Commit | Line | Data |
---|---|---|
296187ca TW |
1 | use std::ops::{Add, AddAssign}; |
2 | ||
3 | macro_rules! point { | |
4 | ( $x:expr, $y:expr ) => { Point2D { x:$x, y:$y } }; | |
5 | } | |
6 | ||
7 | #[derive(Debug, Copy, Clone, PartialEq)] | |
8 | pub struct Point2D<T> { | |
9 | pub x: T, | |
10 | pub y: T, | |
11 | } | |
12 | ||
13 | impl Point2D<f64> { | |
14 | pub fn length(self) -> f64 { | |
15 | ((self.x * self.x) + (self.y * self.y)).sqrt() | |
16 | } | |
17 | } | |
18 | ||
19 | impl<T: Add<Output=T>> Add for Point2D<T> { | |
20 | type Output = Point2D<T>; | |
21 | ||
22 | fn add(self, rhs: Point2D<T>) -> Self::Output { | |
23 | Point2D { x: self.x + rhs.x, y: self.y + rhs.y } | |
24 | } | |
25 | } | |
26 | ||
27 | impl<T: AddAssign> AddAssign for Point2D<T> { | |
28 | fn add_assign(&mut self, rhs: Point2D<T>) { | |
29 | self.x += rhs.x; | |
30 | self.y += rhs.y; | |
31 | } | |
32 | } | |
33 | ||
34 | #[cfg(test)] | |
35 | mod tests { | |
36 | use super::*; | |
37 | ||
38 | #[test] | |
39 | fn immutable_copy_of_point() { | |
40 | let a = point!(0, 0); | |
41 | let mut b = a; // Copy | |
42 | assert_eq!(a, b); // PartialEq | |
43 | b.x = 1; | |
44 | assert_ne!(a, b); // PartialEq | |
45 | } | |
46 | ||
47 | #[test] | |
48 | fn add_points() { | |
49 | let mut a = point!(1, 0); | |
50 | assert_eq!(a + point!(2, 2), point!(3, 2)); // Add | |
51 | a += point!(2, 2); // AddAssign | |
52 | assert_eq!(a, point!(3, 2)); | |
53 | } | |
54 | } |