+//! The raw form of an AnyMap, allowing untyped access.
+//!
+//! All relevant details are in the `RawAnyMap` struct.
+
+use std::any::{Any, TypeId};
+use std::borrow::Borrow;
+use std::collections::hash_map::{self, HashMap};
+use std::collections::hash_state::HashState;
+use std::default::Default;
+use std::hash::{Hash, Hasher};
+use std::iter::IntoIterator;
+use std::mem;
+use std::ops::{Index, IndexMut};
+use std::ptr;
+
+struct TypeIdHasher {
+ value: u64,
+}
+
+struct TypeIdState;
+
+impl HashState for TypeIdState {
+ type Hasher = TypeIdHasher;
+
+ fn hasher(&self) -> TypeIdHasher {
+ TypeIdHasher { value: 0 }
+ }
+}
+
+impl Hasher for TypeIdHasher {
+ #[inline(always)]
+ fn write(&mut self, bytes: &[u8]) {
+ // This expects to receive one and exactly one 64-bit value
+ debug_assert!(bytes.len() == 8);
+ unsafe {
+ ptr::copy_nonoverlapping(&mut self.value, mem::transmute(&bytes[0]), 1)
+ }
+ }
+
+ #[inline(always)]
+ fn finish(&self) -> u64 { self.value }
+}
+
+
+/// The raw, underlying form of an AnyMap.
+///
+/// At its essence, this is a wrapper around `HashMap<TypeId, Box<Any>>`, with the portions that
+/// would be memory-unsafe removed or marked unsafe. Normal people are expected to use the safe
+/// `AnyMap` interface instead, but there is the occasional use for this such as iteration over the
+/// contents of an `AnyMap`. However, because you will then be dealing with `Any` trait objects, it
+/// doesn’t tend to be so very useful. Still, if you need it, it’s here.
+#[derive(Debug)]
+pub struct RawAnyMap {
+ inner: HashMap<TypeId, Box<Any>, TypeIdState>,
+}
+
+impl Default for RawAnyMap {
+ fn default() -> RawAnyMap {
+ RawAnyMap::new()
+ }
+}
+
+impl_common_methods! {
+ field: RawAnyMap.inner;
+ new() => HashMap::with_hash_state(TypeIdState);
+ with_capacity(capacity) => HashMap::with_capacity_and_hash_state(capacity, TypeIdState);
+}
+
+/// RawAnyMap iterator.
+#[derive(Clone)]
+pub struct Iter<'a> {
+ inner: hash_map::Iter<'a, TypeId, Box<Any>>,
+}
+impl<'a> Iterator for Iter<'a> {
+ type Item = &'a Any;
+ #[inline] fn next(&mut self) -> Option<&'a Any> { self.inner.next().map(|x| &**x.1) }
+ #[inline] fn size_hint(&self) -> (usize, Option<usize>) { self.inner.size_hint() }
+}
+impl<'a> ExactSizeIterator for Iter<'a> {
+ #[inline] fn len(&self) -> usize { self.inner.len() }
+}
+
+/// RawAnyMap mutable iterator.
+pub struct IterMut<'a> {
+ inner: hash_map::IterMut<'a, TypeId, Box<Any>>,
+}
+impl<'a> Iterator for IterMut<'a> {
+ type Item = &'a mut Any;
+ #[inline] fn next(&mut self) -> Option<&'a mut Any> { self.inner.next().map(|x| &mut **x.1) }
+ #[inline] fn size_hint(&self) -> (usize, Option<usize>) { self.inner.size_hint() }
+}
+impl<'a> ExactSizeIterator for IterMut<'a> {
+ #[inline] fn len(&self) -> usize { self.inner.len() }
+}
+
+/// RawAnyMap move iterator.
+pub struct IntoIter {
+ inner: hash_map::IntoIter<TypeId, Box<Any>>,
+}
+impl Iterator for IntoIter {
+ type Item = Box<Any>;
+ #[inline] fn next(&mut self) -> Option<Box<Any>> { self.inner.next().map(|x| x.1) }
+ #[inline] fn size_hint(&self) -> (usize, Option<usize>) { self.inner.size_hint() }
+}
+impl ExactSizeIterator for IntoIter {
+ #[inline] fn len(&self) -> usize { self.inner.len() }
+}
+
+/// RawAnyMap drain iterator.
