| <!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="A hash map implemented with quadratic probing and SIMD lookup."><meta name="keywords" content="rust, rustlang, rust-lang, HashMap"><title>HashMap in hashbrown::hash_map - Rust</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin 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class="sidebar-menu-toggle">☰</button><a class="sidebar-logo" href="../../hashbrown/index.html"><div class="logo-container"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></div></a><h2></h2></nav><nav class="sidebar"><a class="sidebar-logo" href="../../hashbrown/index.html"><div class="logo-container"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></div></a><h2 class="location"><a href="#">HashMap</a></h2><div class="sidebar-elems"><section><h3><a href="#implementations">Methods</a></h3><ul class="block"><li><a href="#method.allocator">allocator</a></li><li><a href="#method.capacity">capacity</a></li><li><a href="#method.clear">clear</a></li><li><a href="#method.contains_key">contains_key</a></li><li><a href="#method.drain">drain</a></li><li><a href="#method.drain_filter">drain_filter</a></li><li><a href="#method.entry">entry</a></li><li><a href="#method.entry_ref">entry_ref</a></li><li><a href="#method.get">get</a></li><li><a href="#method.get_key_value">get_key_value</a></li><li><a href="#method.get_key_value_mut">get_key_value_mut</a></li><li><a href="#method.get_many_key_value_mut">get_many_key_value_mut</a></li><li><a href="#method.get_many_key_value_unchecked_mut">get_many_key_value_unchecked_mut</a></li><li><a href="#method.get_many_mut">get_many_mut</a></li><li><a href="#method.get_many_unchecked_mut">get_many_unchecked_mut</a></li><li><a href="#method.get_mut">get_mut</a></li><li><a href="#method.hasher">hasher</a></li><li><a href="#method.insert">insert</a></li><li><a href="#method.insert_unique_unchecked">insert_unique_unchecked</a></li><li><a href="#method.into_keys">into_keys</a></li><li><a href="#method.into_values">into_values</a></li><li><a href="#method.is_empty">is_empty</a></li><li><a href="#method.iter">iter</a></li><li><a href="#method.iter_mut">iter_mut</a></li><li><a href="#method.keys">keys</a></li><li><a href="#method.len">len</a></li><li><a href="#method.raw_entry">raw_entry</a></li><li><a href="#method.raw_entry_mut">raw_entry_mut</a></li><li><a href="#method.raw_table">raw_table</a></li><li><a href="#method.remove">remove</a></li><li><a href="#method.remove_entry">remove_entry</a></li><li><a href="#method.reserve">reserve</a></li><li><a href="#method.retain">retain</a></li><li><a href="#method.shrink_to">shrink_to</a></li><li><a href="#method.shrink_to_fit">shrink_to_fit</a></li><li><a href="#method.try_insert">try_insert</a></li><li><a href="#method.try_reserve">try_reserve</a></li><li><a href="#method.values">values</a></li><li><a href="#method.values_mut">values_mut</a></li><li><a href="#method.with_capacity_and_hasher">with_capacity_and_hasher</a></li><li><a href="#method.with_capacity_and_hasher_in">with_capacity_and_hasher_in</a></li><li><a href="#method.with_hasher">with_hasher</a></li><li><a href="#method.with_hasher_in">with_hasher_in</a></li></ul><h3><a href="#trait-implementations">Trait Implementations</a></h3><ul class="block"><li><a href="#impl-Clone-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">Clone</a></li><li><a href="#impl-Debug-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">Debug</a></li><li><a href="#impl-Default-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">Default</a></li><li><a href="#impl-Eq-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">Eq</a></li><li><a href="#impl-Extend%3C%26%27a%20(K%2C%20V)%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">Extend<&'a (K, V)></a></li><li><a href="#impl-Extend%3C(%26%27a%20K%2C%20%26%27a%20V)%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">Extend<(&'a K, &'a V)></a></li><li><a href="#impl-Extend%3C(K%2C%20V)%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">Extend<(K, V)></a></li><li><a href="#impl-From%3CHashMap%3CT%2C%20()%2C%20S%2C%20A%3E%3E-for-HashSet%3CT%2C%20S%2C%20A%3E">From<HashMap<T, (), S, A>></a></li><li><a href="#impl-FromIterator%3C(K%2C%20V)%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">FromIterator<(K, V)></a></li><li><a href="#impl-Index%3C%26Q%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">Index<&Q></a></li><li><a href="#impl-IntoIterator-for-%26%27a%20HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">IntoIterator</a></li><li><a href="#impl-IntoIterator-for-%26%27a%20mut%20HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">IntoIterator</a></li><li><a href="#impl-IntoIterator-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">IntoIterator</a></li><li><a href="#impl-PartialEq%3CHashMap%3CK%2C%20V%2C%20S%2C%20A%3E%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">PartialEq<HashMap<K, V, S, A>></a></li></ul><h3><a href="#synthetic-implementations">Auto Trait Implementations</a></h3><ul class="block"><li><a href="#impl-RefUnwindSafe-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">RefUnwindSafe</a></li><li><a href="#impl-Send-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">Send</a></li><li><a href="#impl-Sync-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">Sync</a></li><li><a href="#impl-Unpin-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">Unpin</a></li><li><a href="#impl-UnwindSafe-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">UnwindSafe</a></li></ul><h3><a href="#blanket-implementations">Blanket Implementations</a></h3><ul class="block"><li><a href="#impl-Any-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">Any</a></li><li><a href="#impl-Borrow%3CT%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">Borrow<T></a></li><li><a href="#impl-BorrowMut%3CT%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">BorrowMut<T></a></li><li><a href="#impl-From%3CT%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">From<T></a></li><li><a href="#impl-Into%3CU%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">Into<U></a></li><li><a href="#impl-ToOwned-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">ToOwned</a></li><li><a href="#impl-TryFrom%3CU%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">TryFrom<U></a></li><li><a href="#impl-TryInto%3CU%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E">TryInto<U></a></li></ul></section><h2><a href="index.html">In hashbrown::hash_map</a></h2></div></nav><main><div class="width-limiter"><nav class="sub"><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../wheel.svg"></a></div></div></form></nav><section id="main-content" class="content"><div class="main-heading"><h1 class="fqn">Struct <a href="../index.html">hashbrown</a>::<wbr><a href="index.html">hash_map</a>::<wbr><a class="struct" href="#">HashMap</a><button id="copy-path" onclick="copy_path(this)" title="Copy item path to clipboard"><img src="../../clipboard.svg" width="19" height="18" alt="Copy item path"></button></h1><span class="out-of-band"><a class="srclink" href="../../src/hashbrown/map.rs.html#188-191">source</a> · <a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">[<span class="inner">−</span>]</a></span></div><div class="item-decl"><pre class="rust struct"><code>pub struct HashMap<K, V, S = <a class="enum" href="enum.DefaultHashBuilder.html" title="enum hashbrown::hash_map::DefaultHashBuilder">DefaultHashBuilder</a>, A: Allocator + Clone = Global> { /* private fields */ }</code></pre></div><details class="rustdoc-toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>A hash map implemented with quadratic probing and SIMD lookup.</p> |
| <p>The default hashing algorithm is currently <a href="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 |
| <a href="#method.default"><code>default</code></a>, <a href="#method.with_hasher"><code>with_hasher</code></a>, and <a href="#method.with_capacity_and_hasher"><code>with_capacity_and_hasher</code></a> methods. Many |
| alternative algorithms are available on crates.io, such as the <a href="https://crates.io/crates/fnv"><code>fnv</code></a> crate.</p> |
