560a73da42b56e7837cb9e4f1ace597ceff4f5b9
1 //! This crate provides a safe and convenient store for one value of each type.
3 //! Your starting point is [`Map`]. It has an example.
5 #![warn(missing_docs, unused_results)]
7 #![cfg_attr(not(feature = "std"), no_std)]
9 use core
::any
::{Any
, TypeId
};
10 use core
::convert
::TryInto
;
11 use core
::hash
::{Hasher
, BuildHasherDefault
};
12 use core
::marker
::PhantomData
;
14 #[cfg(not(any(feature = "std", feature = "hashbrown")))]
15 compile_error!("anymap: you must enable the 'std' feature or the 'hashbrown' feature");
17 #[cfg(not(feature = "std"))]
20 #[cfg(not(feature = "std"))]
21 use alloc
::boxed
::Box
;
23 use any
::{Downcast
, IntoBox
};
24 pub use any
::CloneAny
;
26 #[cfg(all(feature = "std", not(feature = "hashbrown")))]
27 /// A re-export of [`std::collections::hash_map`] for raw access.
29 /// If the `hashbrown` feature gets enabled, this will become an export of `hashbrown::hash_map`.
31 /// As with [`RawMap`][crate::RawMap], this is exposed for compatibility reasons, since features
32 /// are supposed to be additive. This *is* imperfect, since the two modules are incompatible in a
33 /// few places (e.g. hashbrown’s entry types have an extra generic parameter), but it’s close, and
34 /// much too useful to give up the whole concept.
35 pub use std
::collections
::hash_map
as raw_hash_map
;
37 #[cfg(feature = "hashbrown")]
38 /// A re-export of [`hashbrown::hash_map`] for raw access.
40 /// If the `hashbrown` feature was disabled, this would become an export of
41 /// `std::collections::hash_map`.
43 /// As with [`RawMap`][crate::RawMap], this is exposed for compatibility reasons, since features
44 /// are supposed to be additive. This *is* imperfect, since the two modules are incompatible in a
45 /// few places (e.g. hashbrown’s entry types have an extra generic parameter), but it’s close, and
46 /// much too useful to give up the whole concept.
47 pub use hashbrown
::hash_map
as raw_hash_map
;
49 use self::raw_hash_map
::HashMap
;
53 /// Raw access to the underlying `HashMap`.
55 /// This is a public type alias because the underlying `HashMap` could be
56 /// `std::collections::HashMap` or `hashbrown::HashMap`, depending on the crate features enabled.
57 /// For that reason, you should refer to this type as `anymap::RawMap` rather than
58 /// `std::collections::HashMap` to avoid breakage if something else in your crate tree enables
61 /// See also [`raw_hash_map`], an export of the corresponding `hash_map` module.
62 pub type RawMap
<A
> = HashMap
<TypeId
, Box
<A
>, BuildHasherDefault
<TypeIdHasher
>>;
64 /// A collection containing zero or one values for any given type and allowing convenient,
65 /// type-safe access to those values.
67 /// The type parameter `A` allows you to use a different value type; normally you will want it to
68 /// be `core::any::Any` (also known as `std::any::Any`), but there are other choices:
70 /// - If you want the entire map to be cloneable, use `CloneAny` instead of `Any`; with that, you
71 /// can only add types that implement `Clone` to the map.
72 /// - You can add on `+ Send` or `+ Send + Sync` (e.g. `Map<dyn Any + Send>`) to add those auto
75 /// Cumulatively, there are thus six forms of map:
77 /// - <code>[Map]<dyn [core::any::Any]></code>, also spelled [`AnyMap`] for convenience.
78 /// - <code>[Map]<dyn [core::any::Any] + Send></code>
79 /// - <code>[Map]<dyn [core::any::Any] + Send + Sync></code>
80 /// - <code>[Map]<dyn [CloneAny]></code>
81 /// - <code>[Map]<dyn [CloneAny] + Send></code>
82 /// - <code>[Map]<dyn [CloneAny] + Send + Sync></code>
86 /// (Here using the [`AnyMap`] convenience alias; the first line could use
87 /// <code>[anymap::Map][Map]::<[core::any::Any]>::new()</code> instead if desired.)
