<p>The default hashing algorithm is currently <ahref="https://crates.io/crates/ahash"><code>AHash</code></a>, though this is
subject to change at any point in the future. This hash function is very
fast for all types of keys, but this algorithm will typically <em>not</em> protect
against attacks such as HashDoS.</p>
<p>The hashing algorithm can be replaced on a per-<code>HashMap</code> basis using the
<ahref="#method.default"><code>default</code></a>, <ahref="#method.with_hasher"><code>with_hasher</code></a>, and <ahref="#method.with_capacity_and_hasher"><code>with_capacity_and_hasher</code></a> methods. Many
alternative algorithms are available on crates.io, such as the <ahref="https://crates.io/crates/fnv"><code>fnv</code></a> crate.</p>
<p>It is required that the keys implement the <ahref="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> and <ahref="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> traits, although
this can frequently be achieved by using <code>#[derive(PartialEq, Eq, Hash)]</code>.
If you implement these yourself, it is important that the following
<p>In other words, if two keys are equal, their hashes must be equal.</p>
<p>It is a logic error for a key to be modified in such a way that the key’s
hash, as determined by the <ahref="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> trait, or its equality, as determined by
the <ahref="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> trait, changes while it is in the map. This is normally only
possible through <ahref="https://doc.rust-lang.org/std/cell/struct.Cell.html"><code>Cell</code></a>, <ahref="https://doc.rust-lang.org/std/cell/struct.RefCell.html"><code>RefCell</code></a>, global state, I/O, or unsafe code.</p>
<p>It is also a logic error for the <ahref="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> implementation of a key to panic.
This is generally only possible if the trait is implemented manually. If a
panic does occur then the contents of the <code>HashMap</code> may become corrupted and
<spanclass="macro">println!</span>(<spanclass="string">"We've got {} reviews, but Les Misérables ain't one."</span>,
book_reviews.len());
}
<spanclass="comment">// oops, this review has a lot of spelling mistakes, let's delete it.
</span>book_reviews.remove(<spanclass="string">"The Adventures of Sherlock Holmes"</span>);
<spanclass="comment">// Look up the values associated with some keys.
</span><spanclass="kw">let </span>to_find = [<spanclass="string">"Pride and Prejudice"</span>, <spanclass="string">"Alice's Adventure in Wonderland"</span>];
<spanclass="prelude-val">None </span>=><spanclass="macro">println!</span>(<spanclass="string">"{} is unreviewed."</span>, book)
}
}
<spanclass="comment">// Look up the value for a key (will panic if the key is not found).
</span><spanclass="macro">println!</span>(<spanclass="string">"Review for Jane: {}"</span>, book_reviews[<spanclass="string">"Pride and Prejudice"</span>]);
<p>The easiest way to use <code>HashMap</code> with a custom key type is to derive <ahref="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> and <ahref="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a>.
We must also derive <ahref="https://doc.rust-lang.org/std/cmp/trait.PartialEq.html"><code>PartialEq</code></a>.</p>
<spanclass="comment">// use the values stored in map</span></code></pre></div>
</div></details><h2id="implementations"class="section-header">Implementations<ahref="#implementations"class="anchor">§</a></h2><divid="implementations-list"><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-HashMap%3CK,+V,+S%3E"class="impl"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#424-508">source</a><ahref="#impl-HashMap%3CK,+V,+S%3E"class="anchor">§</a><h3class="code-header">impl<K, V, S><aclass="struct"href="struct.HashMap.html"title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.with_hasher"class="method"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#460-465">source</a><h4class="code-header">pub const fn <ahref="#method.with_hasher"class="fn">with_hasher</a>(hash_builder: S) -> Self</h4></section></summary><divclass="docblock"><p>Creates an empty <code>HashMap</code> which will use the given hash builder to hash
keys.</p>
<p>The hash map is initially created with a capacity of 0, so it will not
<p>The <code>hash_builder</code> normally use a fixed key by default and that does
not allow the <code>HashMap</code> to be protected against attacks such as <ahref="https://en.wikipedia.org/wiki/Collision_attack"><code>HashDoS</code></a>.
Users who require HashDoS resistance should explicitly use
[<code>ahash::RandomState</code>] or <ahref="https://doc.rust-lang.org/std/collections/hash_map/struct.RandomState.html"><code>std::collections::hash_map::RandomState</code></a>
as the hasher when creating a <ahref="struct.HashMap.html"title="struct hashbrown::hash_map::HashMap"><code>HashMap</code></a>.</p>
<p>The <code>hash_builder</code> passed should implement the <ahref="https://doc.rust-lang.org/std/hash/trait.BuildHasher.html"><code>BuildHasher</code></a> trait for
the HashMap to be useful, see its documentation for details.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.with_capacity_and_hasher"class="method"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#502-507">source</a><h4class="code-header">pub fn <ahref="#method.with_capacity_and_hasher"class="fn">with_capacity_and_hasher</a>(capacity: <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.usize.html">usize</a>, hash_builder: S) -> Self</h4></section></summary><divclass="docblock"><p>Creates an empty <code>HashMap</code> with the specified capacity, using <code>hash_builder</code>
<p>The <code>hash_builder</code> normally use a fixed key by default and that does
not allow the <code>HashMap</code> to be protected against attacks such as <ahref="https://en.wikipedia.org/wiki/Collision_attack"><code>HashDoS</code></a>.
Users who require HashDoS resistance should explicitly use
[<code>ahash::RandomState</code>] or <ahref="https://doc.rust-lang.org/std/collections/hash_map/struct.RandomState.html"><code>std::collections::hash_map::RandomState</code></a>
as the hasher when creating a <ahref="struct.HashMap.html"title="struct hashbrown::hash_map::HashMap"><code>HashMap</code></a>.</p>
<p>The <code>hash_builder</code> passed should implement the <ahref="https://doc.rust-lang.org/std/hash/trait.BuildHasher.html"><code>BuildHasher</code></a> trait for
the HashMap to be useful, see its documentation for details.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.with_hasher_in"class="method"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#545-550">source</a><h4class="code-header">pub const fn <ahref="#method.with_hasher_in"class="fn">with_hasher_in</a>(hash_builder: S, alloc: A) -> Self</h4></section></summary><divclass="docblock"><p>Creates an empty <code>HashMap</code> which will use the given hash builder to hash
keys. It will be allocated with the given allocator.</p>
<p>The hash map is initially created with a capacity of 0, so it will not allocate until it
<p>The <code>hash_builder</code> normally use a fixed key by default and that does
not allow the <code>HashMap</code> to be protected against attacks such as <ahref="https://en.wikipedia.org/wiki/Collision_attack"><code>HashDoS</code></a>.