| <p>It is required that the keys implement the <a href="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> and <a href="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 |
| property holds:</p> |
| <div class="example-wrap"><pre class="language-text"><code>k1 == k2 -> hash(k1) == hash(k2)</code></pre></div> |
| <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 <a href="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> trait, or its equality, as determined by |
| the <a href="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 <a href="https://doc.rust-lang.org/std/cell/struct.Cell.html"><code>Cell</code></a>, <a href="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 <a href="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 |
| some items may be dropped from the table.</p> |
| <h2 id="examples"><a href="#examples">Examples</a></h2> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="comment">// Type inference lets us omit an explicit type signature (which |
| // would be `HashMap<String, String>` in this example). |
| </span><span class="kw">let </span><span class="kw-2">mut </span>book_reviews = HashMap::new(); |
| |
| <span class="comment">// Review some books. |
| </span>book_reviews.insert( |
| <span class="string">"Adventures of Huckleberry Finn"</span>.to_string(), |
| <span class="string">"My favorite book."</span>.to_string(), |
| ); |
| book_reviews.insert( |
| <span class="string">"Grimms' Fairy Tales"</span>.to_string(), |
| <span class="string">"Masterpiece."</span>.to_string(), |
| ); |
| book_reviews.insert( |
| <span class="string">"Pride and Prejudice"</span>.to_string(), |
| <span class="string">"Very enjoyable."</span>.to_string(), |
| ); |
| book_reviews.insert( |
| <span class="string">"The Adventures of Sherlock Holmes"</span>.to_string(), |
| <span class="string">"Eye lyked it alot."</span>.to_string(), |
| ); |
| |
| <span class="comment">// Check for a specific one. |
| // When collections store owned values (String), they can still be |
| // queried using references (&str). |
| </span><span class="kw">if </span>!book_reviews.contains_key(<span class="string">"Les Misérables"</span>) { |
| <span class="macro">println!</span>(<span class="string">"We've got {} reviews, but Les Misérables ain't one."</span>, |
| book_reviews.len()); |
| } |
| |
| <span class="comment">// oops, this review has a lot of spelling mistakes, let's delete it. |
| </span>book_reviews.remove(<span class="string">"The Adventures of Sherlock Holmes"</span>); |
| |
| <span class="comment">// Look up the values associated with some keys. |
| </span><span class="kw">let </span>to_find = [<span class="string">"Pride and Prejudice"</span>, <span class="string">"Alice's Adventure in Wonderland"</span>]; |
| <span class="kw">for </span><span class="kw-2">&</span>book <span class="kw">in </span><span class="kw-2">&</span>to_find { |
| <span class="kw">match </span>book_reviews.get(book) { |
| <span class="prelude-val">Some</span>(review) => <span class="macro">println!</span>(<span class="string">"{}: {}"</span>, book, review), |
| <span class="prelude-val">None </span>=> <span class="macro">println!</span>(<span class="string">"{} is unreviewed."</span>, book) |
| } |
| } |
| |
| <span class="comment">// Look up the value for a key (will panic if the key is not found). |
| </span><span class="macro">println!</span>(<span class="string">"Review for Jane: {}"</span>, book_reviews[<span class="string">"Pride and Prejudice"</span>]); |
| |
| <span class="comment">// Iterate over everything. |
| </span><span class="kw">for </span>(book, review) <span class="kw">in </span><span class="kw-2">&</span>book_reviews { |
| <span class="macro">println!</span>(<span class="string">"{}: \"{}\""</span>, book, review); |
| }</code></pre></div> |
| <p><code>HashMap</code> also implements an <a href="#method.entry"><code>Entry API</code></a>, which allows |
| for more complex methods of getting, setting, updating and removing keys and |
| their values:</p> |
| |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="comment">// type inference lets us omit an explicit type signature (which |
| // would be `HashMap<&str, u8>` in this example). |
| </span><span class="kw">let </span><span class="kw-2">mut </span>player_stats = HashMap::new(); |
| |
| <span class="kw">fn </span>random_stat_buff() -> u8 { |
| <span class="comment">// could actually return some random value here - let's just return |
| // some fixed value for now |
| </span><span class="number">42 |
| </span>} |
| |
| <span class="comment">// insert a key only if it doesn't already exist |
| </span>player_stats.entry(<span class="string">"health"</span>).or_insert(<span class="number">100</span>); |
| |
| <span class="comment">// insert a key using a function that provides a new value only if it |
| // doesn't already exist |
| </span>player_stats.entry(<span class="string">"defence"</span>).or_insert_with(random_stat_buff); |
| |
| <span class="comment">// update a key, guarding against the key possibly not being set |
| </span><span class="kw">let </span>stat = player_stats.entry(<span class="string">"attack"</span>).or_insert(<span class="number">100</span>); |
| <span class="kw-2">*</span>stat += random_stat_buff();</code></pre></div> |
| <p>The easiest way to use <code>HashMap</code> with a custom key type is to derive <a href="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> and <a href="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a>. |
| We must also derive <a href="https://doc.rust-lang.org/std/cmp/trait.PartialEq.html"><code>PartialEq</code></a>.</p> |
| |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="attribute">#[derive(Hash, Eq, PartialEq, Debug)] |
| </span><span class="kw">struct </span>Viking { |
| name: String, |
| country: String, |
| } |
| |
| <span class="kw">impl </span>Viking { |
| <span class="doccomment">/// Creates a new Viking. |
| </span><span class="kw">fn </span>new(name: <span class="kw-2">&</span>str, country: <span class="kw-2">&</span>str) -> Viking { |
| Viking { name: name.to_string(), country: country.to_string() } |
| } |
| } |
| |
| <span class="comment">// Use a HashMap to store the vikings' health points. |
| </span><span class="kw">let </span><span class="kw-2">mut </span>vikings = HashMap::new(); |
| |
| vikings.insert(Viking::new(<span class="string">"Einar"</span>, <span class="string">"Norway"</span>), <span class="number">25</span>); |
| vikings.insert(Viking::new(<span class="string">"Olaf"</span>, <span class="string">"Denmark"</span>), <span class="number">24</span>); |
| vikings.insert(Viking::new(<span class="string">"Harald"</span>, <span class="string">"Iceland"</span>), <span class="number">12</span>); |
| |
| <span class="comment">// Use derived implementation to print the status of the vikings. |
| </span><span class="kw">for </span>(viking, health) <span class="kw">in </span><span class="kw-2">&</span>vikings { |
| <span class="macro">println!</span>(<span class="string">"{:?} has {} hp"</span>, viking, health); |
| }</code></pre></div> |
| <p>A <code>HashMap</code> with fixed list of elements can be initialized from an array:</p> |
| |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span>timber_resources: HashMap<<span class="kw-2">&</span>str, i32> = [(<span class="string">"Norway"</span>, <span class="number">100</span>), (<span class="string">"Denmark"</span>, <span class="number">50</span>), (<span class="string">"Iceland"</span>, <span class="number">10</span>)] |
| .iter().cloned().collect(); |
| <span class="comment">// use the values stored in map</span></code></pre></div> |
| </div></details><h2 id="implementations" class="small-section-header">Implementations<a href="#implementations" class="anchor"></a></h2><div id="implementations-list"><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-HashMap%3CK%2C%20V%2C%20S%3E" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#351-425">source</a><a href="#impl-HashMap%3CK%2C%20V%2C%20S%3E" class="anchor"></a><h3 class="code-header">impl<K, V, S> <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.with_hasher" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#382-387">source</a><h4 class="code-header">pub const fn <a href="#method.with_hasher" class="fnname">with_hasher</a>(hash_builder: S) -> Self</h4></section></summary><div class="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 |