90 /// let mut data = anymap::AnyMap::new();
91 /// assert_eq!(data.get(), None::<&i32>);
92 /// data.insert(42i32);
93 /// assert_eq!(data.get(), Some(&42i32));
94 /// data.remove::<i32>();
95 /// assert_eq!(data.get::<i32>(), None);
97 /// #[derive(Clone, PartialEq, Debug)]
102 /// assert_eq!(data.get::<Foo>(), None);
103 /// data.insert(Foo { str: format!("foo") });
104 /// assert_eq!(data.get(), Some(&Foo { str: format!("foo") }));
105 /// data.get_mut::<Foo>().map(|foo| foo.str.push('t'));
106 /// assert_eq!(&*data.get::<Foo>().unwrap().str, "foot");
109 /// Values containing non-static references are not permitted.
111 pub struct Map
<A
: ?Sized
+ Downcast
= dyn Any
> {
115 // #[derive(Clone)] would want A to implement Clone, but in reality it’s only Box<A> that can.
116 impl<A
: ?Sized
+ Downcast
> Clone
for Map
<A
> where Box
<A
>: Clone
{
118 fn clone(&self) -> Map
<A
> {
120 raw
: self.raw
.clone(),
125 /// The most common type of `Map`: just using `Any`; <code>[Map]<dyn [Any]></code>.
127 /// Why is this a separate type alias rather than a default value for `Map<A>`? `Map::new()`
128 /// doesn’t seem to be happy to infer that it should go with the default value.
129 /// It’s a bit sad, really. Ah well, I guess this approach will do.
130 pub type AnyMap
= Map
<dyn Any
>;
132 impl<A
: ?Sized
+ Downcast
> Default
for Map
<A
> {
134 fn default() -> Map
<A
> {
139 impl<A
: ?Sized
+ Downcast
> Map
<A
> {
140 /// Create an empty collection.
142 pub fn new() -> Map
<A
> {
144 raw
: RawMap
::with_hasher(Default
::default()),
148 /// Creates an empty collection with the given initial capacity.
150 pub fn with_capacity(capacity
: usize) -> Map
<A
> {
152 raw
: RawMap
::with_capacity_and_hasher(capacity
, Default
::default()),
156 /// Returns the number of elements the collection can hold without reallocating.
158 pub fn capacity(&self) -> usize {
162 /// Reserves capacity for at least `additional` more elements to be inserted
163 /// in the collection. The collection may reserve more space to avoid
164 /// frequent reallocations.
168 /// Panics if the new allocation size overflows `usize`.
170 pub fn reserve(&mut self, additional
: usize) {
171 self.raw
.reserve(additional
)
174 /// Shrinks the capacity of the collection as much as possible. It will drop
175 /// down as much as possible while maintaining the internal rules
176 /// and possibly leaving some space in accordance with the resize policy.
178 pub fn shrink_to_fit(&mut self) {
179 self.raw
.shrink_to_fit()
182 // Additional stable methods (as of 1.60.0-nightly) that could be added:
183 // try_reserve(&mut self, additional: usize) -> Result<(), TryReserveError> (1.57.0)
184 // shrink_to(&mut self, min_capacity: usize) (1.56.0)
186 /// Returns the number of items in the collection.
188 pub fn len(&self) -> usize {
192 /// Returns true if there are no items in the collection.
194 pub fn is_empty(&self) -> bool
{
198 /// Removes all items from the collection. Keeps the allocated memory for reuse.
200 pub fn clear(&mut self) {
204 /// Returns a reference to the value stored in the collection for the type `T`, if it exists.