Users who require HashDoS resistance should explicitly use
[<code>ahash::RandomState</code>] or <ahref="https://doc.rust-lang.org/std/collections/hash_map/struct.RandomState.html"><code>std::collections::hash_map::RandomState</code></a>
as the hasher when creating a <ahref="struct.HashMap.html"title="struct hashbrown::hash_map::HashMap"><code>HashMap</code></a>.</p>
) -> Self</h4></section></summary><divclass="docblock"><p>Creates an empty <code>HashMap</code> with the specified capacity, using <code>hash_builder</code>
to hash the keys. It will be allocated with the given allocator.</p>
<p>The hash map will be able to hold at least <code>capacity</code> elements without
reallocating. If <code>capacity</code> is 0, the hash map will not allocate.</p>
<p>The <code>hash_builder</code> normally use a fixed key by default and that does
not allow the <code>HashMap</code> to be protected against attacks such as <ahref="https://en.wikipedia.org/wiki/Collision_attack"><code>HashDoS</code></a>.
Users who require HashDoS resistance should explicitly use
[<code>ahash::RandomState</code>] or <ahref="https://doc.rust-lang.org/std/collections/hash_map/struct.RandomState.html"><code>std::collections::hash_map::RandomState</code></a>
as the hasher when creating a <ahref="struct.HashMap.html"title="struct hashbrown::hash_map::HashMap"><code>HashMap</code></a>.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.hasher"class="method"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#602-604">source</a><h4class="code-header">pub fn <ahref="#method.hasher"class="fn">hasher</a>(&self) -><aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&S</a></h4></section></summary><divclass="docblock"><p>Returns a reference to the map’s <ahref="https://doc.rust-lang.org/std/hash/trait.BuildHasher.html"><code>BuildHasher</code></a>.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.capacity"class="method"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#620-622">source</a><h4class="code-header">pub fn <ahref="#method.capacity"class="fn">capacity</a>(&self) -><aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.usize.html">usize</a></h4></section></summary><divclass="docblock"><p>Returns the number of elements the map can hold without reallocating.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.len"class="method"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#830-832">source</a><h4class="code-header">pub fn <ahref="#method.len"class="fn">len</a>(&self) -><aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.usize.html">usize</a></h4></section></summary><divclass="docblock"><p>Returns the number of elements in the map.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.is_empty"class="method"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#847-849">source</a><h4class="code-header">pub fn <ahref="#method.is_empty"class="fn">is_empty</a>(&self) -><aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.bool.html">bool</a></h4></section></summary><divclass="docblock"><p>Returns <code>true</code> if the map contains no elements.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.drain"class="method"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#890-894">source</a><h4class="code-header">pub fn <ahref="#method.drain"class="fn">drain</a>(&mut self) -><aclass="struct"href="struct.Drain.html"title="struct hashbrown::hash_map::Drain">Drain</a><'_, K, V, A><ahref="#"class="tooltip"data-notable-ty="Drain<'_, K, V, A>">ⓘ</a></h4></section></summary><divclass="docblock"><p>Clears the map, returning all key-value pairs as an iterator. Keeps the
allocated memory for reuse.</p>
<p>If the returned iterator is dropped before being fully consumed, it
drops the remaining key-value pairs. The returned iterator keeps a
mutable borrow on the vector to optimize its implementation.</p>
F: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/ops/function/trait.FnMut.html"title="trait core::ops::function::FnMut">FnMut</a>(<aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&K</a>, <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&mut V</a>) -><aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.bool.html">bool</a>,</div></h4></section></summary><divclass="docblock"><p>Retains only the elements specified by the predicate. Keeps the
F: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/ops/function/trait.FnMut.html"title="trait core::ops::function::FnMut">FnMut</a>(<aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&K</a>, <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&mut V</a>) -><aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.bool.html">bool</a>,</div></h4></section></summary><divclass="docblock"><p>Drains elements which are true under the given predicate,
and returns an iterator over the removed items.</p>
<p>In other words, move all pairs <code>(k, v)</code> such that <code>f(&k, &mut v)</code> returns <code>true</code> out
into another iterator.</p>
<p>Note that <code>extract_if</code> lets you mutate every value in the filter closure, regardless of
whether you choose to keep or remove it.</p>
<p>If the returned <code>ExtractIf</code> is not exhausted, e.g. because it is dropped without iterating
or the iteration short-circuits, then the remaining elements will be retained.