| allocate until it is first inserted into.</p> |
| <p>Warning: <code>hash_builder</code> is normally randomly generated, and |
| is designed to allow HashMaps to be resistant to attacks that |
| cause many collisions and very poor performance. Setting it |
| manually using this function can expose a DoS attack vector.</p> |
| <p>The <code>hash_builder</code> passed should implement the <a href="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> |
| <h5 id="examples-1"><a href="#examples-1">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| <span class="kw">use </span>hashbrown::hash_map::DefaultHashBuilder; |
| |
| <span class="kw">let </span>s = DefaultHashBuilder::default(); |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::with_hasher(s); |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">0</span>); |
| <span class="macro">assert_eq!</span>(map.capacity(), <span class="number">0</span>); |
| |
| map.insert(<span class="number">1</span>, <span class="number">2</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.with_capacity_and_hasher" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#419-424">source</a><h4 class="code-header">pub fn <a href="#method.with_capacity_and_hasher" class="fnname">with_capacity_and_hasher</a>(capacity: usize, hash_builder: S) -> Self</h4></section></summary><div class="docblock"><p>Creates an empty <code>HashMap</code> with the specified capacity, using <code>hash_builder</code> |
| to hash the keys.</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>Warning: <code>hash_builder</code> is normally randomly generated, and |
| is designed to allow HashMaps to be resistant to attacks that |
| cause many collisions and very poor performance. Setting it |
| manually using this function can expose a DoS attack vector.</p> |
| <p>The <code>hash_builder</code> passed should implement the <a href="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> |
| <h5 id="examples-2"><a href="#examples-2">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| <span class="kw">use </span>hashbrown::hash_map::DefaultHashBuilder; |
| |
| <span class="kw">let </span>s = DefaultHashBuilder::default(); |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::with_capacity_and_hasher(<span class="number">10</span>, s); |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">0</span>); |
| <span class="macro">assert!</span>(map.capacity() >= <span class="number">10</span>); |
| |
| map.insert(<span class="number">1</span>, <span class="number">2</span>);</code></pre></div> |
| </div></details></div></details><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#427-981">source</a><a href="#impl-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<K, V, S, A: Allocator + Clone> <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.allocator" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#430-432">source</a><h4 class="code-header">pub fn <a href="#method.allocator" class="fnname">allocator</a>(&self) -> &A</h4></section></summary><div class="docblock"><p>Returns a reference to the underlying allocator.</p> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.with_hasher_in" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#455-460">source</a><h4 class="code-header">pub fn <a href="#method.with_hasher_in" class="fnname">with_hasher_in</a>(hash_builder: S, alloc: A) -> Self</h4></section></summary><div class="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 created map has the default initial capacity.</p> |
| <p>Warning: <code>hash_builder</code> is normally randomly generated, and |
| is designed to allow HashMaps to be resistant to attacks that |
| cause many collisions and very poor performance. Setting it |
| manually using this function can expose a DoS attack vector.</p> |
| <h5 id="examples-3"><a href="#examples-3">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| <span class="kw">use </span>hashbrown::hash_map::DefaultHashBuilder; |
| |
| <span class="kw">let </span>s = DefaultHashBuilder::default(); |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::with_hasher(s); |
| map.insert(<span class="number">1</span>, <span class="number">2</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.with_capacity_and_hasher_in" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#484-489">source</a><h4 class="code-header">pub fn <a href="#method.with_capacity_and_hasher_in" class="fnname">with_capacity_and_hasher_in</a>(<br> capacity: usize,<br> hash_builder: S,<br> alloc: A<br>) -> Self</h4></section></summary><div class="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>Warning: <code>hash_builder</code> is normally randomly generated, and |
| is designed to allow HashMaps to be resistant to attacks that |
| cause many collisions and very poor performance. Setting it |
| manually using this function can expose a DoS attack vector.</p> |
| <h5 id="examples-4"><a href="#examples-4">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| <span class="kw">use </span>hashbrown::hash_map::DefaultHashBuilder; |
| |
| <span class="kw">let </span>s = DefaultHashBuilder::default(); |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::with_capacity_and_hasher(<span class="number">10</span>, s); |
| map.insert(<span class="number">1</span>, <span class="number">2</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.hasher" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#506-508">source</a><h4 class="code-header">pub fn <a href="#method.hasher" class="fnname">hasher</a>(&self) -> &S</h4></section></summary><div class="docblock"><p>Returns a reference to the map’s <a href="https://doc.rust-lang.org/std/hash/trait.BuildHasher.html"><code>BuildHasher</code></a>.</p> |
| <h5 id="examples-5"><a href="#examples-5">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| <span class="kw">use </span>hashbrown::hash_map::DefaultHashBuilder; |
| |
| <span class="kw">let </span>hasher = DefaultHashBuilder::default(); |
| <span class="kw">let </span>map: HashMap<i32, i32> = HashMap::with_hasher(hasher); |
| <span class="kw">let </span>hasher: <span class="kw-2">&</span>DefaultHashBuilder = map.hasher();</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.capacity" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#524-526">source</a><h4 class="code-header">pub fn <a href="#method.capacity" class="fnname">capacity</a>(&self) -> usize</h4></section></summary><div class="docblock"><p>Returns the number of elements the map can hold without reallocating.</p> |
| <p>This number is a lower bound; the <code>HashMap<K, V></code> might be able to hold |
| more, but is guaranteed to be able to hold at least this many.</p> |
| <h5 id="examples-6"><a href="#examples-6">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| <span class="kw">let </span>map: HashMap<i32, i32> = HashMap::with_capacity(<span class="number">100</span>); |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">0</span>); |
| <span class="macro">assert!</span>(map.capacity() >= <span class="number">100</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.keys" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#556-558">source</a><h4 class="code-header">pub fn <a href="#method.keys" class="fnname">keys</a>(&self) -> <a class="struct" href="struct.Keys.html" title="struct hashbrown::hash_map::Keys">Keys</a><'_, K, V><span class="notable-traits"><span class="notable-traits-tooltip">ⓘ<span class="notable-traits-tooltiptext"><span class="docblock"><span class="notable">Notable traits for <a class="struct" href="struct.Keys.html" title="struct hashbrown::hash_map::Keys">Keys</a><'a, K, V></span><code class="content"><span class="where fmt-newline">impl<'a, K, V> Iterator for <a class="struct" href="struct.Keys.html" title="struct hashbrown::hash_map::Keys">Keys</a><'a, K, V></span><span class="where fmt-newline"> type <a class="associatedtype">Item</a> = &'a K;</span></code></span></span></span></span></h4></section></summary><div class="docblock"><p>An iterator visiting all keys in arbitrary order. |