206 pub fn get
<T
: IntoBox
<A
>>(&self) -> Option
<&T
> {
207 self.raw
.get(&TypeId
::of
::<T
>())
208 .map(|any
| unsafe { any
.downcast_ref_unchecked
::<T
>() })
211 /// Returns a mutable reference to the value stored in the collection for the type `T`,
214 pub fn get_mut
<T
: IntoBox
<A
>>(&mut self) -> Option
<&mut T
> {
215 self.raw
.get_mut(&TypeId
::of
::<T
>())
216 .map(|any
| unsafe { any
.downcast_mut_unchecked
::<T
>() })
219 /// Sets the value stored in the collection for the type `T`.
220 /// If the collection already had a value of type `T`, that value is returned.
221 /// Otherwise, `None` is returned.
223 pub fn insert
<T
: IntoBox
<A
>>(&mut self, value
: T
) -> Option
<T
> {
224 self.raw
.insert(TypeId
::of
::<T
>(), value
.into_box())
225 .map(|any
| unsafe { *any
.downcast_unchecked
::<T
>() })
228 // rustc 1.60.0-nightly has another method try_insert that would be nice to add when stable.
230 /// Removes the `T` value from the collection,
231 /// returning it if there was one or `None` if there was not.
233 pub fn remove
<T
: IntoBox
<A
>>(&mut self) -> Option
<T
> {
234 self.raw
.remove(&TypeId
::of
::<T
>())
235 .map(|any
| *unsafe { any
.downcast_unchecked
::<T
>() })
238 /// Returns true if the collection contains a value of type `T`.
240 pub fn contains
<T
: IntoBox
<A
>>(&self) -> bool
{
241 self.raw
.contains_key(&TypeId
::of
::<T
>())
244 /// Gets the entry for the given type in the collection for in-place manipulation
246 pub fn entry
<T
: IntoBox
<A
>>(&mut self) -> Entry
<A
, T
> {
247 match self.raw
.entry(TypeId
::of
::<T
>()) {
248 raw_hash_map
::Entry
::Occupied(e
) => Entry
::Occupied(OccupiedEntry
{
252 raw_hash_map
::Entry
::Vacant(e
) => Entry
::Vacant(VacantEntry
{
259 /// Get access to the raw hash map that backs this.
261 /// This will seldom be useful, but it’s conceivable that you could wish to iterate over all
262 /// the items in the collection, and this lets you do that.
264 /// To improve compatibility with Cargo features, interact with this map through the names
265 /// [`anymap::RawMap`][RawMap] and [`anymap::raw_hash_map`][raw_hash_map], rather than through
266 /// `std::collections::{HashMap, hash_map}` or `hashbrown::{HashMap, hash_map}`, for anything
267 /// beyond self methods. Otherwise, if you use std and another crate in the tree enables
268 /// hashbrown, your code will break.
270 pub fn as_raw(&self) -> &RawMap
<A
> {
274 /// Get mutable access to the raw hash map that backs this.
276 /// This will seldom be useful, but it’s conceivable that you could wish to iterate over all
277 /// the items in the collection mutably, or drain or something, or *possibly* even batch
278 /// insert, and this lets you do that.
280 /// To improve compatibility with Cargo features, interact with this map through the names
281 /// [`anymap::RawMap`][RawMap] and [`anymap::raw_hash_map`][raw_hash_map], rather than through
282 /// `std::collections::{HashMap, hash_map}` or `hashbrown::{HashMap, hash_map}`, for anything
283 /// beyond self methods. Otherwise, if you use std and another crate in the tree enables
284 /// hashbrown, your code will break.
288 /// If you insert any values to the raw map, the key (a `TypeId`) must match the value’s type,
289 /// or *undefined behaviour* will occur when you access those values.
291 /// (*Removing* entries is perfectly safe.)
293 pub unsafe fn as_raw_mut(&mut self) -> &mut RawMap
<A
> {
297 /// Convert this into the raw hash map that backs this.