Use <ahref="struct.HashMap.html#method.retain"title="method hashbrown::hash_map::HashMap::retain"><code>retain()</code></a> with a negated predicate if you do not need the returned iterator.</p>
A: Allocator,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.reserve"class="method"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#1105-1108">source</a><h4class="code-header">pub fn <ahref="#method.reserve"class="fn">reserve</a>(&mut self, additional: <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.usize.html">usize</a>)</h4></section></summary><divclass="docblock"><p>Reserves capacity for at least <code>additional</code> more elements to be inserted
<p>Panics if the new capacity exceeds <ahref="https://doc.rust-lang.org/std/primitive.isize.html"><code>isize::MAX</code></a> bytes and <ahref="https://doc.rust-lang.org/alloc/alloc/fn.handle_alloc_error.html"><code>abort</code></a> the program
in case of allocation error. Use <ahref="struct.HashMap.html#method.try_reserve"title="method hashbrown::hash_map::HashMap::try_reserve"><code>try_reserve</code></a> instead
if you want to handle memory allocation failure.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.try_reserve"class="method"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#1155-1158">source</a><h4class="code-header">pub fn <ahref="#method.try_reserve"class="fn">try_reserve</a>(&mut self, additional: <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.usize.html">usize</a>) -><aclass="enum"href="https://doc.rust-lang.org/1.80.0/core/result/enum.Result.html"title="enum core::result::Result">Result</a><<aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.unit.html">()</a>, <aclass="enum"href="../enum.TryReserveError.html"title="enum hashbrown::TryReserveError">TryReserveError</a>></h4></section></summary><divclass="docblock"><p>Tries to reserve capacity for at least <code>additional</code> more elements to be inserted
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.shrink_to_fit"class="method"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#1177-1180">source</a><h4class="code-header">pub fn <ahref="#method.shrink_to_fit"class="fn">shrink_to_fit</a>(&mut self)</h4></section></summary><divclass="docblock"><p>Shrinks the capacity of the map 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.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.shrink_to"class="method"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#1206-1209">source</a><h4class="code-header">pub fn <ahref="#method.shrink_to"class="fn">shrink_to</a>(&mut self, min_capacity: <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.usize.html">usize</a>)</h4></section></summary><divclass="docblock"><p>Shrinks the capacity of the map with a lower limit. It will drop
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.entry"class="method"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#1231-1247">source</a><h4class="code-header">pub fn <ahref="#method.entry"class="fn">entry</a>(&mut self, key: K) -><aclass="enum"href="enum.Entry.html"title="enum hashbrown::hash_map::Entry">Entry</a><'_, K, V, S, A></h4></section></summary><divclass="docblock"><p>Gets the given key’s corresponding entry in the map for in-place manipulation.</p>
Q: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/hash/trait.Hash.html"title="trait core::hash::Hash">Hash</a> + <aclass="trait"href="../trait.Equivalent.html"title="trait hashbrown::Equivalent">Equivalent</a><K> + ?<aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html"title="trait core::marker::Sized">Sized</a>,</div></h4></section></summary><divclass="docblock"><p>Gets the given key’s corresponding entry by reference in the map for in-place manipulation.</p>
Q: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/hash/trait.Hash.html"title="trait core::hash::Hash">Hash</a> + <aclass="trait"href="../trait.Equivalent.html"title="trait hashbrown::Equivalent">Equivalent</a><K> + ?<aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html"title="trait core::marker::Sized">Sized</a>,</div></h4></section></summary><divclass="docblock"><p>Returns a reference to the value corresponding to the key.</p>
<p>The key may be any borrowed form of the map’s key type, but
<ahref="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> and <ahref="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> on the borrowed form <em>must</em> match those for
<p>The supplied key may be any borrowed form of the map’s key type, but
<ahref="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> and <ahref="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> on the borrowed form <em>must</em> match those for
Q: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/hash/trait.Hash.html"title="trait core::hash::Hash">Hash</a> + <aclass="trait"href="../trait.Equivalent.html"title="trait hashbrown::Equivalent">Equivalent</a><K> + ?<aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html"title="trait core::marker::Sized">Sized</a>,</div></h4></section></summary><divclass="docblock"><p>Returns the key-value pair corresponding to the supplied key, with a mutable reference to value.</p>
<p>The supplied key may be any borrowed form of the map’s key type, but
<ahref="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> and <ahref="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> on the borrowed form <em>must</em> match those for
Q: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/hash/trait.Hash.html"title="trait core::hash::Hash">Hash</a> + <aclass="trait"href="../trait.Equivalent.html"title="trait hashbrown::Equivalent">Equivalent</a><K> + ?<aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html"title="trait core::marker::Sized">Sized</a>,</div></h4></section></summary><divclass="docblock"><p>Returns <code>true</code> if the map contains a value for the specified key.</p>
<p>The key may be any borrowed form of the map’s key type, but
<ahref="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> and <ahref="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> on the borrowed form <em>must</em> match those for
Q: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/hash/trait.Hash.html"title="trait core::hash::Hash">Hash</a> + <aclass="trait"href="../trait.Equivalent.html"title="trait hashbrown::Equivalent">Equivalent</a><K> + ?<aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html"title="trait core::marker::Sized">Sized</a>,</div></h4></section></summary><divclass="docblock"><p>Returns a mutable reference to the value corresponding to the key.</p>
<p>The key may be any borrowed form of the map’s key type, but
<ahref="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> and <ahref="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> on the borrowed form <em>must</em> match those for
Q: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/hash/trait.Hash.html"title="trait core::hash::Hash">Hash</a> + <aclass="trait"href="../trait.Equivalent.html"title="trait hashbrown::Equivalent">Equivalent</a><K> + ?<aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html"title="trait core::marker::Sized">Sized</a>,</div></h4></section></summary><divclass="docblock"><p>Attempts to get mutable references to <code>N</code> values in the map at once.</p>