| The iterator element type is <code>&'a K</code>.</p> |
| <h5 id="examples-7"><a href="#examples-7">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| map.insert(<span class="string">"a"</span>, <span class="number">1</span>); |
| map.insert(<span class="string">"b"</span>, <span class="number">2</span>); |
| map.insert(<span class="string">"c"</span>, <span class="number">3</span>); |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">3</span>); |
| <span class="kw">let </span><span class="kw-2">mut </span>vec: Vec<<span class="kw-2">&</span>str> = Vec::new(); |
| |
| <span class="kw">for </span>key <span class="kw">in </span>map.keys() { |
| <span class="macro">println!</span>(<span class="string">"{}"</span>, key); |
| vec.push(<span class="kw-2">*</span>key); |
| } |
| |
| <span class="comment">// The `Keys` iterator produces keys in arbitrary order, so the |
| // keys must be sorted to test them against a sorted array. |
| </span>vec.sort_unstable(); |
| <span class="macro">assert_eq!</span>(vec, [<span class="string">"a"</span>, <span class="string">"b"</span>, <span class="string">"c"</span>]); |
| |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">3</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.values" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#588-590">source</a><h4 class="code-header">pub fn <a href="#method.values" class="fnname">values</a>(&self) -> <a class="struct" href="struct.Values.html" title="struct hashbrown::hash_map::Values">Values</a><'_, K, V><span class="notable-traits"><span class="notable-traits-tooltip">ⓘ<span class="notable-traits-tooltiptext"><span class="docblock"><span class="notable">Notable traits for <a class="struct" href="struct.Values.html" title="struct hashbrown::hash_map::Values">Values</a><'a, K, V></span><code class="content"><span class="where fmt-newline">impl<'a, K, V> Iterator for <a class="struct" href="struct.Values.html" title="struct hashbrown::hash_map::Values">Values</a><'a, K, V></span><span class="where fmt-newline"> type <a class="associatedtype">Item</a> = &'a V;</span></code></span></span></span></span></h4></section></summary><div class="docblock"><p>An iterator visiting all values in arbitrary order. |
| The iterator element type is <code>&'a V</code>.</p> |
| <h5 id="examples-8"><a href="#examples-8">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| map.insert(<span class="string">"a"</span>, <span class="number">1</span>); |
| map.insert(<span class="string">"b"</span>, <span class="number">2</span>); |
| map.insert(<span class="string">"c"</span>, <span class="number">3</span>); |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">3</span>); |
| <span class="kw">let </span><span class="kw-2">mut </span>vec: Vec<i32> = Vec::new(); |
| |
| <span class="kw">for </span>val <span class="kw">in </span>map.values() { |
| <span class="macro">println!</span>(<span class="string">"{}"</span>, val); |
| vec.push(<span class="kw-2">*</span>val); |
| } |
| |
| <span class="comment">// The `Values` iterator produces values in arbitrary order, so the |
| // values must be sorted to test them against a sorted array. |
| </span>vec.sort_unstable(); |
| <span class="macro">assert_eq!</span>(vec, [<span class="number">1</span>, <span class="number">2</span>, <span class="number">3</span>]); |
| |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">3</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.values_mut" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#626-630">source</a><h4 class="code-header">pub fn <a href="#method.values_mut" class="fnname">values_mut</a>(&mut self) -> <a class="struct" href="struct.ValuesMut.html" title="struct hashbrown::hash_map::ValuesMut">ValuesMut</a><'_, K, V><span class="notable-traits"><span class="notable-traits-tooltip">ⓘ<span class="notable-traits-tooltiptext"><span class="docblock"><span class="notable">Notable traits for <a class="struct" href="struct.ValuesMut.html" title="struct hashbrown::hash_map::ValuesMut">ValuesMut</a><'a, K, V></span><code class="content"><span class="where fmt-newline">impl<'a, K, V> Iterator for <a class="struct" href="struct.ValuesMut.html" title="struct hashbrown::hash_map::ValuesMut">ValuesMut</a><'a, K, V></span><span class="where fmt-newline"> type <a class="associatedtype">Item</a> = &'a mut V;</span></code></span></span></span></span></h4></section></summary><div class="docblock"><p>An iterator visiting all values mutably in arbitrary order. |
| The iterator element type is <code>&'a mut V</code>.</p> |
| <h5 id="examples-9"><a href="#examples-9">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| |
| map.insert(<span class="string">"a"</span>, <span class="number">1</span>); |
| map.insert(<span class="string">"b"</span>, <span class="number">2</span>); |
| map.insert(<span class="string">"c"</span>, <span class="number">3</span>); |
| |
| <span class="kw">for </span>val <span class="kw">in </span>map.values_mut() { |
| <span class="kw-2">*</span>val = <span class="kw-2">*</span>val + <span class="number">10</span>; |
| } |
| |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">3</span>); |
| <span class="kw">let </span><span class="kw-2">mut </span>vec: Vec<i32> = Vec::new(); |
| |
| <span class="kw">for </span>val <span class="kw">in </span>map.values() { |
| <span class="macro">println!</span>(<span class="string">"{}"</span>, val); |
| vec.push(<span class="kw-2">*</span>val); |
| } |
| |
| <span class="comment">// The `Values` iterator produces values in arbitrary order, so the |
| // values must be sorted to test them against a sorted array. |
| </span>vec.sort_unstable(); |
| <span class="macro">assert_eq!</span>(vec, [<span class="number">11</span>, <span class="number">12</span>, <span class="number">13</span>]); |
| |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">3</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.iter" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#660-668">source</a><h4 class="code-header">pub fn <a href="#method.iter" class="fnname">iter</a>(&self) -> <a class="struct" href="struct.Iter.html" title="struct hashbrown::hash_map::Iter">Iter</a><'_, K, V><span class="notable-traits"><span class="notable-traits-tooltip">ⓘ<span class="notable-traits-tooltiptext"><span class="docblock"><span class="notable">Notable traits for <a class="struct" href="struct.Iter.html" title="struct hashbrown::hash_map::Iter">Iter</a><'a, K, V></span><code class="content"><span class="where fmt-newline">impl<'a, K, V> Iterator for <a class="struct" href="struct.Iter.html" title="struct hashbrown::hash_map::Iter">Iter</a><'a, K, V></span><span class="where fmt-newline"> type <a class="associatedtype">Item</a> = (&'a K, &'a V);</span></code></span></span></span></span></h4></section></summary><div class="docblock"><p>An iterator visiting all key-value pairs in arbitrary order. |
| The iterator element type is <code>(&'a K, &'a V)</code>.</p> |
| <h5 id="examples-10"><a href="#examples-10">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| map.insert(<span class="string">"a"</span>, <span class="number">1</span>); |
| map.insert(<span class="string">"b"</span>, <span class="number">2</span>); |
| map.insert(<span class="string">"c"</span>, <span class="number">3</span>); |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">3</span>); |
| <span class="kw">let </span><span class="kw-2">mut </span>vec: Vec<(<span class="kw-2">&</span>str, i32)> = Vec::new(); |
| |
| <span class="kw">for </span>(key, val) <span class="kw">in </span>map.iter() { |
| <span class="macro">println!</span>(<span class="string">"key: {} val: {}"</span>, key, val); |
| vec.push((<span class="kw-2">*</span>key, <span class="kw-2">*</span>val)); |
| } |
| |
| <span class="comment">// The `Iter` iterator produces items in arbitrary order, so the |
| // items must be sorted to test them against a sorted array. |
| </span>vec.sort_unstable(); |
| <span class="macro">assert_eq!</span>(vec, [(<span class="string">"a"</span>, <span class="number">1</span>), (<span class="string">"b"</span>, <span class="number">2</span>), (<span class="string">"c"</span>, <span class="number">3</span>)]); |
