//! This crate provides a safe and convenient store for one value of each type.
//!
//! Your starting point is [`Map`]. It has an example.
+//!
+//! # Cargo features
+//!
+//! This crate has two independent features, each of which provides an implementation providing
+//! types `Map`, `AnyMap`, `OccupiedEntry`, `VacantEntry`, `Entry` and `RawMap`:
+//!
+#![cfg_attr(feature = "std", doc = " - **std** (default, *enabled* in this build):")]
+#![cfg_attr(not(feature = "std"), doc = " - **std** (default, *disabled* in this build):")]
+//! an implementation using `std::collections::hash_map`, placed in the crate root
+//! (e.g. `anymap::AnyMap`).
+//!
+#![cfg_attr(feature = "hashbrown", doc = " - **hashbrown** (optional; *enabled* in this build):")]
+#![cfg_attr(not(feature = "hashbrown"), doc = " - **hashbrown** (optional; *disabled* in this build):")]
+//! an implementation using `alloc` and `hashbrown::hash_map`, placed in a module `hashbrown`
+//! (e.g. `anymap::hashbrown::AnyMap`).
#![warn(missing_docs, unused_results)]
#![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")))]
-compile_error!("anymap: you must enable the 'std' feature or the 'hashbrown' feature");
+use core::hash::Hasher;
#[cfg(not(feature = "std"))]
extern crate alloc;
-#[cfg(not(feature = "std"))]
-use alloc::boxed::Box;
+pub use crate::any::CloneAny;
-use any::{UncheckedAnyExt, IntoBox};
-pub use any::CloneAny;
+mod any;
-#[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(any(feature = "std", feature = "hashbrown"))]
+macro_rules! everything {
+ ($example_init:literal, $($parent:ident)::+ $(, $entry_generics:ty)?) => {
+ use core::any::{Any, TypeId};
+ use core::hash::BuildHasherDefault;
+ use core::marker::PhantomData;
-#[cfg(feature = "hashbrown")]
-/// A re-export of [`hashbrown::hash_map`] for raw access.
-///
-/// If the `hashbrown` feature was disabled, this would become an export of
-/// `std::collections::hash_map`.
-///
-/// As with [`RawMap`][crate::RawMap], this is exposed for compatibility reasons, since features
-/// are supposed to be additive. This *is* imperfect, since the two modules are incompatible in a
-/// few places (e.g. hashbrown’s entry types have an extra generic parameter), but it’s close, and
-/// much too useful to give up the whole concept.
-pub use hashbrown::hash_map as raw_hash_map;
+ #[cfg(not(feature = "std"))]
+ use alloc::boxed::Box;
+
+ use ::$($parent)::+::hash_map::{self, HashMap};
+
+ use crate::any::{Downcast, IntoBox};
+
+ /// Raw access to the underlying `HashMap`.
+ ///
+ /// This alias is provided for convenience because of the ugly third generic parameter.
+ 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.
+ ///
+ /// The type parameter `A` allows you to use a different value type; normally you will want
+ /// it to be `core::any::Any` (also known as `std::any::Any`), but there are other choices:
+ ///
+ /// - If you want the entire map to be cloneable, use `CloneAny` instead of `Any`; with
+ /// that, you can only add types that implement `Clone` to the map.
+ /// - You can add on `+ Send` or `+ Send + Sync` (e.g. `Map<dyn Any + Send>`) to add those
+ /// auto traits.
+ ///
+ /// Cumulatively, there are thus six forms of map:
+ ///
+ /// - <code>[Map]<dyn [core::any::Any]></code>,
+ /// also spelled [`AnyMap`] for convenience.
+ /// - <code>[Map]<dyn [core::any::Any] + Send></code>
+ /// - <code>[Map]<dyn [core::any::Any] + Send + Sync></code>
+ /// - <code>[Map]<dyn [CloneAny]></code>
+ /// - <code>[Map]<dyn [CloneAny] + Send></code>
+ /// - <code>[Map]<dyn [CloneAny] + Send + Sync></code>
+ ///
+ /// ## Example
+ ///
+ /// (Here using the [`AnyMap`] convenience alias; the first line could use
+ /// <code>[anymap::Map][Map]::<[core::any::Any]>::new()</code> instead if desired.)
+ ///
+ /// ```rust
+ #[doc = $example_init]
+ /// assert_eq!(data.get(), None::<&i32>);
+ /// data.insert(42i32);
+ /// assert_eq!(data.get(), Some(&42i32));
+ /// data.remove::<i32>();
+ /// assert_eq!(data.get::<i32>(), None);
+ ///
+ /// #[derive(Clone, PartialEq, Debug)]
+ /// struct Foo {
+ /// str: String,
+ /// }
+ ///
+ /// assert_eq!(data.get::<Foo>(), None);
+ /// data.insert(Foo { str: format!("foo") });
+ /// assert_eq!(data.get(), Some(&Foo { str: format!("foo") }));
+ /// data.get_mut::<Foo>().map(|foo| foo.str.push('t'));
+ /// assert_eq!(&*data.get::<Foo>().unwrap().str, "foot");
+ /// ```
+ ///
+ /// Values containing non-static references are not permitted.
