fffej / learning-rust

Just a repo so I can work through "Programming Rust 2nd Edition"

Notes are for me, so probably won't make any sense to anyone else, sorry! (Chapter 5. References)

Rust aims to be safe and performant by restricting how you use pointers. Ownership is built into the language and enforced by compile-time checks. Deterministic finalization without having to remember to do it (like in C++)! Variables own values.

You can transfer ownership

  let s = vec!["a".to_string(), "b".to_string()];
  let t = s; // this is a move, s is illegal now
  let u = s; // compile time problem

If you want to do stuff like the above use .clone().

  let mut a = "banana".to_string();
  b = "apple".to_string(); // banana dropped

• i8 through i128 (and corresponding u) for ints of given width.
• f32 and f64 for floating points
• bool, char, struct as you'd expect
• Option<&>, Result<T,Error>
• | a, b, c | (closure)
• ("banana", 33) - tuple of type (&str, i32)
• fn swap<T>(x: &mut T, y: &mut T); - generic swap function on type T (return type omitted since unit)
• &T is an immutable reference to a T (like a pointer, * dereferences)
• &mut T is a mutable EXCLUSIVE reference.
• Allocate on the head with Box::new(t)
• type is like typedef