| |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">3</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.iter_mut" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#705-713">source</a><h4 class="code-header">pub fn <a href="#method.iter_mut" class="fnname">iter_mut</a>(&mut self) -> <a class="struct" href="struct.IterMut.html" title="struct hashbrown::hash_map::IterMut">IterMut</a><'_, K, V><span class="notable-traits"><span class="notable-traits-tooltip">ⓘ<span class="notable-traits-tooltiptext"><span class="docblock"><span class="notable">Notable traits for <a class="struct" href="struct.IterMut.html" title="struct hashbrown::hash_map::IterMut">IterMut</a><'a, K, V></span><code class="content"><span class="where fmt-newline">impl<'a, K, V> Iterator for <a class="struct" href="struct.IterMut.html" title="struct hashbrown::hash_map::IterMut">IterMut</a><'a, K, V></span><span class="where fmt-newline"> type <a class="associatedtype">Item</a> = (&'a K, &'a mut V);</span></code></span></span></span></span></h4></section></summary><div class="docblock"><p>An iterator visiting all key-value pairs in arbitrary order, |
| with mutable references to the values. |
| The iterator element type is <code>(&'a K, &'a mut V)</code>.</p> |
| <h5 id="examples-11"><a href="#examples-11">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| map.insert(<span class="string">"a"</span>, <span class="number">1</span>); |
| map.insert(<span class="string">"b"</span>, <span class="number">2</span>); |
| map.insert(<span class="string">"c"</span>, <span class="number">3</span>); |
| |
| <span class="comment">// Update all values |
| </span><span class="kw">for </span>(<span class="kw">_</span>, val) <span class="kw">in </span>map.iter_mut() { |
| <span class="kw-2">*</span>val <span class="kw-2">*</span>= <span class="number">2</span>; |
| } |
| |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">3</span>); |
| <span class="kw">let </span><span class="kw-2">mut </span>vec: Vec<(<span class="kw-2">&</span>str, i32)> = Vec::new(); |
| |
| <span class="kw">for </span>(key, val) <span class="kw">in </span><span class="kw-2">&</span>map { |
| <span class="macro">println!</span>(<span class="string">"key: {} val: {}"</span>, key, val); |
| vec.push((<span class="kw-2">*</span>key, <span class="kw-2">*</span>val)); |
| } |
| |
| <span class="comment">// The `Iter` iterator produces items in arbitrary order, so the |
| // items must be sorted to test them against a sorted array. |
| </span>vec.sort_unstable(); |
| <span class="macro">assert_eq!</span>(vec, [(<span class="string">"a"</span>, <span class="number">2</span>), (<span class="string">"b"</span>, <span class="number">4</span>), (<span class="string">"c"</span>, <span class="number">6</span>)]); |
| |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">3</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.len" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#734-736">source</a><h4 class="code-header">pub fn <a href="#method.len" class="fnname">len</a>(&self) -> usize</h4></section></summary><div class="docblock"><p>Returns the number of elements in the map.</p> |
| <h5 id="examples-12"><a href="#examples-12">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>a = HashMap::new(); |
| <span class="macro">assert_eq!</span>(a.len(), <span class="number">0</span>); |
| a.insert(<span class="number">1</span>, <span class="string">"a"</span>); |
| <span class="macro">assert_eq!</span>(a.len(), <span class="number">1</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.is_empty" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#751-753">source</a><h4 class="code-header">pub fn <a href="#method.is_empty" class="fnname">is_empty</a>(&self) -> bool</h4></section></summary><div class="docblock"><p>Returns <code>true</code> if the map contains no elements.</p> |
| <h5 id="examples-13"><a href="#examples-13">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>a = HashMap::new(); |
| <span class="macro">assert!</span>(a.is_empty()); |
| a.insert(<span class="number">1</span>, <span class="string">"a"</span>); |
| <span class="macro">assert!</span>(!a.is_empty());</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.drain" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#794-798">source</a><h4 class="code-header">pub fn <a href="#method.drain" class="fnname">drain</a>(&mut self) -> <a class="struct" href="struct.Drain.html" title="struct hashbrown::hash_map::Drain">Drain</a><'_, K, V, A><span class="notable-traits"><span class="notable-traits-tooltip">ⓘ<span class="notable-traits-tooltiptext"><span class="docblock"><span class="notable">Notable traits for <a class="struct" href="struct.Drain.html" title="struct hashbrown::hash_map::Drain">Drain</a><'a, K, V, A></span><code class="content"><span class="where fmt-newline">impl<'a, K, V, A: Allocator + Clone> Iterator for <a class="struct" href="struct.Drain.html" title="struct hashbrown::hash_map::Drain">Drain</a><'a, K, V, A></span><span class="where fmt-newline"> type <a class="associatedtype">Item</a> = (K, V);</span></code></span></span></span></span></h4></section></summary><div class="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> |
| <h5 id="examples-14"><a href="#examples-14">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>a = HashMap::new(); |
| a.insert(<span class="number">1</span>, <span class="string">"a"</span>); |
| a.insert(<span class="number">2</span>, <span class="string">"b"</span>); |
| <span class="kw">let </span>capacity_before_drain = a.capacity(); |
| |
| <span class="kw">for </span>(k, v) <span class="kw">in </span>a.drain().take(<span class="number">1</span>) { |
| <span class="macro">assert!</span>(k == <span class="number">1 </span>|| k == <span class="number">2</span>); |
| <span class="macro">assert!</span>(v == <span class="string">"a" </span>|| v == <span class="string">"b"</span>); |
| } |
| |
| <span class="comment">// As we can see, the map is empty and contains no element. |
| </span><span class="macro">assert!</span>(a.is_empty() && a.len() == <span class="number">0</span>); |
| <span class="comment">// But map capacity is equal to old one. |
| </span><span class="macro">assert_eq!</span>(a.capacity(), capacity_before_drain); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>a = HashMap::new(); |
| a.insert(<span class="number">1</span>, <span class="string">"a"</span>); |
| a.insert(<span class="number">2</span>, <span class="string">"b"</span>); |
| |
| { <span class="comment">// Iterator is dropped without being consumed. |
| </span><span class="kw">let </span>d = a.drain(); |
| } |
| |
| <span class="comment">// But the map is empty even if we do not use Drain iterator. |
| </span><span class="macro">assert!</span>(a.is_empty());</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.retain" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#826-839">source</a><h4 class="code-header">pub fn <a href="#method.retain" class="fnname">retain</a><F>(&mut self, f: F)<span class="where fmt-newline">where<br> F: FnMut(&K, &mut V) -> bool,</span></h4></section></summary><div class="docblock"><p>Retains only the elements specified by the predicate. Keeps the |
| allocated memory for reuse.</p> |
| <p>In other words, remove all pairs <code>(k, v)</code> such that <code>f(&k, &mut v)</code> returns <code>false</code>. |
| The elements are visited in unsorted (and unspecified) order.</p> |
| <h5 id="examples-15"><a href="#examples-15">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map: HashMap<i32, i32> = (<span class="number">0</span>..<span class="number">8</span>).map(|x|(x, x<span class="kw-2">*</span><span class="number">10</span>)).collect(); |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">8</span>); |
| <span class="kw">let </span>capacity_before_retain = map.capacity(); |
| |
| map.retain(|<span class="kw-2">&</span>k, <span class="kw">_</span>| k % <span class="number">2 </span>== <span class="number">0</span>); |
| |
| <span class="comment">// We can see, that the number of elements inside map is changed. |