+ #[derive(Debug)]
+ pub struct Map<A: ?Sized + Downcast = dyn Any> {
+ raw: RawMap<A>,
+ }
-use self::raw_hash_map::HashMap;
+ // #[derive(Clone)] would want A to implement Clone, but in reality only Box<A> can.
+ impl<A: ?Sized + Downcast> Clone for Map<A> where Box<A>: Clone {
+ #[inline]
+ fn clone(&self) -> Map<A> {
+ Map {
+ raw: self.raw.clone(),
+ }
+ }
+ }
-mod any;
+ /// The most common type of `Map`: just using `Any`; <code>[Map]<dyn [Any]></code>.
+ ///
+ /// Why is this a separate type alias rather than a default value for `Map<A>`?
+ /// `Map::new()` doesn’t seem to be happy to infer that it should go with the default
+ /// value. It’s a bit sad, really. Ah well, I guess this approach will do.
+ pub type AnyMap = Map<dyn Any>;
+
+ impl<A: ?Sized + Downcast> Default for Map<A> {
+ #[inline]
+ fn default() -> Map<A> {
+ Map::new()
+ }
+ }
-/// 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>>;
+ impl<A: ?Sized + Downcast> Map<A> {
+ /// Create an empty collection.
+ #[inline]
+ pub fn new() -> Map<A> {
+ Map {
+ raw: RawMap::with_hasher(Default::default()),
+ }
+ }
-/// A collection containing zero or one values for any given type and allowing convenient,
-/// type-safe access to those values.
-///
-/// The type parameter `A` allows you to use a different value type; normally you will want it to
-/// be `core::any::Any` (also known as `std::any::Any`), but there are other choices:
-///
-/// - If you want the entire map to be cloneable, use `CloneAny` instead of `Any`; with that, you
-/// can only add types that implement `Clone` to the map.
-/// - You can add on `+ Send` or `+ Send + Sync` (e.g. `Map<dyn Any + Send>`) to add those auto
-/// traits.
-///
-/// Cumulatively, there are thus six forms of map:
-///
-/// - <code>[Map]<dyn [core::any::Any]></code>, also spelled [`AnyMap`] for convenience.
-/// - <code>[Map]<dyn [core::any::Any] + Send></code>
-/// - <code>[Map]<dyn [core::any::Any] + Send + Sync></code>
-/// - <code>[Map]<dyn [CloneAny]></code>
-/// - <code>[Map]<dyn [CloneAny] + Send></code>
-/// - <code>[Map]<dyn [CloneAny] + Send + Sync></code>
-///
-/// ## Example
-///
-/// (Here using the [`AnyMap`] convenience alias; the first line could use
-/// <code>[anymap::Map][Map]::<[core::any::Any]>::new()</code> instead if desired.)
-///
-/// ```rust
-/// let mut data = anymap::AnyMap::new();
-/// assert_eq!(data.get(), None::<&i32>);
-/// data.insert(42i32);
-/// assert_eq!(data.get(), Some(&42i32));
-/// data.remove::<i32>();
-/// assert_eq!(data.get::<i32>(), None);
-///
-/// #[derive(Clone, PartialEq, Debug)]
-/// struct Foo {
-/// str: String,
-/// }
-///
-/// assert_eq!(data.get::<Foo>(), None);
-/// data.insert(Foo { str: format!("foo") });
-/// assert_eq!(data.get(), Some(&Foo { str: format!("foo") }));
-/// data.get_mut::<Foo>().map(|foo| foo.str.push('t'));
-/// assert_eq!(&*data.get::<Foo>().unwrap().str, "foot");
-/// ```
-///
-/// Values containing non-static references are not permitted.
-#[derive(Debug)]
-pub struct Map<A: ?Sized + UncheckedAnyExt = dyn Any> {
- raw: RawMap<A>,
-}
+ /// Creates an empty collection with the given initial capacity.
+ #[inline]
+ pub fn with_capacity(capacity: usize) -> Map<A> {
+ Map {
+ raw: RawMap::with_capacity_and_hasher(capacity, Default::default()),
+ }
+ }
-// #[derive(Clone)] would want A to implement Clone, but in reality it’s only Box<A> that can.
-impl<A: ?Sized + UncheckedAnyExt> Clone for Map<A> where Box<A>: Clone {
- #[inline]
- fn clone(&self) -> Map<A> {
- Map {
- raw: self.raw.clone(),
- }
- }
-}
+ /// Returns the number of elements the collection can hold without reallocating.
+ #[inline]
+ pub fn capacity(&self) -> usize {
+ self.raw.capacity()
+ }
-/// The most common type of `Map`: just using `Any`; <code>[Map]<dyn [Any]></code>.
