struct Point {
x: u64,
y: u64,
}
struct ResizeWH {
width: u64,
height: u64,
}
enum Message {
// TODO: Implement the message variant types based on their usage below.
Resize(ResizeWH),
Move(Point),
Echo(String),
ChangeColor(u8, u8, u8),
Quit
}
struct State {
width: u64,
height: u64,
position: Point,
message: String,
// RGB color composed of red, green and blue.
color: (u8, u8, u8),
quit: bool,
}
impl State {
fn resize(&mut self, width: u64, height: u64) {
self.width = width;
self.height = height;
}
fn move_position(&mut self, point: Point) {
self.position = point;
}
fn echo(&mut self, s: String) {
self.message = s;
}
fn change_color(&mut self, red: u8, green: u8, blue: u8) {
self.color = (red, green, blue);
}
fn quit(&mut self) {
self.quit = true;
}
fn process(&mut self, message: Message) {
// TODO: Create a match expression to process the different message
// variants using the methods defined above.
match message {
Message::Resize(ResizeWH{width, height}) => {
self.resize(width, height);
},
Message::Move(p) => {
self.move_position(p);
},
Message::Echo(strs) => {
self.echo(strs);
},
Message::ChangeColor(a, b, c) => {
self.change_color(a, b, c);
},
Message::Quit => {
self.quit();
}
}
}
}
fn main() {
// You can optionally experiment here.
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_match_message_call() {
let mut state = State {
width: 0,
height: 0,
position: Point { x: 0, y: 0 },
message: String::from("hello world"),
color: (0, 0, 0),
quit: false,
};
state.process(Message::Resize (ResizeWH{
width: 10,
height: 30,
}));
state.process(Message::Move(Point { x: 10, y: 15 }));
state.process(Message::Echo(String::from("Hello world!")));
state.process(Message::ChangeColor(255, 0, 255));
state.process(Message::Quit);
assert_eq!(state.width, 10);
assert_eq!(state.height, 30);
assert_eq!(state.position.x, 10);
assert_eq!(state.position.y, 15);
assert_eq!(state.message, "Hello world!");
assert_eq!(state.color, (255, 0, 255));
assert!(state.quit);
}
}
参考:
https://github.com/rust-lang/rustlings
https://rustwiki.org/zh-CN/book/ch06-01-defining-an-enum.html