Rust結構

Rust結構

有三種類型的結構(「structs」)，可以使用被struct 關鍵字創建 :

• 元組結構，這是命名爲元組的基礎。
• 典型的 C 結構
• 單元結構，這是無字段，對泛型有用。

// A unit struct
struct Nil;

// A tuple struct
struct Pair(i32, f64);

// A struct with two fields
struct Point {
x: f64,
y: f64,
}

// Structs can be reused as fields of another struct
#[allow(dead_code)]
struct Rectangle {
p1: Point,
p2: Point,
}

fn main() {
// Instantiate a `Point`
let point: Point = Point { x: 0.3, y: 0.4 };

// Access the fields of the point
println!("point coordinates: ({}, {})", point.x, point.y);

// Destructure the point using a \`let\` binding
let Point { x: my\_x, y: my\_y } = point;

let \_rectangle = Rectangle {
    // struct instantiation is an expression too
    p1: Point { x: my\_y, y: my\_x },
    p2: point,
};

// Instantiate a unit struct
let \_nil = Nil;

// Instantiate a tuple struct
let pair = Pair(1, 0.1);

// Destructure a tuple struct
let Pair(integer, decimal) = pair;

println!("pair contains {:?} and {:?}", integer, decimal);

}