-///
-/// Why is this a separate type alias rather than a default value for `Map<A>`? `Map::new()`
-/// doesn’t seem to be happy to infer that it should go with the default value.
-/// It’s a bit sad, really. Ah well, I guess this approach will do.
-pub type AnyMap = Map<dyn Any>;
+ /// Reserves capacity for at least `additional` more elements to be inserted
+ /// in the collection. The collection may reserve more space to avoid
+ /// frequent reallocations.
+ ///
+ /// # Panics
+ ///
+ /// Panics if the new allocation size overflows `usize`.
+ #[inline]
+ pub fn reserve(&mut self, additional: usize) {
+ self.raw.reserve(additional)
+ }
-impl<A: ?Sized + UncheckedAnyExt> Default for Map<A> {
- #[inline]
- fn default() -> Map<A> {
- Map::new()
- }
-}
+ /// Shrinks the capacity of the collection as much as possible. It will drop
+ /// down as much as possible while maintaining the internal rules
+ /// and possibly leaving some space in accordance with the resize policy.
+ #[inline]
+ pub fn shrink_to_fit(&mut self) {
+ self.raw.shrink_to_fit()
+ }
-impl<A: ?Sized + UncheckedAnyExt> Map<A> {
- /// Create an empty collection.
- #[inline]
- pub fn new() -> Map<A> {
- Map {
- raw: RawMap::with_hasher(Default::default()),
- }
- }
+ // Additional stable methods (as of 1.60.0-nightly) that could be added:
+ // try_reserve(&mut self, additional: usize) -> Result<(), TryReserveError> (1.57.0)
+ // shrink_to(&mut self, min_capacity: usize) (1.56.0)
- /// Creates an empty collection with the given initial capacity.
- #[inline]
- pub fn with_capacity(capacity: usize) -> Map<A> {
- Map {
- raw: RawMap::with_capacity_and_hasher(capacity, Default::default()),
- }
- }
+ /// Returns the number of items in the collection.
+ #[inline]
+ pub fn len(&self) -> usize {
+ self.raw.len()
+ }
- /// Returns the number of elements the collection can hold without reallocating.
- #[inline]
- pub fn capacity(&self) -> usize {
- self.raw.capacity()
- }
+ /// Returns true if there are no items in the collection.
+ #[inline]
+ pub fn is_empty(&self) -> bool {
+ self.raw.is_empty()
+ }
- /// Reserves capacity for at least `additional` more elements to be inserted
- /// in the collection. The collection may reserve more space to avoid
- /// frequent reallocations.
- ///
- /// # Panics
- ///
- /// Panics if the new allocation size overflows `usize`.
- #[inline]
- pub fn reserve(&mut self, additional: usize) {
- self.raw.reserve(additional)
- }
+ /// Removes all items from the collection. Keeps the allocated memory for reuse.
+ #[inline]
+ pub fn clear(&mut self) {
+ self.raw.clear()
+ }
- /// Shrinks the capacity of the collection as much as possible. It will drop
- /// down as much as possible while maintaining the internal rules
- /// and possibly leaving some space in accordance with the resize policy.
- #[inline]
- pub fn shrink_to_fit(&mut self) {
- self.raw.shrink_to_fit()
- }
+ /// Returns a reference to the value stored in the collection for the type `T`,
+ /// if it exists.
+ #[inline]
+ pub fn get<T: IntoBox<A>>(&self) -> Option<&T> {
+ self.raw.get(&TypeId::of::<T>())
+ .map(|any| unsafe { any.downcast_ref_unchecked::<T>() })
+ }
- // Additional stable methods (as of 1.60.0-nightly) that could be added:
- // try_reserve(&mut self, additional: usize) -> Result<(), TryReserveError> (1.57.0)
- // shrink_to(&mut self, min_capacity: usize) (1.56.0)
+ /// Returns a mutable reference to the value stored in the collection for the type `T`,
+ /// if it exists.
+ #[inline]
+ pub fn get_mut<T: IntoBox<A>>(&mut self) -> Option<&mut T> {
+ self.raw.get_mut(&TypeId::of::<T>())
+ .map(|any| unsafe { any.downcast_mut_unchecked::<T>() })
+ }
- /// Returns the number of items in the collection.
- #[inline]
- pub fn len(&self) -> usize {
- self.raw.len()
- }
+ /// Sets the value stored in the collection for the type `T`.
+ /// If the collection already had a value of type `T`, that value is returned.
+ /// Otherwise, `None` is returned.
+ #[inline]
+ pub fn insert<T: IntoBox<A>>(&mut self, value: T) -> Option<T> {
+ self.raw.insert(TypeId::of::<T>(), value.into_box())
+ .map(|any| unsafe { *any.downcast_unchecked::<T>() })
+ }
- /// Returns true if there are no items in the collection.
- #[inline]
- pub fn is_empty(&self) -> bool {
- self.raw.is_empty()
- }
+ // rustc 1.60.0-nightly has another method try_insert that would be nice when stable.
- /// Removes all items from the collection. Keeps the allocated memory for reuse.
