3 #![allow(non_camel_case_types)]
4 #![allow(non_snake_case)]
7 // Example from lkuper's intern talk, August 2012 -- now with static
9 use Color::{cyan, magenta, yellow, black};
10 use ColorTree::{leaf, branch};
13 fn isEq(a: &Self, b: &Self) -> bool;
16 #[derive(Clone, Copy)]
17 enum Color { cyan, magenta, yellow, black }
19 impl Equal for Color {
20 fn isEq(a: &Color, b: &Color) -> bool {
22 (cyan, cyan) => { true }
23 (magenta, magenta) => { true }
24 (yellow, yellow) => { true }
25 (black, black) => { true }
34 branch(Box<ColorTree>, Box<ColorTree>)
37 impl Equal for ColorTree {
38 fn isEq(a: &ColorTree, b: &ColorTree) -> bool {
40 (&leaf(ref x), &leaf(ref y)) => {
41 Equal::isEq(&(*x).clone(), &(*y).clone())
43 (&branch(ref l1, ref r1), &branch(ref l2, ref r2)) => {
44 Equal::isEq(&(**l1).clone(), &(**l2).clone()) &&
45 Equal::isEq(&(**r1).clone(), &(**r2).clone())
53 assert!(Equal::isEq(&cyan, &cyan));
54 assert!(Equal::isEq(&magenta, &magenta));
55 assert!(!Equal::isEq(&cyan, &yellow));
56 assert!(!Equal::isEq(&magenta, &cyan));
58 assert!(Equal::isEq(&leaf(cyan), &leaf(cyan)));
59 assert!(!Equal::isEq(&leaf(cyan), &leaf(yellow)));
61 assert!(Equal::isEq(&branch(Box::new(leaf(magenta)), Box::new(leaf(cyan))),
62 &branch(Box::new(leaf(magenta)), Box::new(leaf(cyan)))));
64 assert!(!Equal::isEq(&branch(Box::new(leaf(magenta)), Box::new(leaf(cyan))),
65 &branch(Box::new(leaf(magenta)), Box::new(leaf(magenta)))));
67 println!("Assertions all succeeded!");