Enums are a powerful tool in Rust for representing fixed sets of options or states, and can be used in many different contexts.

March 27, 2023

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Defining Enums in Rust

Defining Enums