- #[inline]
- pub fn clear(&mut self) {
- self.raw.clear()
- }
+ /// Removes the `T` value from the collection,
+ /// returning it if there was one or `None` if there was not.
+ #[inline]
+ pub fn remove<T: IntoBox<A>>(&mut self) -> Option<T> {
+ self.raw.remove(&TypeId::of::<T>())
+ .map(|any| *unsafe { any.downcast_unchecked::<T>() })
+ }
- /// Returns a reference to the value stored in the collection for the type `T`, if it exists.
- #[inline]
- pub fn get<T: IntoBox<A>>(&self) -> Option<&T> {
- self.raw.get(&TypeId::of::<T>())
- .map(|any| unsafe { any.downcast_ref_unchecked::<T>() })
- }
+ /// Returns true if the collection contains a value of type `T`.
+ #[inline]
+ pub fn contains<T: IntoBox<A>>(&self) -> bool {
+ self.raw.contains_key(&TypeId::of::<T>())
+ }
- /// Returns a mutable reference to the value stored in the collection for the type `T`,
- /// if it exists.
- #[inline]
- pub fn get_mut<T: IntoBox<A>>(&mut self) -> Option<&mut T> {
- self.raw.get_mut(&TypeId::of::<T>())
- .map(|any| unsafe { any.downcast_mut_unchecked::<T>() })
- }
+ /// Gets the entry for the given type in the collection for in-place manipulation
+ #[inline]
+ pub fn entry<T: IntoBox<A>>(&mut self) -> Entry<A, T> {
+ match self.raw.entry(TypeId::of::<T>()) {
+ hash_map::Entry::Occupied(e) => Entry::Occupied(OccupiedEntry {
+ inner: e,
+ type_: PhantomData,
+ }),
+ hash_map::Entry::Vacant(e) => Entry::Vacant(VacantEntry {
+ inner: e,
+ type_: PhantomData,
+ }),
+ }
+ }
- /// Sets the value stored in the collection for the type `T`.
- /// If the collection already had a value of type `T`, that value is returned.
- /// Otherwise, `None` is returned.
- #[inline]
- pub fn insert<T: IntoBox<A>>(&mut self, value: T) -> Option<T> {
- unsafe {
- self.raw.insert(TypeId::of::<T>(), value.into_box())
- .map(|any| *any.downcast_unchecked::<T>())
+ /// 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.
+ #[inline]
+ pub fn as_raw(&self) -> &RawMap<A> {
+ &self.raw
+ }
+
+ /// 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.
+ ///
+ /// # 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]
+ pub unsafe fn as_raw_mut(&mut self) -> &mut RawMap<A> {
+ &mut self.raw
+ }
+
+ /// 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.
+ #[inline]
+ 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.
+ ///
+ /// # 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 }
+ }
}
- }
- // rustc 1.60.0-nightly has another method try_insert that would be nice to add when stable.
+ impl<A: ?Sized + Downcast> Extend<Box<A>> for Map<A> {
+ #[inline]
+ fn extend<T: IntoIterator<Item = Box<A>>>(&mut self, iter: T) {
+ for item in iter {
+ let _ = self.raw.insert(Downcast::type_id(&*item), item);
+ }
+ }
+ }
- /// Removes the `T` value from the collection,
- /// returning it if there was one or `None` if there was not.
- #[inline]
- pub fn remove<T: IntoBox<A>>(&mut self) -> Option<T> {
- self.raw.remove(&TypeId::of::<T>())
- .map(|any| *unsafe { any.downcast_unchecked::<T>() })
- }
+ /// A view into a single occupied location in an `Map`.
+ pub struct OccupiedEntry<'a, A: ?Sized + Downcast, V: 'a> {
+ inner: hash_map::OccupiedEntry<'a, TypeId, Box<A>, $($entry_generics)?>,
+ type_: PhantomData<V>,
+ }
- /// Returns true if the collection contains a value of type `T`.
- #[inline]
- pub fn contains<T: IntoBox<A>>(&self) -> bool {
- self.raw.contains_key(&TypeId::of::<T>())
- }
+ /// A view into a single empty location in an `Map`.
+ pub struct VacantEntry<'a, A: ?Sized + Downcast, V: 'a> {
+ inner: hash_map::VacantEntry<'a, TypeId, Box<A>, $($entry_generics)?>,
+ type_: PhantomData<V>,
+ }
- /// Gets the entry for the given type in the collection for in-place manipulation
- #[inline]
- pub fn entry<T: IntoBox<A>>(&mut self) -> Entry<A, T> {
- match self.raw.entry(TypeId::of::<T>()) {
- raw_hash_map::Entry::Occupied(e) => Entry::Occupied(OccupiedEntry {
- inner: e,
- type_: PhantomData,
- }),
- raw_hash_map::Entry::Vacant(e) => Entry::Vacant(VacantEntry {
- inner: e,
- type_: PhantomData,
- }),
+ /// A view into a single location in an `Map`, which may be vacant or occupied.
