mut Keyword 🎯Welcome to our Rust tutorial series! Today, we're diving deep into the mut keyword, a crucial concept in Rust programming. Whether you're a beginner or an intermediate learner, this guide will help you understand the mut keyword thoroughly.
mut Keyword? 📝In Rust, mut is a keyword used to declare that a variable can be mutated or changed after it has been defined. By default, variables in Rust are immutable, meaning they cannot be changed after they've been defined. The mut keyword allows us to change that.
mut? 💡Using mut is essential when you need to change the value of a variable during the execution of your program. For instance, if you're working with user input, a variable to store the input needs to be mutable.
Let's create a simple example to see how mut works:
fn main() {
let mut my_number = 5;
println!("The initial value is: {}", my_number);
my_number = 10;
println!("The new value is: {}", my_number);
}In this example, we've declared a variable my_number with the mut keyword, and we've changed its value inside the main function.
mut, the above code would result in an error because my_number would be immutable.mut doesn't automatically make a variable global. It's still scoped according to its definition.Sometimes, we need to mutate a variable that was initially defined as immutable. This can be achieved with mutable references. We'll cover that in a future tutorial.
What does the `mut` keyword do in Rust?
Stay tuned for our next tutorial, where we'll explore mutable references in Rust! 🎉