| </span><span class="macro">assert_eq!</span>(map.len(), <span class="number">4</span>); |
| <span class="comment">// But map capacity is equal to old one. |
| </span><span class="macro">assert_eq!</span>(map.capacity(), capacity_before_retain); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>vec: Vec<(i32, i32)> = map.iter().map(|(<span class="kw-2">&</span>k, <span class="kw-2">&</span>v)| (k, v)).collect(); |
| vec.sort_unstable(); |
| <span class="macro">assert_eq!</span>(vec, [(<span class="number">0</span>, <span class="number">0</span>), (<span class="number">2</span>, <span class="number">20</span>), (<span class="number">4</span>, <span class="number">40</span>), (<span class="number">6</span>, <span class="number">60</span>)]);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.drain_filter" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#889-900">source</a><h4 class="code-header">pub fn <a href="#method.drain_filter" class="fnname">drain_filter</a><F>(&mut self, f: F) -> <a class="struct" href="struct.DrainFilter.html" title="struct hashbrown::hash_map::DrainFilter">DrainFilter</a><'_, K, V, F, A><span class="notable-traits"><span class="notable-traits-tooltip">ⓘ<span class="notable-traits-tooltiptext"><span class="docblock"><span class="notable">Notable traits for <a class="struct" href="struct.DrainFilter.html" title="struct hashbrown::hash_map::DrainFilter">DrainFilter</a><'_, K, V, F, A></span><code class="content"><span class="where fmt-newline">impl<K, V, F, A> Iterator for <a class="struct" href="struct.DrainFilter.html" title="struct hashbrown::hash_map::DrainFilter">DrainFilter</a><'_, K, V, F, A><span class="where fmt-newline">where<br> F: FnMut(&K, &mut V) -> bool,<br> A: Allocator + Clone,</span></span><span class="where fmt-newline"> type <a class="associatedtype">Item</a> = (K, V);</span></code></span></span></span></span><span class="where fmt-newline">where<br> F: FnMut(&K, &mut V) -> bool,</span></h4></section></summary><div class="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>drain_filter</code> lets you mutate every value in the filter closure, regardless of |
| whether you choose to keep or remove it.</p> |
| <p>When the returned DrainedFilter is dropped, any remaining elements that satisfy |
| the predicate are dropped from the table.</p> |
| <p>It is unspecified how many more elements will be subjected to the closure |
| if a panic occurs in the closure, or a panic occurs while dropping an element, |
| or if the <code>DrainFilter</code> value is leaked.</p> |
| <p>Keeps the allocated memory for reuse.</p> |
| <h5 id="examples-16"><a href="#examples-16">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map: HashMap<i32, i32> = (<span class="number">0</span>..<span class="number">8</span>).map(|x| (x, x)).collect(); |
| <span class="kw">let </span>capacity_before_drain_filter = map.capacity(); |
| <span class="kw">let </span>drained: HashMap<i32, i32> = map.drain_filter(|k, _v| k % <span class="number">2 </span>== <span class="number">0</span>).collect(); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>evens = drained.keys().cloned().collect::<Vec<<span class="kw">_</span>>>(); |
| <span class="kw">let </span><span class="kw-2">mut </span>odds = map.keys().cloned().collect::<Vec<<span class="kw">_</span>>>(); |
| evens.sort(); |
| odds.sort(); |
| |
| <span class="macro">assert_eq!</span>(evens, <span class="macro">vec!</span>[<span class="number">0</span>, <span class="number">2</span>, <span class="number">4</span>, <span class="number">6</span>]); |
| <span class="macro">assert_eq!</span>(odds, <span class="macro">vec!</span>[<span class="number">1</span>, <span class="number">3</span>, <span class="number">5</span>, <span class="number">7</span>]); |
| <span class="comment">// Map capacity is equal to old one. |
| </span><span class="macro">assert_eq!</span>(map.capacity(), capacity_before_drain_filter); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map: HashMap<i32, i32> = (<span class="number">0</span>..<span class="number">8</span>).map(|x| (x, x)).collect(); |
| |
| { <span class="comment">// Iterator is dropped without being consumed. |
| </span><span class="kw">let </span>d = map.drain_filter(|k, _v| k % <span class="number">2 </span>!= <span class="number">0</span>); |
| } |
| |
| <span class="comment">// But the map lens have been reduced by half |
| // even if we do not use DrainFilter iterator. |
| </span><span class="macro">assert_eq!</span>(map.len(), <span class="number">4</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.clear" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#922-924">source</a><h4 class="code-header">pub fn <a href="#method.clear" class="fnname">clear</a>(&mut self)</h4></section></summary><div class="docblock"><p>Clears the map, removing all key-value pairs. Keeps the allocated memory |
| for reuse.</p> |
| <h5 id="examples-17"><a href="#examples-17">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>a = HashMap::new(); |
| a.insert(<span class="number">1</span>, <span class="string">"a"</span>); |
| <span class="kw">let </span>capacity_before_clear = a.capacity(); |
| |
| a.clear(); |
| |
| <span class="comment">// Map is empty. |
| </span><span class="macro">assert!</span>(a.is_empty()); |
| <span class="comment">// But map capacity is equal to old one. |
| </span><span class="macro">assert_eq!</span>(a.capacity(), capacity_before_clear);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.into_keys" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#948-952">source</a><h4 class="code-header">pub fn <a href="#method.into_keys" class="fnname">into_keys</a>(self) -> <a class="struct" href="struct.IntoKeys.html" title="struct hashbrown::hash_map::IntoKeys">IntoKeys</a><K, V, A><span class="notable-traits"><span class="notable-traits-tooltip">ⓘ<span class="notable-traits-tooltiptext"><span class="docblock"><span class="notable">Notable traits for <a class="struct" href="struct.IntoKeys.html" title="struct hashbrown::hash_map::IntoKeys">IntoKeys</a><K, V, A></span><code class="content"><span class="where fmt-newline">impl<K, V, A: Allocator + Clone> Iterator for <a class="struct" href="struct.IntoKeys.html" title="struct hashbrown::hash_map::IntoKeys">IntoKeys</a><K, V, A></span><span class="where fmt-newline"> type <a class="associatedtype">Item</a> = K;</span></code></span></span></span></span></h4></section></summary><div class="docblock"><p>Creates a consuming iterator visiting all the keys in arbitrary order. |
| The map cannot be used after calling this. |
| The iterator element type is <code>K</code>.</p> |
| <h5 id="examples-18"><a href="#examples-18">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| map.insert(<span class="string">"a"</span>, <span class="number">1</span>); |
| map.insert(<span class="string">"b"</span>, <span class="number">2</span>); |
| map.insert(<span class="string">"c"</span>, <span class="number">3</span>); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>vec: Vec<<span class="kw-2">&</span>str> = map.into_keys().collect(); |
| |
| <span class="comment">// The `IntoKeys` iterator produces keys in arbitrary order, so the |
| // keys must be sorted to test them against a sorted array. |
| </span>vec.sort_unstable(); |
| <span class="macro">assert_eq!</span>(vec, [<span class="string">"a"</span>, <span class="string">"b"</span>, <span class="string">"c"</span>]);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.into_values" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#976-980">source</a><h4 class="code-header">pub fn <a href="#method.into_values" class="fnname">into_values</a>(self) -> <a class="struct" href="struct.IntoValues.html" title="struct hashbrown::hash_map::IntoValues">IntoValues</a><K, V, A><span class="notable-traits"><span class="notable-traits-tooltip">ⓘ<span class="notable-traits-tooltiptext"><span class="docblock"><span class="notable">Notable traits for <a class="struct" href="struct.IntoValues.html" title="struct hashbrown::hash_map::IntoValues">IntoValues</a><K, V, A></span><code class="content"><span class="where fmt-newline">impl<K, V, A: Allocator + Clone> Iterator for <a class="struct" href="struct.IntoValues.html" title="struct hashbrown::hash_map::IntoValues">IntoValues</a><K, V, A></span><span class="where fmt-newline"> type <a class="associatedtype">Item</a> = V;</span></code></span></span></span></span></h4></section></summary><div class="docblock"><p>Creates a consuming iterator visiting all the values in arbitrary order. |