+ pub enum Entry<'a, A: ?Sized + Downcast, V: 'a> {
+ /// An occupied Entry
+ Occupied(OccupiedEntry<'a, A, V>),
+ /// A vacant Entry
+ Vacant(VacantEntry<'a, A, V>),
}
- }
- /// 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]
- pub fn as_raw(&self) -> &RawMap<A> {
- &self.raw
- }
+ impl<'a, A: ?Sized + Downcast, V: IntoBox<A>> Entry<'a, A, V> {
+ /// Ensures a value is in the entry by inserting the default if empty, and returns
+ /// a mutable reference to the value in the entry.
+ #[inline]
+ pub fn or_insert(self, default: V) -> &'a mut V {
+ match self {
+ Entry::Occupied(inner) => inner.into_mut(),
+ Entry::Vacant(inner) => inner.insert(default),
+ }
+ }
- /// 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]
- pub unsafe fn as_raw_mut(&mut self) -> &mut RawMap<A> {
- &mut self.raw
- }
+ /// 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.
+ #[inline]
+ pub fn or_insert_with<F: FnOnce() -> V>(self, default: F) -> &'a mut V {
+ match self {
+ Entry::Occupied(inner) => inner.into_mut(),
+ Entry::Vacant(inner) => inner.insert(default()),
+ }
+ }
- /// 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]
- pub fn into_raw(self) -> RawMap<A> {
- self.raw
- }
+ /// Ensures a value is in the entry by inserting the default value if empty,
+ /// and returns a mutable reference to the value in the entry.
+ #[inline]
+ pub fn or_default(self) -> &'a mut V where V: Default {
+ match self {
+ Entry::Occupied(inner) => inner.into_mut(),
+ Entry::Vacant(inner) => inner.insert(Default::default()),
+ }
+ }
- /// 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 }
- }
-}
+ /// Provides in-place mutable access to an occupied entry before any potential inserts
+ /// into the map.
+ #[inline]
+ pub fn and_modify<F: FnOnce(&mut V)>(self, f: F) -> Self {
+ match self {
+ Entry::Occupied(mut inner) => {
+ f(inner.get_mut());
+ Entry::Occupied(inner)
+ },
+ Entry::Vacant(inner) => Entry::Vacant(inner),
+ }
+ }
-impl<A: ?Sized + UncheckedAnyExt> Extend<Box<A>> for Map<A> {
- #[inline]
- fn extend<T: IntoIterator<Item = Box<A>>>(&mut self, iter: T) {
- for item in iter {
- let _ = self.raw.insert(item.type_id(), item);
+ // Additional stable methods (as of 1.60.0-nightly) that could be added:
+ // insert_entry(self, value: V) -> OccupiedEntry<'a, K, V> (1.59.0)
}
- }
-}
-/// A view into a single occupied location in an `Map`.
-pub struct OccupiedEntry<'a, A: ?Sized + UncheckedAnyExt, V: '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> {
- #[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>,
-}
+ impl<'a, A: ?Sized + Downcast, V: IntoBox<A>> OccupiedEntry<'a, A, V> {
+ /// Gets a reference to the value in the entry
+ #[inline]
+ pub fn get(&self) -> &V {
+ unsafe { self.inner.get().downcast_ref_unchecked() }
+ }
-/// A view into a single location in an `Map`, which may be vacant or occupied.
-pub enum Entry<'a, A: ?Sized + UncheckedAnyExt, V: 'a> {
- /// An occupied Entry
- Occupied(OccupiedEntry<'a, A, V>),
- /// A vacant Entry
- Vacant(VacantEntry<'a, A, V>),
-}
+ /// Gets a mutable reference to the value in the entry
+ #[inline]
+ pub fn get_mut(&mut self) -> &mut V {
+ unsafe { self.inner.get_mut().downcast_mut_unchecked() }
+ }
-impl<'a, A: ?Sized + UncheckedAnyExt, V: IntoBox<A>> Entry<'a, A, V> {
- /// Ensures a value is in the entry by inserting the default if empty, and returns
- /// a mutable reference to the value in the entry.
- #[inline]
- pub fn or_insert(self, default: V) -> &'a mut V {
- match self {
- Entry::Occupied(inner) => inner.into_mut(),
- Entry::Vacant(inner) => inner.insert(default),
- }
- }
+ /// 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 V {
+ unsafe { self.inner.into_mut().downcast_mut_unchecked() }
+ }
- /// 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.
- #[inline]
- pub fn or_insert_with<F: FnOnce() -> V>(self, default: F) -> &'a mut V {
- match self {
- Entry::Occupied(inner) => inner.into_mut(),
- Entry::Vacant(inner) => inner.insert(default()),
- }
- }
+ /// Sets the value of the entry, and returns the entry's old value
+ #[inline]
+ pub fn insert(&mut self, value: V) -> V {
+ unsafe { *self.inner.insert(value.into_box()).downcast_unchecked() }
+ }
- /// Ensures a value is in the entry by inserting the default value if empty,
- /// and returns a mutable reference to the value in the entry.