299 /// This will seldom be useful, but it’s conceivable that you could wish to consume all the
300 /// items in the collection and do *something* with some or all of them, and this lets you do
301 /// that, without the `unsafe` that `.as_raw_mut().drain()` would require.
303 /// To improve compatibility with Cargo features, interact with this map through the names
304 /// [`anymap::RawMap`][RawMap] and [`anymap::raw_hash_map`][raw_hash_map], rather than through
305 /// `std::collections::{HashMap, hash_map}` or `hashbrown::{HashMap, hash_map}`, for anything
306 /// beyond self methods. Otherwise, if you use std and another crate in the tree enables
307 /// hashbrown, your code will break.
309 pub fn into_raw(self) -> RawMap
<A
> {
313 /// Construct a map from a collection of raw values.
315 /// You know what? I can’t immediately think of any legitimate use for this, especially because
316 /// of the requirement of the `BuildHasherDefault<TypeIdHasher>` generic in the map.
318 /// Perhaps this will be most practical as `unsafe { Map::from_raw(iter.collect()) }`, iter
319 /// being an iterator over `(TypeId, Box<A>)` pairs. Eh, this method provides symmetry with
320 /// `into_raw`, so I don’t care if literally no one ever uses it. I’m not even going to write a
321 /// test for it, it’s so trivial.
323 /// To improve compatibility with Cargo features, interact with this map through the names
324 /// [`anymap::RawMap`][RawMap] and [`anymap::raw_hash_map`][raw_hash_map], rather than through
325 /// `std::collections::{HashMap, hash_map}` or `hashbrown::{HashMap, hash_map}`, for anything
326 /// beyond self methods. Otherwise, if you use std and another crate in the tree enables
327 /// hashbrown, your code will break.
331 /// For all entries in the raw map, the key (a `TypeId`) must match the value’s type,
332 /// or *undefined behaviour* will occur when you access that entry.
334 pub unsafe fn from_raw(raw
: RawMap
<A
>) -> Map
<A
> {
339 impl<A
: ?Sized
+ Downcast
> Extend
<Box
<A
>> for Map
<A
> {
341 fn extend
<T
: IntoIterator
<Item
= Box
<A
>>>(&mut self, iter
: T
) {
343 let _
= self.raw
.insert(Downcast
::type_id(&*item
), item
);
348 /// A view into a single occupied location in an `Map`.
349 pub struct OccupiedEntry
<'a
, A
: ?Sized
+ Downcast
, V
: 'a
> {
350 #[cfg(all(feature = "std", not(feature = "hashbrown")))]
351 inner
: raw_hash_map
::OccupiedEntry
<'a
, TypeId
, Box
<A
>>,
352 #[cfg(feature = "hashbrown")]
353 inner
: raw_hash_map
::OccupiedEntry
<'a
, TypeId
, Box
<A
>, BuildHasherDefault
<TypeIdHasher
>>,
354 type_
: PhantomData
<V
>,
357 /// A view into a single empty location in an `Map`.
358 pub struct VacantEntry
<'a
, A
: ?Sized
+ Downcast
, V
: 'a
> {
359 #[cfg(all(feature = "std", not(feature = "hashbrown")))]
360 inner
: raw_hash_map
::VacantEntry
<'a
, TypeId
, Box
<A
>>,
361 #[cfg(feature = "hashbrown")]
362 inner
: raw_hash_map
::VacantEntry
<'a
, TypeId
, Box
<A
>, BuildHasherDefault
<TypeIdHasher
>>,
363 type_
: PhantomData
<V
>,
366 /// A view into a single location in an `Map`, which may be vacant or occupied.
367 pub enum Entry
<'a
, A
: ?Sized
+ Downcast
, V
: 'a
> {
368 /// An occupied Entry
369 Occupied(OccupiedEntry
<'a
, A
, V
>),
371 Vacant(VacantEntry
<'a
, A
, V
>),
374 impl<'a
, A
: ?Sized
+ Downcast
, V
: IntoBox
<A
>> Entry
<'a
, A
, V
> {
375 /// Ensures a value is in the entry by inserting the default if empty, and returns
376 /// a mutable reference to the value in the entry.