| The map cannot be used after calling this. |
| The iterator element type is <code>V</code>.</p> |
| <h5 id="examples-19"><a href="#examples-19">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| map.insert(<span class="string">"a"</span>, <span class="number">1</span>); |
| map.insert(<span class="string">"b"</span>, <span class="number">2</span>); |
| map.insert(<span class="string">"c"</span>, <span class="number">3</span>); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>vec: Vec<i32> = map.into_values().collect(); |
| |
| <span class="comment">// The `IntoValues` iterator produces values in arbitrary order, so |
| // the values must be sorted to test them against a sorted array. |
| </span>vec.sort_unstable(); |
| <span class="macro">assert_eq!</span>(vec, [<span class="number">1</span>, <span class="number">2</span>, <span class="number">3</span>]);</code></pre></div> |
| </div></details></div></details><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E-1" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#983-1862">source</a><a href="#impl-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E-1" class="anchor"></a><h3 class="code-header">impl<K, V, S, A> <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><span class="where fmt-newline">where<br> K: Eq + Hash,<br> S: BuildHasher,<br> A: Allocator + Clone,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.reserve" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1013-1016">source</a><h4 class="code-header">pub fn <a href="#method.reserve" class="fnname">reserve</a>(&mut self, additional: usize)</h4></section></summary><div class="docblock"><p>Reserves capacity for at least <code>additional</code> more elements to be inserted |
| in the <code>HashMap</code>. The collection may reserve more space to avoid |
| frequent reallocations.</p> |
| <h5 id="panics"><a href="#panics">Panics</a></h5> |
| <p>Panics if the new allocation size overflows <a href="https://doc.rust-lang.org/std/primitive.usize.html"><code>usize</code></a>.</p> |
| <h5 id="examples-20"><a href="#examples-20">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| <span class="kw">let </span><span class="kw-2">mut </span>map: HashMap<<span class="kw-2">&</span>str, i32> = HashMap::new(); |
| <span class="comment">// Map is empty and doesn't allocate memory |
| </span><span class="macro">assert_eq!</span>(map.capacity(), <span class="number">0</span>); |
| |
| map.reserve(<span class="number">10</span>); |
| |
| <span class="comment">// And now map can hold at least 10 elements |
| </span><span class="macro">assert!</span>(map.capacity() >= <span class="number">10</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.try_reserve" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1063-1066">source</a><h4 class="code-header">pub fn <a href="#method.try_reserve" class="fnname">try_reserve</a>(&mut self, additional: usize) -> Result<(), <a class="enum" href="../enum.TryReserveError.html" title="enum hashbrown::TryReserveError">TryReserveError</a>></h4></section></summary><div class="docblock"><p>Tries to reserve capacity for at least <code>additional</code> more elements to be inserted |
| in the given <code>HashMap<K,V></code>. The collection may reserve more space to avoid |
| frequent reallocations.</p> |
| <h5 id="errors"><a href="#errors">Errors</a></h5> |
| <p>If the capacity overflows, or the allocator reports a failure, then an error |
| is returned.</p> |
| <h5 id="examples-21"><a href="#examples-21">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map: HashMap<<span class="kw-2">&</span>str, isize> = HashMap::new(); |
| <span class="comment">// Map is empty and doesn't allocate memory |
| </span><span class="macro">assert_eq!</span>(map.capacity(), <span class="number">0</span>); |
| |
| map.try_reserve(<span class="number">10</span>).expect(<span class="string">"why is the test harness OOMing on 10 bytes?"</span>); |
| |
| <span class="comment">// And now map can hold at least 10 elements |
| </span><span class="macro">assert!</span>(map.capacity() >= <span class="number">10</span>);</code></pre></div> |
| <p>If the capacity overflows, or the allocator reports a failure, then an error |
| is returned:</p> |
| |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| <span class="kw">use </span>hashbrown::TryReserveError; |
| <span class="kw">let </span><span class="kw-2">mut </span>map: HashMap<i32, i32> = HashMap::new(); |
| |
| <span class="kw">match </span>map.try_reserve(usize::MAX) { |
| <span class="prelude-val">Err</span>(error) => <span class="kw">match </span>error { |
| TryReserveError::CapacityOverflow => {} |
| <span class="kw">_ </span>=> <span class="macro">panic!</span>(<span class="string">"TryReserveError::AllocError ?"</span>), |
| }, |
| <span class="kw">_ </span>=> <span class="macro">panic!</span>(), |
| }</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.shrink_to_fit" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1085-1088">source</a><h4 class="code-header">pub fn <a href="#method.shrink_to_fit" class="fnname">shrink_to_fit</a>(&mut self)</h4></section></summary><div class="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> |
| <h5 id="examples-22"><a href="#examples-22">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map: HashMap<i32, i32> = HashMap::with_capacity(<span class="number">100</span>); |
| map.insert(<span class="number">1</span>, <span class="number">2</span>); |
| map.insert(<span class="number">3</span>, <span class="number">4</span>); |
| <span class="macro">assert!</span>(map.capacity() >= <span class="number">100</span>); |
| map.shrink_to_fit(); |
| <span class="macro">assert!</span>(map.capacity() >= <span class="number">2</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.shrink_to" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1114-1117">source</a><h4 class="code-header">pub fn <a href="#method.shrink_to" class="fnname">shrink_to</a>(&mut self, min_capacity: usize)</h4></section></summary><div class="docblock"><p>Shrinks the capacity of the map with a lower limit. It will drop |
| down no lower than the supplied limit while maintaining the internal rules |
| and possibly leaving some space in accordance with the resize policy.</p> |
| <p>This function does nothing if the current capacity is smaller than the |
| supplied minimum capacity.</p> |
| <h5 id="examples-23"><a href="#examples-23">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map: HashMap<i32, i32> = HashMap::with_capacity(<span class="number">100</span>); |
| map.insert(<span class="number">1</span>, <span class="number">2</span>); |
| map.insert(<span class="number">3</span>, <span class="number">4</span>); |
| <span class="macro">assert!</span>(map.capacity() >= <span class="number">100</span>); |
| map.shrink_to(<span class="number">10</span>); |
| <span class="macro">assert!</span>(map.capacity() >= <span class="number">10</span>); |
| map.shrink_to(<span class="number">0</span>); |
| <span class="macro">assert!</span>(map.capacity() >= <span class="number">2</span>); |
| map.shrink_to(<span class="number">10</span>); |
| <span class="macro">assert!</span>(map.capacity() >= <span class="number">2</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.entry" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1139-1155">source</a><h4 class="code-header">pub fn <a href="#method.entry" class="fnname">entry</a>(&mut self, key: K) -> <a class="enum" href="enum.Entry.html" title="enum hashbrown::hash_map::Entry">Entry</a><'_, K, V, S, A></h4></section></summary><div class="docblock"><p>Gets the given key’s corresponding entry in the map for in-place manipulation.</p> |
| <h5 id="examples-24"><a href="#examples-24">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>letters = HashMap::new(); |