- #[inline]
- pub fn or_default(self) -> &'a mut V where V: Default {
- match self {
- Entry::Occupied(inner) => inner.into_mut(),
- Entry::Vacant(inner) => inner.insert(Default::default()),
+ /// Takes the value out of the entry, and returns it
+ #[inline]
+ pub fn remove(self) -> V {
+ unsafe { *self.inner.remove().downcast_unchecked() }
+ }
}
- }
- /// Provides in-place mutable access to an occupied entry before any potential inserts into the
- /// map.
- #[inline]
- // std::collections::hash_map::Entry::and_modify doesn’t have #[must_use], I’ll follow suit.
- #[allow(clippy::return_self_not_must_use)]
- pub fn and_modify<F: FnOnce(&mut V)>(self, f: F) -> Self {
- match self {
- Entry::Occupied(mut inner) => {
- f(inner.get_mut());
- Entry::Occupied(inner)
- },
- Entry::Vacant(inner) => Entry::Vacant(inner),
+ impl<'a, A: ?Sized + Downcast, V: IntoBox<A>> VacantEntry<'a, A, V> {
+ /// Sets the value of the entry with the VacantEntry's key,
+ /// and returns a mutable reference to it
+ #[inline]
+ pub fn insert(self, value: V) -> &'a mut V {
+ unsafe { self.inner.insert(value.into_box()).downcast_mut_unchecked() }
+ }
}
- }
- // Additional stable methods (as of 1.60.0-nightly) that could be added:
- // insert_entry(self, value: V) -> OccupiedEntry<'a, K, V> (1.59.0)
-}
+ #[cfg(test)]
+ mod tests {
+ use crate::CloneAny;
+ use super::*;
+
+ #[derive(Clone, Debug, PartialEq)] struct A(i32);
+ #[derive(Clone, Debug, PartialEq)] struct B(i32);
+ #[derive(Clone, Debug, PartialEq)] struct C(i32);
+ #[derive(Clone, Debug, PartialEq)] struct D(i32);
+ #[derive(Clone, Debug, PartialEq)] struct E(i32);
+ #[derive(Clone, Debug, PartialEq)] struct F(i32);
+ #[derive(Clone, Debug, PartialEq)] struct J(i32);
+
+ macro_rules! test_entry {
+ ($name:ident, $init:ty) => {
+ #[test]
+ fn $name() {
+ let mut map = <$init>::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>() {
+ Entry::Vacant(_) => unreachable!(),
+ Entry::Occupied(mut view) => {
+ assert_eq!(view.get(), &A(10));
+ assert_eq!(view.insert(A(100)), A(10));
+ }
+ }
+ assert_eq!(map.get::<A>().unwrap(), &A(100));
+ assert_eq!(map.len(), 6);
+
+
+ // Existing key (update)
+ match map.entry::<B>() {
+ Entry::Vacant(_) => unreachable!(),
+ Entry::Occupied(mut view) => {
+ let v = view.get_mut();
+ let new_v = B(v.0 * 10);
+ *v = new_v;
+ }
+ }
+ assert_eq!(map.get::<B>().unwrap(), &B(200));
+ assert_eq!(map.len(), 6);
+
+
+ // Existing key (remove)
+ match map.entry::<C>() {
+ Entry::Vacant(_) => unreachable!(),
+ Entry::Occupied(view) => {
+ assert_eq!(view.remove(), C(30));
+ }
+ }
+ assert_eq!(map.get::<C>(), None);
+ assert_eq!(map.len(), 5);
+
+
+ // Inexistent key (insert)
+ match map.entry::<J>() {
+ Entry::Occupied(_) => unreachable!(),
+ Entry::Vacant(view) => {
+ assert_eq!(*view.insert(J(1000)), J(1000));
+ }
+ }
+ assert_eq!(map.get::<J>().unwrap(), &J(1000));
+ assert_eq!(map.len(), 6);
+
+ // Entry.or_insert on existing key
+ map.entry::<B>().or_insert(B(71)).0 += 1;
+ assert_eq!(map.get::<B>().unwrap(), &B(201));
+ assert_eq!(map.len(), 6);
+
+ // Entry.or_insert on nonexisting key
+ map.entry::<C>().or_insert(C(300)).0 += 1;
+ assert_eq!(map.get::<C>().unwrap(), &C(301));
+ assert_eq!(map.len(), 7);
+ }
+ }
+ }
-impl<'a, A: ?Sized + UncheckedAnyExt, V: IntoBox<A>> OccupiedEntry<'a, A, V> {
- /// Gets a reference to the value in the entry
- #[inline]
- pub fn get(&self) -> &V {