Q: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/hash/trait.Hash.html"title="trait core::hash::Hash">Hash</a> + <aclass="trait"href="../trait.Equivalent.html"title="trait hashbrown::Equivalent">Equivalent</a><K> + ?<aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html"title="trait core::marker::Sized">Sized</a>,</div></h4></section></summary><divclass="docblock"><p>Attempts to get mutable references to <code>N</code> values in the map at once, without validating that
<p>Returns an array of length <code>N</code> with the results of each query. <code>None</code> will be returned if
any of the keys are missing.</p>
<p>For a safe alternative see <ahref="struct.HashMap.html#method.get_many_mut"title="method hashbrown::hash_map::HashMap::get_many_mut"><code>get_many_mut</code></a>.</p>
<p>Calling this method with overlapping keys is <em><ahref="https://doc.rust-lang.org/reference/behavior-considered-undefined.html">undefined behavior</a></em> even if the resulting
Q: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/hash/trait.Hash.html"title="trait core::hash::Hash">Hash</a> + <aclass="trait"href="../trait.Equivalent.html"title="trait hashbrown::Equivalent">Equivalent</a><K> + ?<aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html"title="trait core::marker::Sized">Sized</a>,</div></h4></section></summary><divclass="docblock"><p>Attempts to get mutable references to <code>N</code> values in the map at once, with immutable
Q: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/hash/trait.Hash.html"title="trait core::hash::Hash">Hash</a> + <aclass="trait"href="../trait.Equivalent.html"title="trait hashbrown::Equivalent">Equivalent</a><K> + ?<aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html"title="trait core::marker::Sized">Sized</a>,</div></h4></section></summary><divclass="docblock"><p>Attempts to get mutable references to <code>N</code> values in the map at once, with immutable
references to the corresponding keys, without validating that the values are unique.</p>
<p>Returns an array of length <code>N</code> with the results of each query. <code>None</code> will be returned if
any of the keys are missing.</p>
<p>For a safe alternative see <ahref="struct.HashMap.html#method.get_many_key_value_mut"title="method hashbrown::hash_map::HashMap::get_many_key_value_mut"><code>get_many_key_value_mut</code></a>.</p>
<p>Calling this method with overlapping keys is <em><ahref="https://doc.rust-lang.org/reference/behavior-considered-undefined.html">undefined behavior</a></em> even if the resulting
<p>If the map did not have this key present, <ahref="https://doc.rust-lang.org/std/option/enum.Option.html#variant.None"><code>None</code></a> is returned.</p>
<p>If the map did have this key present, the value is updated, and the old
value is returned. The key is not updated, though; this matters for
types that can be <code>==</code> without being identical. See the <ahref="https://doc.rust-lang.org/std/collections/index.html"><code>std::collections</code></a>
<ahref="https://doc.rust-lang.org/std/collections/index.html#insert-and-complex-keys">module-level documentation</a> for more.</p>
) -><aclass="enum"href="https://doc.rust-lang.org/1.80.0/core/result/enum.Result.html"title="enum core::result::Result">Result</a><<aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&mut V</a>, <aclass="struct"href="struct.OccupiedError.html"title="struct hashbrown::hash_map::OccupiedError">OccupiedError</a><'_, K, V, S, A>></h4></section></summary><divclass="docblock"><p>Tries to insert a key-value pair into the map, and returns
Q: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/hash/trait.Hash.html"title="trait core::hash::Hash">Hash</a> + <aclass="trait"href="../trait.Equivalent.html"title="trait hashbrown::Equivalent">Equivalent</a><K> + ?<aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html"title="trait core::marker::Sized">Sized</a>,</div></h4></section></summary><divclass="docblock"><p>Removes a key from the map, returning the value at the key if the key
was previously in the map. Keeps the allocated memory for reuse.</p>
<p>The key may be any borrowed form of the map’s key type, but
<ahref="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> and <ahref="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> on the borrowed form <em>must</em> match those for
Q: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/hash/trait.Hash.html"title="trait core::hash::Hash">Hash</a> + <aclass="trait"href="../trait.Equivalent.html"title="trait hashbrown::Equivalent">Equivalent</a><K> + ?<aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html"title="trait core::marker::Sized">Sized</a>,</div></h4></section></summary><divclass="docblock"><p>Removes a key from the map, returning the stored key and value if the
key was previously in the map. Keeps the allocated memory for reuse.</p>
<p>The key may be any borrowed form of the map’s key type, but
<ahref="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> and <ahref="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> on the borrowed form <em>must</em> match those for
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.raw_entry"class="method"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#2091-2093">source</a><h4class="code-header">pub fn <ahref="#method.raw_entry"class="fn">raw_entry</a>(&self) -><aclass="struct"href="struct.RawEntryBuilder.html"title="struct hashbrown::hash_map::RawEntryBuilder">RawEntryBuilder</a><'_, K, V, S, A></h4></section></summary><divclass="docblock"><p>Creates a raw immutable entry builder for the HashMap.</p>
<p>Raw entries provide the lowest level of control for searching and
manipulating a map. They must be manually initialized with a hash and
then manually searched.</p>
<p>This is useful for</p>
<ul>
<li>Hash memoization</li>
<li>Using a search key that doesn’t work with the Borrow trait</li>
<li>Using custom comparison logic without newtype wrappers</li>
</ul>
<p>Unless you are in such a situation, higher-level and more foolproof APIs like
<code>get</code> should be preferred.</p>
<p>Immutable raw entries have very limited use; you might instead want <code>raw_entry_mut</code>.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.raw_table"class="method"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#2103-2105">source</a><h4class="code-header">pub fn <ahref="#method.raw_table"class="fn">raw_table</a>(&self) ->&<aclass="struct"href="../raw/struct.RawTable.html"title="struct hashbrown::raw::RawTable">RawTable</a><<aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.tuple.html">(K, V)</a>, A></h4></section></summary><divclass="docblock"><p>Returns a reference to the <ahref="../raw/struct.RawTable.html"title="struct hashbrown::raw::RawTable"><code>RawTable</code></a> used underneath <ahref="struct.HashMap.html"title="struct hashbrown::hash_map::HashMap"><code>HashMap</code></a>.