+pub struct Drain<'a> {
+ inner: hash_map::Drain<'a, TypeId, Box<Any>>,
+}
+impl<'a> Iterator for Drain<'a> {
+ type Item = Box<Any>;
+ #[inline] fn next(&mut self) -> Option<Box<Any>> { self.inner.next().map(|x| x.1) }
+ #[inline] fn size_hint(&self) -> (usize, Option<usize>) { self.inner.size_hint() }
+}
+impl<'a> ExactSizeIterator for Drain<'a> {
+ #[inline] fn len(&self) -> usize { self.inner.len() }
+}
+
+impl RawAnyMap {
+ /// An iterator visiting all entries in arbitrary order.
+ ///
+ /// Iterator element type is `&Any`.
+ #[inline]
+ pub fn iter(&self) -> Iter {
+ Iter {
+ inner: self.inner.iter(),
+ }
+ }
+
+ /// An iterator visiting all entries in arbitrary order.
+ ///
+ /// Iterator element type is `&mut Any`.
+ #[inline]
+ pub fn iter_mut(&mut self) -> IterMut {
+ IterMut {
+ inner: self.inner.iter_mut(),
+ }
+ }
+
+ /// Creates a consuming iterator, that is, one that moves each item
+ /// out of the map in arbitrary order. The map cannot be used after
+ /// calling this.
+ ///
+ /// Iterator element type is `Box<Any>`.
+ #[inline]
+ pub fn into_iter(self) -> IntoIter {
+ IntoIter {
+ inner: self.inner.into_iter(),
+ }
+ }
+
+ /// Clears the map, returning all items as an iterator.
+ ///
+ /// Iterator element type is `Box<Any>`.
+ ///
+ /// Keeps the allocated memory for reuse.
+ #[inline]
+ pub fn drain(&mut self) -> Drain {
+ Drain {
+ inner: self.inner.drain(),
+ }
+ }
+
+ /// Gets the entry for the given type in the collection for in-place manipulation.
+ pub fn entry(&mut self, key: TypeId) -> Entry {
+ match self.inner.entry(key) {
+ hash_map::Entry::Occupied(e) => Entry::Occupied(OccupiedEntry {
+ inner: e,
+ }),
+ hash_map::Entry::Vacant(e) => Entry::Vacant(VacantEntry {
+ inner: e,
+ }),
+ }
+ }
+
+ /// Returns a reference to the value corresponding to the key.
+ ///
+ /// The key may be any borrowed form of the map's key type, but `Hash` and `Eq` on the borrowed
+ /// form *must* match those for the key type.
+ pub fn get<Q: ?Sized>(&self, k: &Q) -> Option<&Any>
+ where TypeId: Borrow<Q>, Q: Hash + Eq {
+ self.inner.get(k).map(|x| &**x)
+ }
+
+ /// Returns true if the map contains a value for the specified key.
+ ///
+ /// The key may be any borrowed form of the map's key type, but `Hash` and `Eq` on the borrowed
+ /// form *must* match those for the key type.
+ pub fn contains_key<Q: ?Sized>(&self, k: &Q) -> bool
+ where TypeId: Borrow<Q>, Q: Hash + Eq {
+ self.inner.contains_key(k)
+ }
+
+ /// Returns a mutable reference to the value corresponding to the key.
+ ///
+ /// The key may be any borrowed form of the map's key type, but `Hash` and `Eq` on the borrowed
+ /// form *must* match those for the key type.
+ pub fn get_mut<Q: ?Sized>(&mut self, k: &Q) -> Option<&mut Any>
+ where TypeId: Borrow<Q>, Q: Hash + Eq {
+ self.inner.get_mut(k).map(|x| &mut **x)
+ }
+
+ /// Inserts a key-value pair from the map. If the key already had a value present in the map,
+ /// that value is returned. Otherwise, None is returned.
+ ///
+ /// It is the caller’s responsibility to ensure that the key corresponds with the type ID of
+ /// the value. If they do not, memory safety may be violated.
