| use hashbrown::Equivalent; |
| use hashbrown::HashMap; |
| |
| use std::hash::Hash; |
| |
| #[derive(Debug, Hash)] |
| pub struct Pair<A, B>(pub A, pub B); |
| |
| impl<A, B, C, D> PartialEq<(A, B)> for Pair<C, D> |
| where |
| C: PartialEq<A>, |
| D: PartialEq<B>, |
| { |
| fn eq(&self, rhs: &(A, B)) -> bool { |
| self.0 == rhs.0 && self.1 == rhs.1 |
| } |
| } |
| |
| impl<A, B, X> Equivalent<X> for Pair<A, B> |
| where |
| Pair<A, B>: PartialEq<X>, |
| A: Hash + Eq, |
| B: Hash + Eq, |
| { |
| fn equivalent(&self, other: &X) -> bool { |
| *self == *other |
| } |
| } |
| |
| #[test] |
| fn test_lookup() { |
| let s = String::from; |
| let mut map = HashMap::new(); |
| map.insert((s("a"), s("b")), 1); |
| map.insert((s("a"), s("x")), 2); |
| |
| assert!(map.contains_key(&Pair("a", "b"))); |
| assert!(!map.contains_key(&Pair("b", "a"))); |
| } |
| |
| #[test] |
| fn test_string_str() { |
| let s = String::from; |
| let mut map = HashMap::new(); |
| map.insert(s("a"), 1); |
| map.insert(s("b"), 2); |
| map.insert(s("x"), 3); |
| map.insert(s("y"), 4); |
| |
| assert!(map.contains_key("a")); |
| assert!(!map.contains_key("z")); |
| assert_eq!(map.remove("b"), Some(2)); |
| } |