This function is only available if the <code>raw</code> feature of the crate is enabled.</p>
<p>See <ahref="struct.HashMap.html#method.raw_table_mut"title="method hashbrown::hash_map::HashMap::raw_table_mut"><code>raw_table_mut</code></a> for more.</p>
<p>Calling this function is safe, but using the raw hash table API may require
unsafe functions or blocks.</p>
<p><code>RawTable</code> API gives the lowest level of control under the map that can be useful
for extending the HashMap’s API, but may lead to <em><ahref="https://doc.rust-lang.org/reference/behavior-considered-undefined.html">undefined behavior</a></em>.</p>
A: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/default/trait.Default.html"title="trait core::default::Default">Default</a> + Allocator,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.default"class="method trait-impl"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#2227-2229">source</a><ahref="#method.default"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/default/trait.Default.html#tymethod.default"class="fn">default</a>() -> Self</h4></section></summary><divclass="docblock"><p>Creates an empty <code>HashMap<K, V, S, A></code>, with the <code>Default</code> value for the hasher and allocator.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.extend_one-1"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.80.0/src/core/iter/traits/collect.rs.html#453">source</a><ahref="#method.extend_one-1"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.Extend.html#method.extend_one"class="fn">extend_one</a>(&mut self, item: A)</h4></section></summary><spanclass="item-info"><divclass="stab unstable"><spanclass="emoji">🔬</span><span>This is a nightly-only experimental API. (<code>extend_one</code>)</span></div></span><divclass='docblock'>Extends a collection with exactly one element.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.extend_reserve-1"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.80.0/src/core/iter/traits/collect.rs.html#461">source</a><ahref="#method.extend_reserve-1"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.Extend.html#method.extend_reserve"class="fn">extend_reserve</a>(&mut self, additional: <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.usize.html">usize</a>)</h4></section></summary><spanclass="item-info"><divclass="stab unstable"><spanclass="emoji">🔬</span><span>This is a nightly-only experimental API. (<code>extend_one</code>)</span></div></span><divclass='docblock'>Reserves capacity in a collection for the given number of additional elements. <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.Extend.html#method.extend_reserve">Read more</a></div></details></div></details><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-Extend%3C(%26K,+%26V)%3E-for-HashMap%3CK,+V,+S,+A%3E"class="impl"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#6540-6601">source</a><ahref="#impl-Extend%3C(%26K,+%26V)%3E-for-HashMap%3CK,+V,+S,+A%3E"class="anchor">§</a><h3class="code-header">impl<'a, K, V, S, A><aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.Extend.html"title="trait core::iter::traits::collect::Extend">Extend</a><(<aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&'a K</a>, <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&'a V</a>)> for <aclass="struct"href="struct.HashMap.html"title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><divclass="where">where
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.extend_one"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.80.0/src/core/iter/traits/collect.rs.html#453">source</a><ahref="#method.extend_one"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.Extend.html#method.extend_one"class="fn">extend_one</a>(&mut self, item: A)</h4></section></summary><spanclass="item-info"><divclass="stab unstable"><spanclass="emoji">🔬</span><span>This is a nightly-only experimental API. (<code>extend_one</code>)</span></div></span><divclass='docblock'>Extends a collection with exactly one element.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.extend_reserve"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.80.0/src/core/iter/traits/collect.rs.html#461">source</a><ahref="#method.extend_reserve"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.Extend.html#method.extend_reserve"class="fn">extend_reserve</a>(&mut self, additional: <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.usize.html">usize</a>)</h4></section></summary><spanclass="item-info"><divclass="stab unstable"><spanclass="emoji">🔬</span><span>This is a nightly-only experimental API. (<code>extend_one</code>)</span></div></span><divclass='docblock'>Reserves capacity in a collection for the given number of additional elements. <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.Extend.html#method.extend_reserve">Read more</a></div></details></div></details><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-Extend%3C(K,+V)%3E-for-HashMap%3CK,+V,+S,+A%3E"class="impl"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#6457-6536">source</a><ahref="#impl-Extend%3C(K,+V)%3E-for-HashMap%3CK,+V,+S,+A%3E"class="anchor">§</a><h3class="code-header">impl<K, V, S, A><aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.Extend.html"title="trait core::iter::traits::collect::Extend">Extend</a><<aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.tuple.html">(K, V)</a>> for <aclass="struct"href="struct.HashMap.html"title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><divclass="where">where
</div><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.extend-2"class="method trait-impl"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#6499-6514">source</a><ahref="#method.extend-2"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.Extend.html#tymethod.extend"class="fn">extend</a><T: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.IntoIterator.html"title="trait core::iter::traits::collect::IntoIterator">IntoIterator</a><Item = <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.tuple.html">(K, V)</a>>>(&mut self, iter: T)</h4></section></summary><divclass="docblock"><p>Inserts all new key-values from the iterator to existing <code>HashMap<K, V, S, A></code>.
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.extend_one-2"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.80.0/src/core/iter/traits/collect.rs.html#453">source</a><ahref="#method.extend_one-2"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.Extend.html#method.extend_one"class="fn">extend_one</a>(&mut self, item: A)</h4></section></summary><spanclass="item-info"><divclass="stab unstable"><spanclass="emoji">🔬</span><span>This is a nightly-only experimental API. (<code>extend_one</code>)</span></div></span><divclass='docblock'>Extends a collection with exactly one element.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.extend_reserve-2"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.80.0/src/core/iter/traits/collect.rs.html#461">source</a><ahref="#method.extend_reserve-2"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.Extend.html#method.extend_reserve"class="fn">extend_reserve</a>(&mut self, additional: <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.usize.html">usize</a>)</h4></section></summary><spanclass="item-info"><divclass="stab unstable"><spanclass="emoji">🔬</span><span>This is a nightly-only experimental API. (<code>extend_one</code>)</span></div></span><divclass='docblock'>Reserves capacity in a collection for the given number of additional elements. <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.Extend.html#method.extend_reserve">Read more</a></div></details></div></details><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-From%3CHashMap%3CT,+(),+S,+A%3E%3E-for-HashSet%3CT,+S,+A%3E"class="impl"><aclass="src rightside"href="../../src/hashbrown/set.rs.html#1303-1310">source</a><ahref="#impl-From%3CHashMap%3CT,+(),+S,+A%3E%3E-for-HashSet%3CT,+S,+A%3E"class="anchor">§</a><h3class="code-header">impl<T, S, A><aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html"title="trait core::convert::From">From</a><<aclass="struct"href="struct.HashMap.html"title="struct hashbrown::hash_map::HashMap">HashMap</a><T, <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.unit.html">()</a>, S, A>> for <aclass="struct"href="../hash_set/struct.HashSet.html"title="struct hashbrown::hash_set::HashSet">HashSet</a><T, S, A><divclass="where">where