- unsafe { self.inner.get().downcast_ref_unchecked() }
- }
+ test_entry!(test_entry_any, AnyMap);
+ test_entry!(test_entry_cloneany, Map<dyn CloneAny>);
- /// Gets a mutable reference to the value in the entry
- #[inline]
- pub fn get_mut(&mut self) -> &mut V {
- unsafe { self.inner.get_mut().downcast_mut_unchecked() }
- }
+ #[test]
+ fn test_default() {
+ let map: AnyMap = Default::default();
+ assert_eq!(map.len(), 0);
+ }
- /// 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 V {
- unsafe { self.inner.into_mut().downcast_mut_unchecked() }
- }
+ #[test]
+ fn test_clone() {
+ let mut map: Map<dyn CloneAny> = Map::new();
+ let _ = map.insert(A(1));
+ let _ = map.insert(B(2));
+ let _ = map.insert(D(3));
+ let _ = map.insert(E(4));
+ let _ = map.insert(F(5));
+ let _ = map.insert(J(6));
+ let map2 = map.clone();
+ assert_eq!(map2.len(), 6);
+ assert_eq!(map2.get::<A>(), Some(&A(1)));
+ assert_eq!(map2.get::<B>(), Some(&B(2)));
+ assert_eq!(map2.get::<C>(), None);
+ assert_eq!(map2.get::<D>(), Some(&D(3)));
+ assert_eq!(map2.get::<E>(), Some(&E(4)));
+ assert_eq!(map2.get::<F>(), Some(&F(5)));
+ assert_eq!(map2.get::<J>(), Some(&J(6)));
+ }
- /// Sets the value of the entry, and returns the entry's old value
- #[inline]
- pub fn insert(&mut self, value: V) -> V {
- unsafe { *self.inner.insert(value.into_box()).downcast_unchecked() }
- }
+ #[test]
+ fn test_varieties() {
+ fn assert_send<T: Send>() { }
+ fn assert_sync<T: Sync>() { }
+ fn assert_clone<T: Clone>() { }
+ fn assert_debug<T: ::core::fmt::Debug>() { }
+ assert_send::<Map<dyn Any + Send>>();
+ assert_send::<Map<dyn Any + Send + Sync>>();
+ assert_sync::<Map<dyn Any + Send + Sync>>();
+ assert_debug::<Map<dyn Any>>();
+ assert_debug::<Map<dyn Any + Send>>();
+ assert_debug::<Map<dyn Any + Send + Sync>>();
+ assert_send::<Map<dyn CloneAny + Send>>();
+ assert_send::<Map<dyn CloneAny + Send + Sync>>();
+ assert_sync::<Map<dyn CloneAny + Send + Sync>>();
+ assert_clone::<Map<dyn CloneAny + Send>>();
+ assert_clone::<Map<dyn CloneAny + Send + Sync>>();
+ assert_clone::<Map<dyn CloneAny + Send + Sync>>();
+ assert_debug::<Map<dyn CloneAny>>();
+ assert_debug::<Map<dyn CloneAny + Send>>();
+ assert_debug::<Map<dyn CloneAny + Send + Sync>>();
+ }
- /// Takes the value out of the entry, and returns it
- #[inline]
- pub fn remove(self) -> V {
- unsafe { *self.inner.remove().downcast_unchecked() }
- }
+ #[test]
+ fn test_extend() {
+ let mut map = AnyMap::new();
+ // (vec![] for 1.36.0 compatibility; more recently, you should use [] instead.)
+ #[cfg(not(feature = "std"))]
+ use alloc::vec;
+ map.extend(vec![Box::new(123) as Box<dyn Any>, Box::new(456), Box::new(true)]);
+ assert_eq!(map.get(), Some(&456));
+ assert_eq!(map.get::<bool>(), Some(&true));
+ assert!(map.get::<Box<dyn Any>>().is_none());
+ }
+ }
+ };
}
-impl<'a, A: ?Sized + UncheckedAnyExt, V: IntoBox<A>> VacantEntry<'a, A, V> {
- /// Sets the value of the entry with the VacantEntry's key,
- /// and returns a mutable reference to it
- #[inline]
- pub fn insert(self, value: V) -> &'a mut V {
- unsafe { self.inner.insert(value.into_box()).downcast_mut_unchecked() }
- }
+#[cfg(feature = "std")]
+everything!(
+ "let mut data = anymap::AnyMap::new();",
+ std::collections
+);
+
+#[cfg(feature = "hashbrown")]
+/// AnyMap backed by `hashbrown`.
+///
+/// This depends on the `hashbrown` Cargo feature being enabled.