378 pub fn or_insert(self, default: V
) -> &'a
mut V
{
380 Entry
::Occupied(inner
) => inner
.into_mut(),
381 Entry
::Vacant(inner
) => inner
.insert(default),
385 /// Ensures a value is in the entry by inserting the result of the default function if empty,
386 /// and returns a mutable reference to the value in the entry.
388 pub fn or_insert_with
<F
: FnOnce() -> V
>(self, default: F
) -> &'a
mut V
{
390 Entry
::Occupied(inner
) => inner
.into_mut(),
391 Entry
::Vacant(inner
) => inner
.insert(default()),
395 /// Ensures a value is in the entry by inserting the default value if empty,
396 /// and returns a mutable reference to the value in the entry.
398 pub fn or_default(self) -> &'a
mut V
where V
: Default
{
400 Entry
::Occupied(inner
) => inner
.into_mut(),
401 Entry
::Vacant(inner
) => inner
.insert(Default
::default()),
405 /// Provides in-place mutable access to an occupied entry before any potential inserts into the
408 pub fn and_modify
<F
: FnOnce(&mut V
)>(self, f
: F
) -> Self {
410 Entry
::Occupied(mut inner
) => {
412 Entry
::Occupied(inner
)
414 Entry
::Vacant(inner
) => Entry
::Vacant(inner
),
418 // Additional stable methods (as of 1.60.0-nightly) that could be added:
419 // insert_entry(self, value: V) -> OccupiedEntry<'a, K, V> (1.59.0)
422 impl<'a
, A
: ?Sized
+ Downcast
, V
: IntoBox
<A
>> OccupiedEntry
<'a
, A
, V
> {
423 /// Gets a reference to the value in the entry
425 pub fn get(&self) -> &V
{
426 unsafe { self.inner
.get().downcast_ref_unchecked() }
429 /// Gets a mutable reference to the value in the entry
431 pub fn get_mut(&mut self) -> &mut V
{
432 unsafe { self.inner
.get_mut().downcast_mut_unchecked() }
435 /// Converts the OccupiedEntry into a mutable reference to the value in the entry
436 /// with a lifetime bound to the collection itself
438 pub fn into_mut(self) -> &'a
mut V
{
439 unsafe { self.inner
.into_mut().downcast_mut_unchecked() }
442 /// Sets the value of the entry, and returns the entry's old value
444 pub fn insert(&mut self, value
: V
) -> V
{
445 unsafe { *self.inner
.insert(value
.into_box()).downcast_unchecked() }
448 /// Takes the value out of the entry, and returns it
450 pub fn remove(self) -> V
{
451 unsafe { *self.inner
.remove().downcast_unchecked() }
455 impl<'a
, A
: ?Sized
+ Downcast
, V
: IntoBox
<A
>> VacantEntry
<'a
, A
, V
> {
456 /// Sets the value of the entry with the VacantEntry's key,
457 /// and returns a mutable reference to it
459 pub fn insert(self, value
: V
) -> &'a
mut V
{
460 unsafe { self.inner
.insert(value
.into_box()).downcast_mut_unchecked() }
464 /// A hasher designed to eke a little more speed out, given `TypeId`’s known characteristics.
466 /// Specifically, this is a no-op hasher that expects to be fed a u64’s worth of
467 /// randomly-distributed bits. It works well for `TypeId` (eliminating start-up time, so that my
468 /// get_missing benchmark is ~30ns rather than ~900ns, and being a good deal faster after that, so
469 /// that my insert_and_get_on_260_types benchmark is ~12μs instead of ~21.5μs), but will
470 /// panic in debug mode and always emit zeros in release mode for any other sorts of inputs, so
471 /// yeah, don’t use it! 😀
473 pub struct TypeIdHasher
{
477 impl Hasher
for TypeIdHasher
{
479 fn write(&mut self, bytes
: &[u8]) {
480 // This expects to receive exactly one 64-bit value, and there’s no realistic chance of
481 // that changing, but I don’t want to depend on something that isn’t expressly part of the
482 // contract for safety. But I’m OK with release builds putting everything in one bucket
483 // if it *did* change (and debug builds panicking).