A: Allocator,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.from"class="method trait-impl"><aclass="src rightside"href="../../src/hashbrown/set.rs.html#1307-1309">source</a><ahref="#method.from"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html#tymethod.from"class="fn">from</a>(map: <aclass="struct"href="struct.HashMap.html"title="struct hashbrown::hash_map::HashMap">HashMap</a><T, <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.unit.html">()</a>, S, A>) -> Self</h4></section></summary><divclass='docblock'>Converts to this type from the input type.</div></details></div></details><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-FromIterator%3C(K,+V)%3E-for-HashMap%3CK,+V,+S,+A%3E"class="impl"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#6437-6453">source</a><ahref="#impl-FromIterator%3C(K,+V)%3E-for-HashMap%3CK,+V,+S,+A%3E"class="anchor">§</a><h3class="code-header">impl<K, V, S, A><aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.FromIterator.html"title="trait core::iter::traits::collect::FromIterator">FromIterator</a><<aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.tuple.html">(K, V)</a>> for <aclass="struct"href="struct.HashMap.html"title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><divclass="where">where
A: Allocator,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.index"class="method trait-impl"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#2258-2260">source</a><ahref="#method.index"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/ops/index/trait.Index.html#tymethod.index"class="fn">index</a>(&self, key: <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&Q</a>) -><aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&V</a></h4></section></summary><divclass="docblock"><p>Returns a reference to the value corresponding to the supplied key.</p>
</div></details><detailsclass="toggle"open><summary><sectionid="associatedtype.Output"class="associatedtype trait-impl"><ahref="#associatedtype.Output"class="anchor">§</a><h4class="code-header">type <ahref="https://doc.rust-lang.org/1.80.0/core/ops/index/trait.Index.html#associatedtype.Output"class="associatedtype">Output</a> = V</h4></section></summary><divclass='docblock'>The returned type after indexing.</div></details></div></details><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-IntoIterator-for-%26HashMap%3CK,+V,+S,+A%3E"class="impl"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#4624-4654">source</a><ahref="#impl-IntoIterator-for-%26HashMap%3CK,+V,+S,+A%3E"class="anchor">§</a><h3class="code-header">impl<'a, K, V, S, A: Allocator><aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.IntoIterator.html"title="trait core::iter::traits::collect::IntoIterator">IntoIterator</a> for &'a <aclass="struct"href="struct.HashMap.html"title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.into_iter-2"class="method trait-impl"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#4651-4653">source</a><ahref="#method.into_iter-2"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.IntoIterator.html#tymethod.into_iter"class="fn">into_iter</a>(self) -><aclass="struct"href="struct.Iter.html"title="struct hashbrown::hash_map::Iter">Iter</a><'a, K, V><ahref="#"class="tooltip"data-notable-ty="Iter<'a, K, V>">ⓘ</a></h4></section></summary><divclass="docblock"><p>Creates an iterator over the entries of a <code>HashMap</code> in arbitrary order.
The iterator element type is <code>(&'a K, &'a V)</code>.</p>
<p>Return the same <code>Iter</code> struct as by the <ahref="struct.HashMap.html#method.iter"><code>iter</code></a> method on <ahref="struct.HashMap.html"><code>HashMap</code></a>.</p>
</div></details><detailsclass="toggle"open><summary><sectionid="associatedtype.Item-2"class="associatedtype trait-impl"><ahref="#associatedtype.Item-2"class="anchor">§</a><h4class="code-header">type <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.IntoIterator.html#associatedtype.Item"class="associatedtype">Item</a> = (<aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&'a K</a>, <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&'a V</a>)</h4></section></summary><divclass='docblock'>The type of the elements being iterated over.</div></details><detailsclass="toggle"open><summary><sectionid="associatedtype.IntoIter-2"class="associatedtype trait-impl"><ahref="#associatedtype.IntoIter-2"class="anchor">§</a><h4class="code-header">type <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.IntoIterator.html#associatedtype.IntoIter"class="associatedtype">IntoIter</a> = <aclass="struct"href="struct.Iter.html"title="struct hashbrown::hash_map::Iter">Iter</a><'a, K, V></h4></section></summary><divclass='docblock'>Which kind of iterator are we turning this into?</div></details></div></details><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-IntoIterator-for-%26mut+HashMap%3CK,+V,+S,+A%3E"class="impl"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#4656-4691">source</a><ahref="#impl-IntoIterator-for-%26mut+HashMap%3CK,+V,+S,+A%3E"class="anchor">§</a><h3class="code-header">impl<'a, K, V, S, A: Allocator><aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.IntoIterator.html"title="trait core::iter::traits::collect::IntoIterator">IntoIterator</a> for &'a mut <aclass="struct"href="struct.HashMap.html"title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.into_iter-1"class="method trait-impl"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#4688-4690">source</a><ahref="#method.into_iter-1"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.IntoIterator.html#tymethod.into_iter"class="fn">into_iter</a>(self) -><aclass="struct"href="struct.IterMut.html"title="struct hashbrown::hash_map::IterMut">IterMut</a><'a, K, V><ahref="#"class="tooltip"data-notable-ty="IterMut<'a, K, V>">ⓘ</a></h4></section></summary><divclass="docblock"><p>Creates an iterator over the entries of a <code>HashMap</code> in arbitrary order
