Immutable and Mutable References

Snippet

Immutable and Mutable References

Rust uses references to allow access to data without taking ownership. Immutable references (&T) allow reading but not modifying. Mutable references (&mut T) allow both reading and modifying, but you can only have ONE mutable reference at a time - this prevents data races at compile time.

snippet.rs
rust
fn main() {
    let mut data = vec![1, 2, 3];
    
    let immut_ref = &data;
    println!("Immutable: {:?}", immut_ref);
    
    let mut_ref = &mut data;
    mut_ref.push(4);
    println!("Mutable: {:?}", mut_ref);
}

Breakdown

let mut data = vec![1, 2, 3];

Creates a mutable vector with three elements

let immut_ref = &data;

Creates an immutable reference to data

let mut_ref = &mut data;

Creates a mutable reference - exclusive access

mut_ref.push(4);

Modifies the data through the mutable reference

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Immutable and Mutable References

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