Variables and Mutability

202307032103
Status: #idea
Tags: Rust

Variables and Mutability

Declared using let keyword

Warning

let can only be used inside a function

Immutable by default
- mut keyword is used to make variables mutable

let apples = 5; // Immutable
let mut bananas = 5; // Mutable

Shadowing

Let's you reuse the variable name

let mut guess = String::new();

io::stdin()
    .read_line(&mut guess)
    .expect("Failed to read line");

let guess: u32 = guess.trim().parse().expect("Please type a number!");

Important

Constants are computed at compile-time
Immutable variables are computed at run-time

References

https://rust-book.cs.brown.edu/ch02-00-guessing-game-tutorial.html