#![crate_name = "anymap"]
#![crate_type = "lib"]
-#![feature(default_type_params)]
+#![feature(default_type_params, tuple_indexing)]
#![warn(unused_qualifications, non_upper_case_globals,
variant_size_differences, unused_typecasts,
missing_docs, unused_results)]
use std::any::Any;
use std::intrinsics::{forget, TypeId};
use std::collections::HashMap;
+use std::collections::hash_map;
use std::hash::{Hash, Hasher, Writer};
use std::mem::{transmute, transmute_copy};
use std::raw::TraitObject;
+pub use Entry::{Vacant, Occupied};
+
struct TypeIdHasher;
struct TypeIdState {
self.data.contains_key(&TypeId::of::<T>())
}
+ /// Gets the given key's corresponding entry in the map for in-place manipulation
+ pub fn entry<T: Any + 'static>(&mut self) -> Entry<T> {
+ match self.data.entry(TypeId::of::<T>()) {
+ hash_map::Occupied(e) => Occupied(OccupiedEntry { entry: e }),
+ hash_map::Vacant(e) => Vacant(VacantEntry { entry: e }),
+ }
+ }
+
/// Returns the number of items in the collection.
pub fn len(&self) -> uint {
self.data.len()
}
}
+/// A view into a single occupied location in a HashMap
+pub struct OccupiedEntry<'a, V: 'a> {
+ entry: hash_map::OccupiedEntry<'a, TypeId, Box<Any + 'static>>,
+}
+
+/// A view into a single empty location in a HashMap
+pub struct VacantEntry<'a, V: 'a> {
+ entry: hash_map::VacantEntry<'a, TypeId, Box<Any + 'static>>,
+}
+
+/// A view into a single location in a map, which may be vacant or occupied
+pub enum Entry<'a, V: 'a> {
+ /// An occupied Entry
+ Occupied(OccupiedEntry<'a, V>),
+ /// A vacant Entry
+ Vacant(VacantEntry<'a, V>),
+}
+
+impl<'a, V: 'static> OccupiedEntry<'a, V> {
+ /// Gets a reference to the value in the entry
+ pub fn get(&self) -> &V {
+ unsafe { self.entry.get().downcast_ref_unchecked() }
+ }
+
+ /// Gets a mutable reference to the value in the entry
+ pub fn get_mut(&mut self) -> &mut V {
+ unsafe { self.entry.get_mut().downcast_mut_unchecked() }
+ }
+
+ /// Converts the OccupiedEntry into a mutable reference to the value in the entry
+ /// with a lifetime bound to the map itself
+ pub fn into_mut(self) -> &'a mut V {
+ unsafe { self.entry.into_mut().downcast_mut_unchecked() }
+ }
+
+ /// Sets the value of the entry, and returns the entry's old value
+ pub fn set(&mut self, value: V) -> V {
+ unsafe { *self.entry.set(box value as Box<Any + 'static>).downcast_unchecked() }
+ }
+
+ /// Takes the value out of the entry, and returns it
+ pub fn take(self) -> V {
+ unsafe { *self.entry.take().downcast_unchecked() }
+ }
+}
+
+impl<'a, V: 'static> VacantEntry<'a, V> {
+ /// Sets the value of the entry with the VacantEntry's key,
+ /// and returns a mutable reference to it
+ pub fn set(self, value: V) -> &'a mut V {
+ unsafe { self.entry.set(box value as Box<Any + 'static>).downcast_mut_unchecked() }
+ }
+}
+
#[bench]
fn bench_insertion(b: &mut ::test::Bencher) {
b.iter(|| {
}
})
}
+
+#[test]
+fn test_entry() {
+ #[deriving(Show, PartialEq)] struct A(int);
+ #[deriving(Show, PartialEq)] struct B(int);
+ #[deriving(Show, PartialEq)] struct C(int);
+ #[deriving(Show, PartialEq)] struct D(int);
+ #[deriving(Show, PartialEq)] struct E(int);
+ #[deriving(Show, PartialEq)] struct F(int);
+ #[deriving(Show, PartialEq)] struct J(int);
+
+ let mut map: AnyMap = AnyMap::new();
+ assert_eq!(map.insert(A(10)), None);
+ assert_eq!(map.insert(B(20)), None);
+ assert_eq!(map.insert(C(30)), None);
+ assert_eq!(map.insert(D(40)), None);
+ assert_eq!(map.insert(E(50)), None);
+ assert_eq!(map.insert(F(60)), None);
+
+ // Existing key (insert)
+ match map.entry::<A>() {
+ Vacant(_) => unreachable!(),
+ Occupied(mut view) => {
+ assert_eq!(view.get(), &A(10));
+ assert_eq!(view.set(A(100)), A(10));
+ }
+ }
+ assert_eq!(map.get::<A>().unwrap(), &A(100));
+ assert_eq!(map.len(), 6);
+
+
+ // Existing key (update)
+ match map.entry::<B>() {
+ Vacant(_) => unreachable!(),
+ Occupied(mut view) => {
+ let v = view.get_mut();
+ let new_v = B(v.0 * 10);
+ *v = new_v;
+ }
+ }
+ assert_eq!(map.get().unwrap(), &B(200));
+ assert_eq!(map.len(), 6);
+
+
+ // Existing key (take)
+ match map.entry::<C>() {
+ Vacant(_) => unreachable!(),
+ Occupied(view) => {
+ assert_eq!(view.take(), C(30));
+ }
+ }
+ assert_eq!(map.get::<C>(), None);
+ assert_eq!(map.len(), 5);
+
+
+ // Inexistent key (insert)
+ match map.entry::<J>() {
+ Occupied(_) => unreachable!(),
+ Vacant(view) => {
+ assert_eq!(*view.set(J(1000)), J(1000));
+ }
+ }
+ assert_eq!(map.get::<J>().unwrap(), &J(1000));
+ assert_eq!(map.len(), 6);
+}