</div></details><detailsclass="toggle"open><summary><sectionid="associatedtype.Item-1"class="associatedtype trait-impl"><ahref="#associatedtype.Item-1"class="anchor">§</a><h4class="code-header">type <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.IntoIterator.html#associatedtype.Item"class="associatedtype">Item</a> = (<aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&'a K</a>, <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&'a mut V</a>)</h4></section></summary><divclass='docblock'>The type of the elements being iterated over.</div></details><detailsclass="toggle"open><summary><sectionid="associatedtype.IntoIter-1"class="associatedtype trait-impl"><ahref="#associatedtype.IntoIter-1"class="anchor">§</a><h4class="code-header">type <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.IntoIterator.html#associatedtype.IntoIter"class="associatedtype">IntoIter</a> = <aclass="struct"href="struct.IterMut.html"title="struct hashbrown::hash_map::IterMut">IterMut</a><'a, K, V></h4></section></summary><divclass='docblock'>Which kind of iterator are we turning this into?</div></details></div></details><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-IntoIterator-for-HashMap%3CK,+V,+S,+A%3E"class="impl"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#4693-4721">source</a><ahref="#impl-IntoIterator-for-HashMap%3CK,+V,+S,+A%3E"class="anchor">§</a><h3class="code-header">impl<K, V, S, A: Allocator><aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.IntoIterator.html"title="trait core::iter::traits::collect::IntoIterator">IntoIterator</a> for <aclass="struct"href="struct.HashMap.html"title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.into_iter"class="method trait-impl"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#4716-4720">source</a><ahref="#method.into_iter"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.IntoIterator.html#tymethod.into_iter"class="fn">into_iter</a>(self) -><aclass="struct"href="struct.IntoIter.html"title="struct hashbrown::hash_map::IntoIter">IntoIter</a><K, V, A><ahref="#"class="tooltip"data-notable-ty="IntoIter<K, V, A>">ⓘ</a></h4></section></summary><divclass="docblock"><p>Creates a consuming iterator, that is, one that moves each key-value
</div></details><detailsclass="toggle"open><summary><sectionid="associatedtype.Item"class="associatedtype trait-impl"><ahref="#associatedtype.Item"class="anchor">§</a><h4class="code-header">type <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.IntoIterator.html#associatedtype.Item"class="associatedtype">Item</a> = <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.tuple.html">(K, V)</a></h4></section></summary><divclass='docblock'>The type of the elements being iterated over.</div></details><detailsclass="toggle"open><summary><sectionid="associatedtype.IntoIter"class="associatedtype trait-impl"><ahref="#associatedtype.IntoIter"class="anchor">§</a><h4class="code-header">type <ahref="https://doc.rust-lang.org/1.80.0/core/iter/traits/collect/trait.IntoIterator.html#associatedtype.IntoIter"class="associatedtype">IntoIter</a> = <aclass="struct"href="struct.IntoIter.html"title="struct hashbrown::hash_map::IntoIter">IntoIter</a><K, V, A></h4></section></summary><divclass='docblock'>Which kind of iterator are we turning this into?</div></details></div></details><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-PartialEq-for-HashMap%3CK,+V,+S,+A%3E"class="impl"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#2169-2184">source</a><ahref="#impl-PartialEq-for-HashMap%3CK,+V,+S,+A%3E"class="anchor">§</a><h3class="code-header">impl<K, V, S, A><aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/cmp/trait.PartialEq.html"title="trait core::cmp::PartialEq">PartialEq</a> for <aclass="struct"href="struct.HashMap.html"title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><divclass="where">where
A: Allocator,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.eq"class="method trait-impl"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#2176-2183">source</a><ahref="#method.eq"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/cmp/trait.PartialEq.html#tymethod.eq"class="fn">eq</a>(&self, other: <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&Self</a>) -><aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.bool.html">bool</a></h4></section></summary><divclass='docblock'>This method tests for <code>self</code> and <code>other</code> values to be equal, and is used
by <code>==</code>.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.ne"class="method trait-impl"><spanclass="rightside"><spanclass="since"title="Stable since Rust version 1.0.0">1.0.0</span> · <aclass="src"href="https://doc.rust-lang.org/1.80.0/src/core/cmp.rs.html#263">source</a></span><ahref="#method.ne"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/cmp/trait.PartialEq.html#method.ne"class="fn">ne</a>(&self, other: <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&Rhs</a>) -><aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.bool.html">bool</a></h4></section></summary><divclass='docblock'>This method tests for <code>!=</code>. The default implementation is almost always
sufficient, and should not be overridden without very good reason.</div></details></div></details><sectionid="impl-Eq-for-HashMap%3CK,+V,+S,+A%3E"class="impl"><aclass="src rightside"href="../../src/hashbrown/map.rs.html#2186-2193">source</a><ahref="#impl-Eq-for-HashMap%3CK,+V,+S,+A%3E"class="anchor">§</a><h3class="code-header">impl<K, V, S, A><aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/cmp/trait.Eq.html"title="trait core::cmp::Eq">Eq</a> for <aclass="struct"href="struct.HashMap.html"title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><divclass="where">where
K: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/borrow/trait.Borrow.html"title="trait core::borrow::Borrow">Borrow</a><Q> + ?<aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html"title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.equivalent"class="method trait-impl"><aclass="src rightside"href="../../src/hashbrown/lib.rs.html#171-173">source</a><ahref="#method.equivalent"class="anchor">§</a><h4class="code-header">fn <ahref="../trait.Equivalent.html#tymethod.equivalent"class="fn">equivalent</a>(&self, key: <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&K</a>) -><aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.bool.html">bool</a></h4></section></summary><divclass='docblock'>Checks if this value is equivalent to the given key. <ahref="../trait.Equivalent.html#tymethod.equivalent">Read more</a></div></details></div></details><detailsclass="toggle implementors-toggle"><summary><sectionid="impl-From%3CT%3E-for-T"class="impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#765">source</a><ahref="#impl-From%3CT%3E-for-T"class="anchor">§</a><h3class="code-header">impl<T><aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html"title="trait core::convert::From">From</a><T> for T</h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.from-1"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#768">source</a><ahref="#method.from-1"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html#tymethod.from"class="fn">from</a>(t: T) -> T</h4></section></summary><divclass="docblock"><p>Returns the argument unchanged.</p>
</div></details></div></details><detailsclass="toggle implementors-toggle"><summary><sectionid="impl-Into%3CU%3E-for-T"class="impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#748-750">source</a><ahref="#impl-Into%3CU%3E-for-T"class="anchor">§</a><h3class="code-header">impl<T, U><aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/convert/trait.Into.html"title="trait core::convert::Into">Into</a><U> for T<divclass="where">where
<code><ahref="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html"title="trait core::convert::From">From</a><T> for U</code> chooses to do.</p>
</div></details></div></details><detailsclass="toggle implementors-toggle"><summary><sectionid="impl-ToOwned-for-T"class="impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.80.0/src/alloc/borrow.rs.html#83-85">source</a><ahref="#impl-ToOwned-for-T"class="anchor">§</a><h3class="code-header">impl<T><aclass="trait"href="https://doc.rust-lang.org/1.80.0/alloc/borrow/trait.ToOwned.html"title="trait alloc::borrow::ToOwned">ToOwned</a> for T<divclass="where">where