484 debug_assert_eq!(bytes
.len(), 8);
485 let _
= bytes
.try_into()
486 .map(|array
| self.value
= u64::from_ne_bytes(array
));
490 fn finish(&self) -> u64 { self.value
}
497 #[derive(Clone, Debug, PartialEq)] struct A(i32);
498 #[derive(Clone, Debug, PartialEq)] struct B(i32);
499 #[derive(Clone, Debug, PartialEq)] struct C(i32);
500 #[derive(Clone, Debug, PartialEq)] struct D(i32);
501 #[derive(Clone, Debug, PartialEq)] struct E(i32);
502 #[derive(Clone, Debug, PartialEq)] struct F(i32);
503 #[derive(Clone, Debug, PartialEq)] struct J(i32);
505 macro_rules
! test_entry
{
506 ($name
:ident
, $init
:ty
) => {
509 let mut map
= <$init
>::new();
510 assert_eq!(map
.insert(A(10)), None
);
511 assert_eq!(map
.insert(B(20)), None
);
512 assert_eq!(map
.insert(C(30)), None
);
513 assert_eq!(map
.insert(D(40)), None
);
514 assert_eq!(map
.insert(E(50)), None
);
515 assert_eq!(map
.insert(F(60)), None
);
517 // Existing key (insert)
518 match map
.entry
::<A
>() {
519 Entry
::Vacant(_
) => unreachable!(),
520 Entry
::Occupied(mut view
) => {
521 assert_eq!(view
.get(), &A(10));
522 assert_eq!(view
.insert(A(100)), A(10));
525 assert_eq!(map
.get
::<A
>().unwrap(), &A(100));
526 assert_eq!(map
.len(), 6);
529 // Existing key (update)
530 match map
.entry
::<B
>() {
531 Entry
::Vacant(_
) => unreachable!(),
532 Entry
::Occupied(mut view
) => {
533 let v
= view
.get_mut();
534 let new_v
= B(v
.0 * 10);
538 assert_eq!(map
.get
::<B
>().unwrap(), &B(200));
539 assert_eq!(map
.len(), 6);
542 // Existing key (remove)
543 match map
.entry
::<C
>() {
544 Entry
::Vacant(_
) => unreachable!(),
545 Entry
::Occupied(view
) => {
546 assert_eq!(view
.remove(), C(30));
549 assert_eq!(map
.get
::<C
>(), None
);
550 assert_eq!(map
.len(), 5);
553 // Inexistent key (insert)
554 match map
.entry
::<J
>() {
555 Entry
::Occupied(_
) => unreachable!(),
556 Entry
::Vacant(view
) => {
557 assert_eq!(*view
.insert(J(1000)), J(1000));
560 assert_eq!(map
.get
::<J
>().unwrap(), &J(1000));
561 assert_eq!(map
.len(), 6);
563 // Entry.or_insert on existing key
564 map
.entry
::<B
>().or_insert(B(71)).0 += 1;
565 assert_eq!(map
.get
::<B
>().unwrap(), &B(201));
566 assert_eq!(map
.len(), 6);
568 // Entry.or_insert on nonexisting key
569 map
.entry
::<C
>().or_insert(C(300)).0 += 1;
570 assert_eq!(map
.get
::<C
>().unwrap(), &C(301));
571 assert_eq!(map
.len(), 7);
576 test_entry!(test_entry_any
, AnyMap
);
577 test_entry!(test_entry_cloneany
, Map
<dyn CloneAny
>);
581 let map
: AnyMap
= Default
::default();
582 assert_eq!(map
.len(), 0);
587 let mut map
