Rust methods
From wikinotes
Rust lets you add methods to structs
and enums
.
TODO:
other types? what's the full spectrum here?
Associated Functions
Rust lets you add methods to structs/enums using
impl
.
self
is a reference to the instanceSelf
is a reference to the object-typeimpl
allows you to associate functions to an object- you can have as many
impl
blocks as you'd liketype RgbColor{ r: u8, g: u8, b: u8, } impl RgbColor { // ~static-method fn red() -> Self { Self { r: 255, g: 0, b: 0, } } // method fn brighten(&self) { self.r += 8; self.g += 8; self.b += 8; } } // methods let c = RgbColor{r: 8, g: 8, b: 8}; c.brighen(); // {r: 16, g: 16, b: 16} // class methods red = RgbColor::red()Similar to go, you can use the
.
operator to access methods on either a reference or an instance.
rust will automatically dereference it for you.
Traits
You can enforce that types implement a method,
and even provide a default method for them using traits.See more details in rust traits.
struct Cat { name: String } struct Dog { name: String, breed: String } // all implementors of 'Pet' must have method 'play' with this method signature trait Pet { fn play(&self) -> bool; } impl Pet for Cat { fn play(&self) -> bool { println!("you give a ball of yarn to {}", self.name); true } }