+ pub unsafe fn insert(&mut self, key: TypeId, value: Box<Any>) -> Option<Box<Any>> {
+ self.inner.insert(key, value)
+ }
+
+ /// Removes a key from the map, returning the value at the key if the key was previously in the
+ /// map.
+ ///
+ /// The key may be any borrowed form of the map's key type, but `Hash` and `Eq` on the borrowed
+ /// form *must* match those for the key type.
+ pub fn remove<Q: ?Sized>(&mut self, k: &Q) -> Option<Box<Any>>
+ where TypeId: Borrow<Q>, Q: Hash + Eq {
+ self.inner.remove(k)
+ }
+
+}
+
+impl<Q: ?Sized> Index<Q> for RawAnyMap where TypeId: Borrow<Q>, Q: Eq + Hash {
+ type Output = Any;
+
+ fn index<'a>(&'a self, index: &Q) -> &'a Any {
+ self.get(index).expect("no entry found for key")
+ }
+}
+
+impl<Q: ?Sized> IndexMut<Q> for RawAnyMap where TypeId: Borrow<Q>, Q: Eq + Hash {
+ fn index_mut<'a>(&'a mut self, index: &Q) -> &'a mut Any {
+ self.get_mut(index).expect("no entry found for key")
+ }
+}
+
+impl IntoIterator for RawAnyMap {
+ type Item = Box<Any>;
+ type IntoIter = IntoIter;
+
+ fn into_iter(self) -> IntoIter {
+ self.into_iter()
+ }
+}
+
+/// A view into a single occupied location in a `RawAnyMap`.
+pub struct OccupiedEntry<'a> {
+ inner: hash_map::OccupiedEntry<'a, TypeId, Box<Any>>,
+}
+
+/// A view into a single empty location in a `RawAnyMap`.
+pub struct VacantEntry<'a> {
+ inner: hash_map::VacantEntry<'a, TypeId, Box<Any>>,
+}
+
+/// A view into a single location in an AnyMap, which may be vacant or occupied.
+pub enum Entry<'a> {
+ /// An occupied Entry
+ Occupied(OccupiedEntry<'a>),
+ /// A vacant Entry
+ Vacant(VacantEntry<'a>),
+}
+
+impl<'a> Entry<'a> {
+ /// Returns a mutable reference to the entry if occupied, or the VacantEntry if vacant.
+ pub fn get(self) -> Result<&'a mut Any, VacantEntry<'a>> {
+ match self {
+ Entry::Occupied(inner) => Ok(inner.into_mut()),
+ Entry::Vacant(inner) => Err(inner),
+ }
+ }
+}
+
+impl<'a> OccupiedEntry<'a> {
+ /// Gets a reference to the value in the entry.
+ pub fn get(&self) -> &Any {
+ &**self.inner.get()
+ }
+
+ /// Gets a mutable reference to the value in the entry.
+ pub fn get_mut(&mut self) -> &mut Any {
+ &mut **self.inner.get_mut()
+ }
+
+ /// Converts the OccupiedEntry into a mutable reference to the value in the entry
+ /// with a lifetime bound to the collection itself.
+ pub fn into_mut(self) -> &'a mut Any {
+ &mut **self.inner.into_mut()
+ }
+
+ /// Sets the value of the entry, and returns the entry's old value.
+ ///
+ /// It is the caller’s responsibility to ensure that the key of the entry corresponds with
+ /// the type ID of `value`. If they do not, memory safety may be violated.
+ pub unsafe fn insert(&mut self, value: Box<Any>) -> Box<Any> {
+ self.inner.insert(value)
+ }
+
+ /// Takes the value out of the entry, and returns it.
+ pub fn remove(self) -> Box<Any> {
+ self.inner.remove()
+ }
+}
+
+impl<'a> VacantEntry<'a> {
+ /// Sets the value of the entry with the VacantEntry's key,
+ /// and returns a mutable reference to it
+ ///
+ /// It is the caller’s responsibility to ensure that the key of the entry corresponds with
+ /// the type ID of `value`. If they do not, memory safety may be violated.
+ pub unsafe fn insert(self, value: Box<Any>) -> &'a mut Any {
+ &mut **self.inner.insert(value)
+ }
+}