Rust FAQ: Top Questions

4. What is borrowing in Rust?

Borrowing allows functions to access variables without taking ownership. This is done through references. Borrowing can be immutable or mutable.

Immutable Borrow: Allows multiple readers.
Mutable Borrow: Allows one writer.

fn main() {
    let mut message = String::from("Hello");
    change(&mut message);
    println!("{}", message);
}

fn change(text: &mut String) {
    text.push_str(", world!");
}

Explanation: Rust enforces borrowing rules to avoid data races and dangling references. You can't have mutable and immutable borrows active at the same time.

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