T: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/clone/trait.Clone.html"title="trait core::clone::Clone">Clone</a>,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle"open><summary><sectionid="associatedtype.Owned"class="associatedtype trait-impl"><ahref="#associatedtype.Owned"class="anchor">§</a><h4class="code-header">type <ahref="https://doc.rust-lang.org/1.80.0/alloc/borrow/trait.ToOwned.html#associatedtype.Owned"class="associatedtype">Owned</a> = T</h4></section></summary><divclass='docblock'>The resulting type after obtaining ownership.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.to_owned"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.80.0/src/alloc/borrow.rs.html#88">source</a><ahref="#method.to_owned"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/alloc/borrow/trait.ToOwned.html#tymethod.to_owned"class="fn">to_owned</a>(&self) -> T</h4></section></summary><divclass='docblock'>Creates owned data from borrowed data, usually by cloning. <ahref="https://doc.rust-lang.org/1.80.0/alloc/borrow/trait.ToOwned.html#tymethod.to_owned">Read more</a></div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.clone_into"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.80.0/src/alloc/borrow.rs.html#92">source</a><ahref="#method.clone_into"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/alloc/borrow/trait.ToOwned.html#method.clone_into"class="fn">clone_into</a>(&self, target: <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&mut T</a>)</h4></section></summary><divclass='docblock'>Uses borrowed data to replace owned data, usually by cloning. <ahref="https://doc.rust-lang.org/1.80.0/alloc/borrow/trait.ToOwned.html#method.clone_into">Read more</a></div></details></div></details><detailsclass="toggle implementors-toggle"><summary><sectionid="impl-TryFrom%3CU%3E-for-T"class="impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#805-807">source</a><ahref="#impl-TryFrom%3CU%3E-for-T"class="anchor">§</a><h3class="code-header">impl<T, U><aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><U> for T<divclass="where">where
U: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/convert/trait.Into.html"title="trait core::convert::Into">Into</a><T>,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle"open><summary><sectionid="associatedtype.Error"class="associatedtype trait-impl"><ahref="#associatedtype.Error"class="anchor">§</a><h4class="code-header">type <ahref="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html#associatedtype.Error"class="associatedtype">Error</a> = <aclass="enum"href="https://doc.rust-lang.org/1.80.0/core/convert/enum.Infallible.html"title="enum core::convert::Infallible">Infallible</a></h4></section></summary><divclass='docblock'>The type returned in the event of a conversion error.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.try_from"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#812">source</a><ahref="#method.try_from"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html#tymethod.try_from"class="fn">try_from</a>(value: U) -><aclass="enum"href="https://doc.rust-lang.org/1.80.0/core/result/enum.Result.html"title="enum core::result::Result">Result</a><T, <T as <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><U>>::<aclass="associatedtype"href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html#associatedtype.Error"title="type core::convert::TryFrom::Error">Error</a>></h4></section></summary><divclass='docblock'>Performs the conversion.</div></details></div></details><detailsclass="toggle implementors-toggle"><summary><sectionid="impl-TryInto%3CU%3E-for-T"class="impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#790-792">source</a><ahref="#impl-TryInto%3CU%3E-for-T"class="anchor">§</a><h3class="code-header">impl<T, U><aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryInto.html"title="trait core::convert::TryInto">TryInto</a><U> for T<divclass="where">where
U: <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><T>,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle"open><summary><sectionid="associatedtype.Error-1"class="associatedtype trait-impl"><ahref="#associatedtype.Error-1"class="anchor">§</a><h4class="code-header">type <ahref="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryInto.html#associatedtype.Error"class="associatedtype">Error</a> = <U as <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><T>>::<aclass="associatedtype"href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html#associatedtype.Error"title="type core::convert::TryFrom::Error">Error</a></h4></section></summary><divclass='docblock'>The type returned in the event of a conversion error.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.try_into"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#797">source</a><ahref="#method.try_into"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryInto.html#tymethod.try_into"class="fn">try_into</a>(self) -><aclass="enum"href="https://doc.rust-lang.org/1.80.0/core/result/enum.Result.html"title="enum core::result::Result">Result</a><U, <U as <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><T>>::<aclass="associatedtype"href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html#associatedtype.Error"title="type core::convert::TryFrom::Error">Error</a>></h4></section></summary><divclass='docblock'>Performs the conversion.</div></details></div></details></div><scripttype="text/json"id="notable-traits-data">{"Drain<'_,K,V,A>":"<h3>Notabletraitsfor<code><aclass=\"struct\"href=\"struct.Drain.html\"title=\"structhashbrown::hash_map::Drain\">Drain</a><'a,K,V,A></code></h3><pre><code><divclass=\"where\">impl<'a,K,V,A:Allocator><aclass=\"trait\"href=\"https://doc.rust-lang.org/1.80.0/core/iter/traits/iterator/trait.Iterator.html\"title=\"traitcore::iter::traits::iterator::Iterator\">Iterator</a>for<aclass=\"struct\"href=\"struct.Drain.html\"title=\"structhashbrown::hash_map::Drain\">Drain</a><'a,K,V,A></div><divclass=\"where\">type<ahref=\"https://doc.rust-lang.org/1.80.0/core/iter/traits/iterator/trait.Iterator.html#associatedtype.Item\"class=\"associatedtype\">Item</a>=<aclass=\"primitive\"href=\"https://doc.rust-lang.org/1.80.0/core/primitive.tuple.html\">(K,V)</a>;</div>","ExtractIf<'_,K,V,F,A>":"<h3>Notabletraitsfor<code><aclass=\"struct\"href=\"struct.ExtractIf.html\"title=\"structhashbrown::hash_map::ExtractIf\">ExtractIf</a><'_,K,V,F,A></code></h3><pre><code><divclass=\"where\">impl<K,V,F,A><aclass=\"trait\"href=\"https://doc.rust-lang.org/1.80.0/core/iter/traits/iterator/trait.Iterator.html\"title=\"traitcore::iter::traits::iterator::Iterator\">Iterator</a>for<aclass=\"struct\"href=\"struct.ExtractIf.html\"title=\"structhashbrown::hash_map::ExtractIf\">ExtractIf</a><'_,K,V,F,A><divclass=\"where\">where\nF:<aclass=\"trait\"href=\"https://doc.rust-lang.org/1.80.0/core/ops/function/trait.FnMut.html\"title=\"traitcore::ops::function::FnMut\">FnMut</a>(<aclass=\"primitive\"href=\"https://doc.rust-lang.org/1.80.0/core/primitive.reference.html\">&K</a>,<aclass=\"primitive\"href=\"https://doc.rust-lang.org/1.80.0/core/primitive.reference.html\">&mutV</a>)-><aclass=\"primitive\"href=\"https://doc.rust-lang.org/1.80.0/core/primitive.bool.html\">bool</a>,\nA:Allocator,</div></div><divclass=\"where\">type<ahref=\"https://doc.rust-lang.org/1.80.0/core/iter/traits/iterator/trait.Iterato