: Map
<dyn CloneAny
> = Map
::new();
588 let _
= map
.insert(A(1));
589 let _
= map
.insert(B(2));
590 let _
= map
.insert(D(3));
591 let _
= map
.insert(E(4));
592 let _
= map
.insert(F(5));
593 let _
= map
.insert(J(6));
594 let map2
= map
.clone();
595 assert_eq!(map2
.len(), 6);
596 assert_eq!(map2
.get
::<A
>(), Some(&A(1)));
597 assert_eq!(map2
.get
::<B
>(), Some(&B(2)));
598 assert_eq!(map2
.get
::<C
>(), None
);
599 assert_eq!(map2
.get
::<D
>(), Some(&D(3)));
600 assert_eq!(map2
.get
::<E
>(), Some(&E(4)));
601 assert_eq!(map2
.get
::<F
>(), Some(&F(5)));
602 assert_eq!(map2
.get
::<J
>(), Some(&J(6)));
606 fn test_varieties() {
607 fn assert_send
<T
: Send
>() { }
608 fn assert_sync
<T
: Sync
>() { }
609 fn assert_clone
<T
: Clone
>() { }
610 fn assert_debug
<T
: ::core
::fmt
::Debug
>() { }
611 assert_send
::<Map
<dyn Any
+ Send
>>();
612 assert_send
::<Map
<dyn Any
+ Send
+ Sync
>>();
613 assert_sync
::<Map
<dyn Any
+ Send
+ Sync
>>();
614 assert_debug
::<Map
<dyn Any
>>();
615 assert_debug
::<Map
<dyn Any
+ Send
>>();
616 assert_debug
::<Map
<dyn Any
+ Send
+ Sync
>>();
617 assert_send
::<Map
<dyn CloneAny
+ Send
>>();
618 assert_send
::<Map
<dyn CloneAny
+ Send
+ Sync
>>();
619 assert_sync
::<Map
<dyn CloneAny
+ Send
+ Sync
>>();
620 assert_clone
::<Map
<dyn CloneAny
+ Send
>>();
621 assert_clone
::<Map
<dyn CloneAny
+ Send
+ Sync
>>();
622 assert_clone
::<Map
<dyn CloneAny
+ Send
+ Sync
>>();
623 assert_debug
::<Map
<dyn CloneAny
>>();
624 assert_debug
::<Map
<dyn CloneAny
+ Send
>>();
625 assert_debug
::<Map
<dyn CloneAny
+ Send
+ Sync
>>();
629 fn type_id_hasher() {
630 #[cfg(not(feature = "std"))]
632 use core
::hash
::Hash
;
633 fn verify_hashing_with(type_id
: TypeId
) {
634 let mut hasher
= TypeIdHasher
::default();
635 type_id
.hash(&mut hasher
);
636 // SAFETY: u64 is valid for all bit patterns.
637 assert_eq!(hasher
.finish(), unsafe { core
::mem
::transmute
::<TypeId
, u64>(type_id
) });
639 // Pick a variety of types, just to demonstrate it’s all sane. Normal, zero-sized, unsized, &c.
640 verify_hashing_with(TypeId
::of
::<usize>());
641 verify_hashing_with(TypeId
::of
::<()>());
642 verify_hashing_with(TypeId
::of
::<str>());
643 verify_hashing_with(TypeId
::of
::<&str>());
644 verify_hashing_with(TypeId
::of
::<Vec
<u8>>());
649 let mut map
= AnyMap
::new();
650 map
.extend([Box
::new(123) as Box
<dyn Any
>, Box
::new(456), Box
::new(true)]);
651 assert_eq!(map
.get(), Some(&456));
652 assert_eq!(map
.get
::<bool
>(), Some(&true));
653 assert!(map
.get
::<Box
<dyn Any
>>().is_none());