Rust logo
Rust 1.44.1
c7087fe00

Mutability

There is a new edition of the book and this is an old link.

Variables are immutable only by default; we can make them mutable by adding mut in front of the variable name.

let mut x = 5;
println!("The value of x is: {}", x);
x = 6;
println!("The value of x is: {}", x);
Run

Here are the relevant sections in the new and old books: