#![cfg_attr(not(feature = "std"), no_std)]
use core::any::{Any, TypeId};
+use core::convert::TryInto;
+use core::hash::{Hasher, BuildHasherDefault};
use core::marker::PhantomData;
#[cfg(not(any(feature = "std", feature = "hashbrown")))]
#[cfg(not(feature = "std"))]
use alloc::boxed::Box;
-use raw::RawMap;
use any::{UncheckedAnyExt, IntoBox};
pub use any::CloneAny;
+#[cfg(all(feature = "std", not(feature = "hashbrown")))]
+/// A re-export of [`std::collections::hash_map`] for raw access.
+///
+/// If the `hashbrown` feature gets enabled, this will become an export of `hashbrown::hash_map`.
+///
+/// As with [`RawMap`][crate::RawMap], this is exposed for compatibility reasons, since features
+/// are supposed to be additive. This *is* imperfect, since the two modules are incompatible in a
+/// few places (e.g. hashbrown’s entry types have an extra generic parameter), but it’s close, and
+/// much too useful to give up the whole concept.
+pub use std::collections::hash_map as raw_hash_map;
+
+#[cfg(feature = "hashbrown")]
+/// A re-export of [`hashbrown::hash_map`] for raw access.
+///
+/// If the `hashbrown` feature was disabled, this would become an export of
+/// `std::collections::hash_map`.
+///
+/// As with [`RawMap`][crate::RawMap], this is exposed for compatibility reasons, since features
+/// are supposed to be additive. This *is* imperfect, since the two modules are incompatible in a
+/// few places (e.g. hashbrown’s entry types have an extra generic parameter), but it’s close, and
+/// much too useful to give up the whole concept.
+pub use hashbrown::hash_map as raw_hash_map;
+
+use self::raw_hash_map::HashMap;
+
macro_rules! impl_common_methods {
(
field: $t:ident.$field:ident;
}
mod any;
-pub mod raw;
+
+/// Raw access to the underlying `HashMap`.
+///
+/// This is a public type alias because the underlying `HashMap` could be
+/// `std::collections::HashMap` or `hashbrown::HashMap`, depending on the crate features enabled.
+/// For that reason, you should refer to this type as `anymap::RawMap` rather than
+/// `std::collections::HashMap` to avoid breakage if something else in your crate tree enables
+/// hashbrown.
+///
+/// See also [`raw_hash_map`], an export of the corresponding `hash_map` module.
+pub type RawMap<A> = HashMap<TypeId, Box<A>, BuildHasherDefault<TypeIdHasher>>;
/// A collection containing zero or one values for any given type and allowing convenient,
/// type-safe access to those values.
impl_common_methods! {
field: Map.raw;
- new() => RawMap::new();
- with_capacity(capacity) => RawMap::with_capacity(capacity);
+ new() => RawMap::with_hasher(Default::default());
+ with_capacity(capacity) => RawMap::with_capacity_and_hasher(capacity, Default::default());
}
impl<A: ?Sized + UncheckedAnyExt> Map<A> {
#[inline]
pub fn entry<T: IntoBox<A>>(&mut self) -> Entry<A, T> {
match self.raw.entry(TypeId::of::<T>()) {
- raw::Entry::Occupied(e) => Entry::Occupied(OccupiedEntry {
+ raw_hash_map::Entry::Occupied(e) => Entry::Occupied(OccupiedEntry {
inner: e,
type_: PhantomData,
}),
- raw::Entry::Vacant(e) => Entry::Vacant(VacantEntry {
+ raw_hash_map::Entry::Vacant(e) => Entry::Vacant(VacantEntry {
inner: e,
type_: PhantomData,
}),
}
}
-}
-impl<A: ?Sized + UncheckedAnyExt> Extend<Box<A>> for Map<A> {
+ /// Get access to the raw hash map that backs this.
+ ///
+ /// This will seldom be useful, but it’s conceivable that you could wish to iterate over all
+ /// the items in the collection, and this lets you do that.
+ ///
+ /// To improve compatibility with Cargo features, interact with this map through the names
+ /// [`anymap::RawMap`][RawMap] and [`anymap::raw_hash_map`][raw_hash_map], rather than through
+ /// `std::collections::{HashMap, hash_map}` or `hashbrown::{HashMap, hash_map}`, for anything
+ /// beyond self methods. Otherwise, if you use std and another crate in the tree enables
+ /// hashbrown, your code will break.
#[inline]
- fn extend<T: IntoIterator<Item = Box<A>>>(&mut self, iter: T) {
- for item in iter {
- let _ = unsafe { self.raw.insert(item.type_id(), item) };
- }
+ pub fn as_raw(&self) -> &RawMap<A> {
+ &self.raw
}
-}
-impl<A: ?Sized + UncheckedAnyExt> AsRef<RawMap<A>> for Map<A> {
+ /// Get mutable access to the raw hash map that backs this.
+ ///
+ /// This will seldom be useful, but it’s conceivable that you could wish to iterate over all
+ /// the items in the collection mutably, or drain or something, or *possibly* even batch
+ /// insert, and this lets you do that.
+ ///
+ /// To improve compatibility with Cargo features, interact with this map through the names
+ /// [`anymap::RawMap`][RawMap] and [`anymap::raw_hash_map`][raw_hash_map], rather than through
+ /// `std::collections::{HashMap, hash_map}` or `hashbrown::{HashMap, hash_map}`, for anything
+ /// beyond self methods. Otherwise, if you use std and another crate in the tree enables
+ /// hashbrown, your code will break.
+ ///
+ /// # Safety
+ ///
+ /// If you insert any values to the raw map, the key (a `TypeId`) must match the value’s type,
+ /// or *undefined behaviour* will occur when you access those values.
+ ///
+ /// (*Removing* entries is perfectly safe.)
#[inline]
-
fn as_ref(&self) -> &RawMap<A> {
- &self.raw
+
pub unsafe fn as_raw_mut(&mut self) -> &mut RawMap<A> {
+ &mut self.raw
}
-}
-impl<A: ?Sized + UncheckedAnyExt> AsMut<RawMap<A>> for Map<A> {
+ /// Convert this into the raw hash map that backs this.
+ ///
+ /// This will seldom be useful, but it’s conceivable that you could wish to consume all the
+ /// items in the collection and do *something* with some or all of them, and this lets you do
+ /// that, without the `unsafe` that `.as_raw_mut().drain()` would require.
+ ///
+ /// To improve compatibility with Cargo features, interact with this map through the names
+ /// [`anymap::RawMap`][RawMap] and [`anymap::raw_hash_map`][raw_hash_map], rather than through
+ /// `std::collections::{HashMap, hash_map}` or `hashbrown::{HashMap, hash_map}`, for anything
+ /// beyond self methods. Otherwise, if you use std and another crate in the tree enables
+ /// hashbrown, your code will break.
#[inline]
- fn as_mut(&mut self) -> &mut RawMap<A> {
- &mut self.raw
+ pub fn into_raw(self) -> RawMap<A> {
+ self.raw
+ }
+
+ /// Construct a map from a collection of raw values.
+ ///
+ /// You know what? I can’t immediately think of any legitimate use for this, especially because
+ /// of the requirement of the `BuildHasherDefault<TypeIdHasher>` generic in the map.
+ ///
+ /// Perhaps this will be most practical as `unsafe { Map::from_raw(iter.collect()) }`, iter
+ /// being an iterator over `(TypeId, Box<A>)` pairs. Eh, this method provides symmetry with
+ /// `into_raw`, so I don’t care if literally no one ever uses it. I’m not even going to write a
+ /// test for it, it’s so trivial.
+ ///
+ /// To improve compatibility with Cargo features, interact with this map through the names
+ /// [`anymap::RawMap`][RawMap] and [`anymap::raw_hash_map`][raw_hash_map], rather than through
+ /// `std::collections::{HashMap, hash_map}` or `hashbrown::{HashMap, hash_map}`, for anything
+ /// beyond self methods. Otherwise, if you use std and another crate in the tree enables
+ /// hashbrown, your code will break.
+ ///
+ /// # Safety
+ ///
+ /// For all entries in the raw map, the key (a `TypeId`) must match the value’s type,
+ /// or *undefined behaviour* will occur when you access that entry.
+ #[inline]
+ pub unsafe fn from_raw(raw: RawMap<A>) -> Map<A> {
+ Self { raw }
}
}
-impl<A: ?Sized + UncheckedAnyExt>
From<Map<A>> for RawMap<A> {
+impl<A: ?Sized + UncheckedAnyExt>
Extend<Box<A>> for Map<A> {
#[inline]
- fn from(map: Map<A>) -> RawMap<A> {
- map.raw
+ fn extend<T: IntoIterator<Item = Box<A>>>(&mut self, iter: T) {
+ for item in iter {
+ let _ = self.raw.insert(item.type_id(), item);
+ }
}
}
/// A view into a single occupied location in an `Map`.
pub struct OccupiedEntry<'a, A: ?Sized + UncheckedAnyExt, V: 'a> {
- inner: raw::OccupiedEntry<'a, A>,
+ #[cfg(all(feature = "std", not(feature = "hashbrown")))]
+ inner: raw_hash_map::OccupiedEntry<'a, TypeId, Box<A>>,
+ #[cfg(feature = "hashbrown")]
+ inner: raw_hash_map::OccupiedEntry<'a, TypeId, Box<A>, BuildHasherDefault<TypeIdHasher>>,
type_: PhantomData<V>,
}
/// A view into a single empty location in an `Map`.
pub struct VacantEntry<'a, A: ?Sized + UncheckedAnyExt, V: 'a> {
- inner: raw::VacantEntry<'a, A>,
+ #[cfg(all(feature = "std", not(feature = "hashbrown")))]
+ inner: raw_hash_map::VacantEntry<'a, TypeId, Box<A>>,
+ #[cfg(feature = "hashbrown")]
+ inner: raw_hash_map::VacantEntry<'a, TypeId, Box<A>, BuildHasherDefault<TypeIdHasher>>,
type_: PhantomData<V>,
}
}
}
+/// A hasher designed to eke a little more speed out, given `TypeId`’s known characteristics.
+///
+/// Specifically, this is a no-op hasher that expects to be fed a u64’s worth of
+/// randomly-distributed bits. It works well for `TypeId` (eliminating start-up time, so that my
+/// get_missing benchmark is ~30ns rather than ~900ns, and being a good deal faster after that, so
+/// that my insert_and_get_on_260_types benchmark is ~12μs instead of ~21.5μs), but will
+/// panic in debug mode and always emit zeros in release mode for any other sorts of inputs, so
+/// yeah, don’t use it! 😀
+#[derive(Default)]
+pub struct TypeIdHasher {
+ value: u64,
+}
+
+impl Hasher for TypeIdHasher {
+ #[inline]
+ fn write(&mut self, bytes: &[u8]) {
+ // This expects to receive exactly one 64-bit value, and there’s no realistic chance of
+ // that changing, but I don’t want to depend on something that isn’t expressly part of the
+ // contract for safety. But I’m OK with release builds putting everything in one bucket
+ // if it *did* change (and debug builds panicking).
+ debug_assert_eq!(bytes.len(), 8);
+ let _ = bytes.try_into()
+ .map(|array| self.value = u64::from_ne_bytes(array));
+ }
+
+ #[inline]
+ fn finish(&self) -> u64 { self.value }
+}
+
#[cfg(test)]
mod tests {
use super::*;
assert_debug::<Map<dyn CloneAny + Send>>();
assert_debug::<Map<dyn CloneAny + Send + Sync>>();
}
+
+ #[test]
+ fn type_id_hasher() {
+ #[cfg(not(feature = "std"))]
+ use alloc::vec::Vec;
+ use core::hash::Hash;
+ fn verify_hashing_with(type_id: TypeId) {
+ let mut hasher = TypeIdHasher::default();
+ type_id.hash(&mut hasher);
+ // SAFETY: u64 is valid for all bit patterns.
+ assert_eq!(hasher.finish(), unsafe { core::mem::transmute::<TypeId, u64>(type_id) });
+ }
+ // Pick a variety of types, just to demonstrate it’s all sane. Normal, zero-sized, unsized, &c.
+ verify_hashing_with(TypeId::of::<usize>());
+ verify_hashing_with(TypeId::of::<()>());
+ verify_hashing_with(TypeId::of::<str>());
+ verify_hashing_with(TypeId::of::<&str>());
+ verify_hashing_with(TypeId::of::<Vec<u8>>());
+ }
}
+++ /dev/null
-//! The raw form of a `Map`, allowing untyped access.
-//!
-//! All relevant details are in the `RawMap` struct.
-
-use core::any::{Any, TypeId};
-use core::borrow::Borrow;
-#[cfg(all(feature = "std", not(feature = "hashbrown")))]
-use std::collections::hash_map::{self, HashMap};
-#[cfg(feature = "hashbrown")]
-use hashbrown::hash_map::{self, HashMap};
-#[cfg(not(feature = "std"))]
-use alloc::boxed::Box;
-use core::convert::TryInto;
-use core::hash::Hash;
-use core::hash::{Hasher, BuildHasherDefault};
-use core::ops::{Index, IndexMut};
-
-use crate::any::UncheckedAnyExt;
-
-#[derive(Default)]
-struct TypeIdHasher {
- value: u64,
-}
-
-impl Hasher for TypeIdHasher {
- #[inline]
- fn write(&mut self, bytes: &[u8]) {
- // This expects to receive exactly one 64-bit value, and there’s no realistic chance of
- // that changing, but I don’t want to depend on something that isn’t expressly part of the
- // contract for safety. But I’m OK with release builds putting everything in one bucket
- // if it *did* change (and debug builds panicking).
- debug_assert_eq!(bytes.len(), 8);
- let _ = bytes.try_into()
- .map(|array| self.value = u64::from_ne_bytes(array));
- }
-
- #[inline]
- fn finish(&self) -> u64 { self.value }
-}
-
-#[test]
-fn type_id_hasher() {
- #[cfg(not(feature = "std"))]
- use alloc::vec::Vec;
- fn verify_hashing_with(type_id: TypeId) {
- let mut hasher = TypeIdHasher::default();
- type_id.hash(&mut hasher);
- // SAFETY: u64 is valid for all bit patterns.
- assert_eq!(hasher.finish(), unsafe { core::mem::transmute::<TypeId, u64>(type_id) });
- }
- // Pick a variety of types, just to demonstrate it’s all sane. Normal, zero-sized, unsized, &c.
- verify_hashing_with(TypeId::of::<usize>());
- verify_hashing_with(TypeId::of::<()>());
- verify_hashing_with(TypeId::of::<str>());
- verify_hashing_with(TypeId::of::<&str>());
- verify_hashing_with(TypeId::of::<Vec<u8>>());
-}
-
-/// The raw, underlying form of a `Map`.
-///
-/// 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
-/// `Map` interface instead, but there is the occasional use for this such as iteration over the
-/// contents of an `Map`. 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 RawMap<A: ?Sized + UncheckedAnyExt = dyn Any> {
- inner: HashMap<TypeId, Box<A>, BuildHasherDefault<TypeIdHasher>>,
-}
-
-// #[derive(Clone)] would want A to implement Clone, but in reality it’s only Box<A> that can.
-impl<A: ?Sized + UncheckedAnyExt> Clone for RawMap<A> where Box<A>: Clone {
- #[inline]
- fn clone(&self) -> RawMap<A> {
- RawMap {
- inner: self.inner.clone(),
- }
- }
-}
-
-impl_common_methods! {
- field: RawMap.inner;
- new() => HashMap::with_hasher(Default::default());
- with_capacity(capacity) => HashMap::with_capacity_and_hasher(capacity, Default::default());
-}
-
-/// `RawMap` iterator.
-#[derive(Clone)]
-pub struct Iter<'a, A: ?Sized + UncheckedAnyExt> {
- inner: hash_map::Iter<'a, TypeId, Box<A>>,
-}
-impl<'a, A: ?Sized + UncheckedAnyExt> Iterator for Iter<'a, A> {
- type Item = &'a A;
- #[inline] fn next(&mut self) -> Option<&'a A> { self.inner.next().map(|x| &**x.1) }
- #[inline] fn size_hint(&self) -> (usize, Option<usize>) { self.inner.size_hint() }
-}
-impl<'a, A: ?Sized + UncheckedAnyExt> ExactSizeIterator for Iter<'a, A> {
- #[inline] fn len(&self) -> usize { self.inner.len() }
-}
-
-/// `RawMap` mutable iterator.
-pub struct IterMut<'a, A: ?Sized + UncheckedAnyExt> {
- inner: hash_map::IterMut<'a, TypeId, Box<A>>,
-}
-impl<'a, A: ?Sized + UncheckedAnyExt> Iterator for IterMut<'a, A> {
- type Item = &'a mut A;
- #[inline] fn next(&mut self) -> Option<&'a mut A> { self.inner.next().map(|x| &mut **x.1) }
- #[inline] fn size_hint(&self) -> (usize, Option<usize>) { self.inner.size_hint() }
-}
-impl<'a, A: ?Sized + UncheckedAnyExt> ExactSizeIterator for IterMut<'a, A> {
- #[inline] fn len(&self) -> usize { self.inner.len() }
-}
-
-/// `RawMap` move iterator.
-pub struct IntoIter<A: ?Sized + UncheckedAnyExt> {
- inner: hash_map::IntoIter<TypeId, Box<A>>,
-}
-impl<A: ?Sized + UncheckedAnyExt> Iterator for IntoIter<A> {
- type Item = Box<A>;
- #[inline] fn next(&mut self) -> Option<Box<A>> { self.inner.next().map(|x| x.1) }
- #[inline] fn size_hint(&self) -> (usize, Option<usize>) { self.inner.size_hint() }
-}
-impl<A: ?Sized + UncheckedAnyExt> ExactSizeIterator for IntoIter<A> {
- #[inline] fn len(&self) -> usize { self.inner.len() }
-}
-
-/// `RawMap` drain iterator.
-pub struct Drain<'a, A: ?Sized + UncheckedAnyExt> {
- inner: hash_map::Drain<'a, TypeId, Box<A>>,
-}
-impl<'a, A: ?Sized + UncheckedAnyExt> Iterator for Drain<'a, A> {
- type Item = Box<A>;
- #[inline] fn next(&mut self) -> Option<Box<A>> { self.inner.next().map(|x| x.1) }
- #[inline] fn size_hint(&self) -> (usize, Option<usize>) { self.inner.size_hint() }
-}
-impl<'a, A: ?Sized + UncheckedAnyExt> ExactSizeIterator for Drain<'a, A> {
- #[inline] fn len(&self) -> usize { self.inner.len() }
-}
-
-impl<A: ?Sized + UncheckedAnyExt> RawMap<A> {
- /// An iterator visiting all entries in arbitrary order.
- ///
- /// Iterator element type is `&Any`.
- #[inline]
- pub fn iter(&self) -> Iter<A> {
- 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<A> {
- IterMut {
- inner: self.inner.iter_mut(),
- }
- }
-
- /// 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<A> {
- Drain {
- inner: self.inner.drain(),
- }
- }
-
- /// Gets the entry for the given type in the collection for in-place manipulation.
- #[inline]
- pub fn entry(&mut self, key: TypeId) -> Entry<A> {
- 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.
- #[inline]
- pub fn get<Q: ?Sized>(&self, k: &Q) -> Option<&A>
- 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.
- #[inline]
- 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.
- #[inline]
- pub fn get_mut<Q: ?Sized>(&mut self, k: &Q) -> Option<&mut A>
- 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.
- ///
- /// # Safety
- ///
- /// `key` and the type ID of `value` must match, or *undefined behaviour* occurs.
- #[inline]
- pub unsafe fn insert(&mut self, key: TypeId, value: Box<A>) -> Option<Box<A>> {
- 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.
- #[inline]
- pub fn remove<Q: ?Sized>(&mut self, k: &Q) -> Option<Box<A>>
- where TypeId: Borrow<Q>, Q: Hash + Eq {
- self.inner.remove(k)
- }
-
-}
-
-impl<A: ?Sized + UncheckedAnyExt, Q> Index<Q> for RawMap<A> where TypeId: Borrow<Q>, Q: Eq + Hash {
- type Output = A;
-
- #[inline]
- fn index(&self, index: Q) -> &A {
- self.get(&index).expect("no entry found for key")
- }
-}
-
-impl<A: ?Sized + UncheckedAnyExt, Q> IndexMut<Q> for RawMap<A> where TypeId: Borrow<Q>, Q: Eq + Hash {
- #[inline]
- fn index_mut(&mut self, index: Q) -> &mut A {
- self.get_mut(&index).expect("no entry found for key")
- }
-}
-
-impl<A: ?Sized + UncheckedAnyExt> IntoIterator for RawMap<A> {
- type Item = Box<A>;
- type IntoIter = IntoIter<A>;
-
- #[inline]
- fn into_iter(self) -> IntoIter<A> {
- IntoIter {
- inner: self.inner.into_iter(),
- }
- }
-}
-
-/// A view into a single occupied location in a `RawMap`.
-pub struct OccupiedEntry<'a, A: ?Sized + UncheckedAnyExt> {
- #[cfg(all(feature = "std", not(feature = "hashbrown")))]
- inner: hash_map::OccupiedEntry<'a, TypeId, Box<A>>,
- #[cfg(feature = "hashbrown")]
- inner: hash_map::OccupiedEntry<'a, TypeId, Box<A>, BuildHasherDefault<TypeIdHasher>>,
-}
-
-/// A view into a single empty location in a `RawMap`.
-pub struct VacantEntry<'a, A: ?Sized + UncheckedAnyExt> {
- #[cfg(all(feature = "std", not(feature = "hashbrown")))]
- inner: hash_map::VacantEntry<'a, TypeId, Box<A>>,
- #[cfg(feature = "hashbrown")]
- inner: hash_map::VacantEntry<'a, TypeId, Box<A>, BuildHasherDefault<TypeIdHasher>>,
-}
-
-/// A view into a single location in a `RawMap`, which may be vacant or occupied.
-pub enum Entry<'a, A: ?Sized + UncheckedAnyExt> {
- /// An occupied Entry
- Occupied(OccupiedEntry<'a, A>),
- /// A vacant Entry
- Vacant(VacantEntry<'a, A>),
-}
-
-impl<'a, A: ?Sized + UncheckedAnyExt> Entry<'a, A> {
- /// Ensures a value is in the entry by inserting the default if empty, and returns
- /// a mutable reference to the value in the entry.
- ///
- /// # Safety
- ///
- /// The type ID of `default` must match the entry’s key, or *undefined behaviour* occurs.
- #[inline]
- pub unsafe fn or_insert(self, default: Box<A>) -> &'a mut A {
- match self {
- Entry::Occupied(inner) => inner.into_mut(),
- Entry::Vacant(inner) => inner.insert(default),
- }
- }
-
- /// Ensures a value is in the entry by inserting the result of the default function if empty,
- /// and returns a mutable reference to the value in the entry.
- ///
- /// # Safety
- ///
- /// The type ID of the value returned by `default` must match the entry’s key,
- /// or *undefined behaviour* occurs.
- #[inline]
- pub unsafe fn or_insert_with<F: FnOnce() -> Box<A>>(self, default: F) -> &'a mut A {
- match self {
- Entry::Occupied(inner) => inner.into_mut(),
- Entry::Vacant(inner) => inner.insert(default()),
- }
- }
-}
-
-impl<'a, A: ?Sized + UncheckedAnyExt> OccupiedEntry<'a, A> {
- /// Gets a reference to the value in the entry.
- #[inline]
- pub fn get(&self) -> &A {
- &**self.inner.get()
- }
-
- /// Gets a mutable reference to the value in the entry.
- #[inline]
- pub fn get_mut(&mut self) -> &mut A {
- &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.
- #[inline]
- pub fn into_mut(self) -> &'a mut A {
- &mut **self.inner.into_mut()
- }
-
- /// Sets the value of the entry, and returns the entry's old value.
- ///
- /// # Safety
- ///
- /// The type ID of `value` must match the entry’s key, or *undefined behaviour* occurs.
- #[inline]
- pub unsafe fn insert(&mut self, value: Box<A>) -> Box<A> {
- self.inner.insert(value)
- }
-
- /// Takes the value out of the entry, and returns it.
- #[inline]
- pub fn remove(self) -> Box<A> {
- self.inner.remove()
- }
-}
-
-impl<'a, A: ?Sized + UncheckedAnyExt> VacantEntry<'a, A> {
- /// Sets the value of the entry with the VacantEntry's key,
- /// and returns a mutable reference to it.
- ///
- /// # Safety
- ///
- /// The type ID of `value` must match the entry’s key, or *undefined behaviour* occurs.
- #[inline]
- pub unsafe fn insert(self, value: Box<A>) -> &'a mut A {
- &mut **self.inner.insert(value)
- }
-}