Table of contents📚
Structs🧱
What is a struct❔
Structs are a way to group related data together in a data type.
How to create a struct❔
We know that an user can have a username, and an email.
So we can create a struct to represent this data instead of having two variables.
To create a struct, we use the keyword struct and then the name of the struct capitalized.
struct User {
username: str,
email: str,
}
ℹ️ structs are declared outside the main function.
ℹ️ We have to specify the type of the variables inside the struct.
How to use a struct🤹
Now that we have a struct we can create an instance of it.
Imagine having an user with the username Bob 🐡 and the email bobthefish@skwal.net.
let bob = User {
username: "Bob 🐡",
email: "bobthefish@gmail.com",
};
We can access the values of the struct by using the dot operator struct.field :
println!("Hello, {} ! We sent you an email at {}", bob.username, bob.email);
Output:
Hello, Bob 🐡 ! We sent you an email at bobthefish@skwal.net
Modifying a struct✏️
By default, like variables, structs are immutable.
So we have to make them mutable by adding the mut keyword before the struct name when creating an instance of it.
let mut bob = User {
username: "Bob 🐡",
email: "bobthefish@gmail.com",
};
bob.username = "Bob 2.0 🐠";
println!("New username : {}", bob.username);
Output:
New username : Bob 2.0 🐠