########################
Rust
########################

Ownership
****************************************************

https://doc.rust-lang.org/book/ch04-00-understanding-ownership.html

.. code-block:: rust
    
    fn main() {
        let s = String::from("hello");  // s comes into scope
    
        takes_ownership(s);             // s's value moves into the function...
                                        // ... and so is no longer valid here
    
        let x = 5;                      // x comes into scope
    
        makes_copy(x);                  // Because i32 implements the Copy trait,
                                        // x does NOT move into the function,
                                        // so it's okay to use x afterward.
    
    } // Here, x goes out of scope, then s. However, because s's value was moved,
    // nothing special happens.
    
    fn takes_ownership(some_string: String) { // some_string comes into scope
        println!("{some_string}");
    } // Here, some_string goes out of scope and `drop` is called. The backing
    // memory is freed.
    
    fn makes_copy(some_integer: i32) { // some_integer comes into scope
        println!("{some_integer}");
    } // Here, some_integer goes out of scope. Nothing special happens.
    
    
References and Borrowing
********************************************************

https://doc.rust-lang.org/book/ch04-02-references-and-borrowing.html

.. code-block:: rust
    
    fn main() {
        let s1 = String::from("hello");
    
        let len = calculate_length(&s1);
    
        println!("The length of '{s1}' is {len}.");
    }
    
    fn calculate_length(s: &String) -> usize {
        s.len()
    }