rust

bad_rust_ownership.rs

struct Foo {
    string: String,
    state: i32,
}

// immutable borring N
// mutable - 1 EXCLUSIVE


impl Foo {
    pub fn new(s: String) -> Foo {
        Foo {
            string: s,
            state: 0,
        }
    }
    
    pub fn bar(&mut self) -> i32 {
        let s = &self.string[1..3];
        self.mutate(s);
        self.state
    }
    
    pub fn mutate(&mut self, s: &str) {
        //let s = &self.string[1..3];
        self.state += s.len() as i32;
    }
}



fn main() {
    let s = String::from("Capitan Litva");
    let mut f = Foo::new(s); // "Capitan Litva");
    let result = f.bar();
    
    println!("result = {}", result);
}