+pub mod hashbrown {
+ use crate::TypeIdHasher;
+ #[cfg(doc)]
+ use crate::any::CloneAny;
+
+ everything!(
+ "let mut data = anymap::hashbrown::AnyMap::new();",
+ hashbrown,
+ BuildHasherDefault<TypeIdHasher>
+ );
}
/// A hasher designed to eke a little more speed out, given `TypeId`’s known characteristics.
fn finish(&self) -> u64 { self.value }
}
-#[cfg(test)]
-mod tests {
- use super::*;
-
- #[derive(Clone, Debug, PartialEq)] struct A(i32);
- #[derive(Clone, Debug, PartialEq)] struct B(i32);
- #[derive(Clone, Debug, PartialEq)] struct C(i32);
- #[derive(Clone, Debug, PartialEq)] struct D(i32);
- #[derive(Clone, Debug, PartialEq)] struct E(i32);
- #[derive(Clone, Debug, PartialEq)] struct F(i32);
- #[derive(Clone, Debug, PartialEq)] struct J(i32);
-
- macro_rules! test_entry {
- ($name:ident, $init:ty) => {
- #[test]
- fn $name() {
- let mut map = <$init>::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>() {
- Entry::Vacant(_) => unreachable!(),
- Entry::Occupied(mut view) => {
- assert_eq!(view.get(), &A(10));
- assert_eq!(view.insert(A(100)), A(10));
- }
- }
- assert_eq!(map.get::<A>().unwrap(), &A(100));
- assert_eq!(map.len(), 6);
-
-
- // Existing key (update)
- match map.entry::<B>() {
- Entry::Vacant(_) => unreachable!(),
- Entry::Occupied(mut view) => {
- let v = view.get_mut();
- let new_v = B(v.0 * 10);
- *v = new_v;
- }
- }
- assert_eq!(map.get::<B>().unwrap(), &B(200));
- assert_eq!(map.len(), 6);
-
-
- // Existing key (remove)
- match map.entry::<C>() {
- Entry::Vacant(_) => unreachable!(),
- Entry::Occupied(view) => {
- assert_eq!(view.remove(), C(30));
- }
- }
- assert_eq!(map.get::<C>(), None);
- assert_eq!(map.len(), 5);
-
-
- // Inexistent key (insert)
- match map.entry::<J>() {
- Entry::Occupied(_) => unreachable!(),
- Entry::Vacant(view) => {
- assert_eq!(*view.insert(J(1000)), J(1000));
- }
- }
- assert_eq!(map.get::<J>().unwrap(), &J(1000));
- assert_eq!(map.len(), 6);
-
- // Entry.or_insert on existing key
- map.entry::<B>().or_insert(B(71)).0 += 1;
- assert_eq!(map.get::<B>().unwrap(), &B(201));
- assert_eq!(map.len(), 6);
-
- // Entry.or_insert on nonexisting key
- map.entry::<C>().or_insert(C(300)).0 += 1;
- assert_eq!(map.get::<C>().unwrap(), &C(301));
- assert_eq!(map.len(), 7);
- }
- }
- }
-
- test_entry!(test_entry_any, AnyMap);
- test_entry!(test_entry_cloneany, Map<dyn CloneAny>);
-
- #[test]
- fn test_default() {
- let map: AnyMap = Default::default();
- assert_eq!(map.len(), 0);
- }
-
- #[test]
- fn test_clone() {
- let mut map: Map<dyn CloneAny> = Map::new();
- let _ = map.insert(A(1));
- let _ = map.insert(B(2));
- let _ = map.insert(D(3));
- let _ = map.insert(E(4));
- let _ = map.insert(F(5));
- let _ = map.insert(J(6));
- let map2 = map.clone();
- assert_eq!(map2.len(), 6);
- assert_eq!(map2.get::<A>(), Some(&A(1)));
- assert_eq!(map2.get::<B>(), Some(&B(2)));
- assert_eq!(map2.get::<C>(), None);
- assert_eq!(map2.get::<D>(), Some(&D(3)));
- assert_eq!(map2.get::<E>(), Some(&E(4)));
- assert_eq!(map2.get::<F>(), Some(&F(5)));
- assert_eq!(map2.get::<J>(), Some(&J(6)));
- }
-
- #[test]
- fn test_varieties() {
- fn assert_send<T: Send>() { }
- fn assert_sync<T: Sync>() { }
- fn assert_clone<T: Clone>() { }
- fn assert_debug<T: ::core::fmt::Debug>() { }
- assert_send::<Map<dyn Any + Send>>();
- assert_send::<Map<dyn Any + Send + Sync>>();
- assert_sync::<Map<dyn Any + Send + Sync>>();
- assert_debug::<Map<dyn Any>>();
- assert_debug::<Map<dyn Any + Send>>();
- assert_debug::<Map<dyn Any + Send + Sync>>();
- assert_send::<Map<dyn CloneAny + Send>>();
- assert_send::<Map<dyn CloneAny + Send + Sync>>();
- assert_sync::<Map<dyn CloneAny + Send + Sync>>();
- assert_clone::<Map<dyn CloneAny + Send>>();
- assert_clone::<Map<dyn CloneAny + Send + Sync>>();
- assert_clone::<Map<dyn CloneAny + Send + Sync>>();
- assert_debug::<Map<dyn CloneAny>>();
- 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>>());
- }
+#[test]
+fn type_id_hasher() {
+ #[cfg(not(feature = "std"))]
+ use alloc::vec::Vec;
+ use core::hash::Hash;
+ use core::any::TypeId;
+ 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>>());
}