| |
| <span class="kw">for </span>ch <span class="kw">in </span><span class="string">"a short treatise on fungi"</span>.chars() { |
| <span class="kw">let </span>counter = letters.entry(ch).or_insert(<span class="number">0</span>); |
| <span class="kw-2">*</span>counter += <span class="number">1</span>; |
| } |
| |
| <span class="macro">assert_eq!</span>(letters[<span class="kw-2">&</span><span class="string">'s'</span>], <span class="number">2</span>); |
| <span class="macro">assert_eq!</span>(letters[<span class="kw-2">&</span><span class="string">'t'</span>], <span class="number">3</span>); |
| <span class="macro">assert_eq!</span>(letters[<span class="kw-2">&</span><span class="string">'u'</span>], <span class="number">1</span>); |
| <span class="macro">assert_eq!</span>(letters.get(<span class="kw-2">&</span><span class="string">'y'</span>), <span class="prelude-val">None</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.entry_ref" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1175-1195">source</a><h4 class="code-header">pub fn <a href="#method.entry_ref" class="fnname">entry_ref</a><'a, 'b, Q: ?Sized>(<br> &'a mut self,<br> key: &'b Q<br>) -> <a class="enum" href="enum.EntryRef.html" title="enum hashbrown::hash_map::EntryRef">EntryRef</a><'a, 'b, K, Q, V, S, A><span class="where fmt-newline">where<br> K: Borrow<Q>,<br> Q: Hash + Eq,</span></h4></section></summary><div class="docblock"><p>Gets the given key’s corresponding entry by reference in the map for in-place manipulation.</p> |
| <h5 id="examples-25"><a href="#examples-25">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>words: HashMap<String, usize> = HashMap::new(); |
| <span class="kw">let </span>source = [<span class="string">"poneyland"</span>, <span class="string">"horseyland"</span>, <span class="string">"poneyland"</span>, <span class="string">"poneyland"</span>]; |
| <span class="kw">for </span>(i, <span class="kw-2">&</span>s) <span class="kw">in </span>source.iter().enumerate() { |
| <span class="kw">let </span>counter = words.entry_ref(s).or_insert(<span class="number">0</span>); |
| <span class="kw-2">*</span>counter += <span class="number">1</span>; |
| } |
| |
| <span class="macro">assert_eq!</span>(words[<span class="string">"poneyland"</span>], <span class="number">3</span>); |
| <span class="macro">assert_eq!</span>(words[<span class="string">"horseyland"</span>], <span class="number">1</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.get" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1217-1227">source</a><h4 class="code-header">pub fn <a href="#method.get" class="fnname">get</a><Q: ?Sized>(&self, k: &Q) -> Option<&V><span class="where fmt-newline">where<br> K: Borrow<Q>,<br> Q: Hash + Eq,</span></h4></section></summary><div class="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 |
| <a href="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> and <a href="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> on the borrowed form <em>must</em> match those for |
| the key type.</p> |
| <h5 id="examples-26"><a href="#examples-26">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| map.insert(<span class="number">1</span>, <span class="string">"a"</span>); |
| <span class="macro">assert_eq!</span>(map.get(<span class="kw-2">&</span><span class="number">1</span>), <span class="prelude-val">Some</span>(<span class="kw-2">&</span><span class="string">"a"</span>)); |
| <span class="macro">assert_eq!</span>(map.get(<span class="kw-2">&</span><span class="number">2</span>), <span class="prelude-val">None</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.get_key_value" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1249-1259">source</a><h4 class="code-header">pub fn <a href="#method.get_key_value" class="fnname">get_key_value</a><Q: ?Sized>(&self, k: &Q) -> Option<(&K, &V)><span class="where fmt-newline">where<br> K: Borrow<Q>,<br> Q: Hash + Eq,</span></h4></section></summary><div class="docblock"><p>Returns the key-value pair corresponding to the supplied key.</p> |
| <p>The supplied key may be any borrowed form of the map’s key type, but |
| <a href="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> and <a href="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> on the borrowed form <em>must</em> match those for |
| the key type.</p> |
| <h5 id="examples-27"><a href="#examples-27">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| map.insert(<span class="number">1</span>, <span class="string">"a"</span>); |
| <span class="macro">assert_eq!</span>(map.get_key_value(<span class="kw-2">&</span><span class="number">1</span>), <span class="prelude-val">Some</span>((<span class="kw-2">&</span><span class="number">1</span>, <span class="kw-2">&</span><span class="string">"a"</span>))); |
| <span class="macro">assert_eq!</span>(map.get_key_value(<span class="kw-2">&</span><span class="number">2</span>), <span class="prelude-val">None</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.get_key_value_mut" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1299-1309">source</a><h4 class="code-header">pub fn <a href="#method.get_key_value_mut" class="fnname">get_key_value_mut</a><Q: ?Sized>(&mut self, k: &Q) -> Option<(&K, &mut V)><span class="where fmt-newline">where<br> K: Borrow<Q>,<br> Q: Hash + Eq,</span></h4></section></summary><div class="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 |
| <a href="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> and <a href="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> on the borrowed form <em>must</em> match those for |
| the key type.</p> |
| <h5 id="examples-28"><a href="#examples-28">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| map.insert(<span class="number">1</span>, <span class="string">"a"</span>); |
| <span class="kw">let </span>(k, v) = map.get_key_value_mut(<span class="kw-2">&</span><span class="number">1</span>).unwrap(); |
| <span class="macro">assert_eq!</span>(k, <span class="kw-2">&</span><span class="number">1</span>); |
| <span class="macro">assert_eq!</span>(v, <span class="kw-2">&mut </span><span class="string">"a"</span>); |
| <span class="kw-2">*</span>v = <span class="string">"b"</span>; |
| <span class="macro">assert_eq!</span>(map.get_key_value_mut(<span class="kw-2">&</span><span class="number">1</span>), <span class="prelude-val">Some</span>((<span class="kw-2">&</span><span class="number">1</span>, <span class="kw-2">&mut </span><span class="string">"b"</span>))); |
| <span class="macro">assert_eq!</span>(map.get_key_value_mut(<span class="kw-2">&</span><span class="number">2</span>), <span class="prelude-val">None</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.contains_key" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1331-1337">source</a><h4 class="code-header">pub fn <a href="#method.contains_key" class="fnname">contains_key</a><Q: ?Sized>(&self, k: &Q) -> bool<span class="where fmt-newline">where<br> K: Borrow<Q>,<br> Q: Hash + Eq,</span></h4></section></summary><div class="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 |
| <a href="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> and <a href="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> on the borrowed form <em>must</em> match those for |
| the key type.</p> |
| <h5 id="examples-29"><a href="#examples-29">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| map.insert(<span class="number">1</span>, <span class="string">"a"</span>); |
| <span class="macro">assert_eq!</span>(map.contains_key(<span class="kw-2">&</span><span class="number">1</span>), <span class="bool-val">true</span>); |
| <span class="macro">assert_eq!</span>(map.contains_key(<span class="kw-2">&</span><span class="number">2</span>), <span class="bool-val">false</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.get_mut" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1363-1373">source</a><h4 class="code-header">pub fn <a href="#method.get_mut" class="fnname">get_mut</a><Q: ?Sized>(&mut self, k: &Q) -> Option<&mut V><span class="where fmt-newline">where<br> K: Borrow<Q>,<br> Q: Hash + Eq,</span></h4></section></summary><div class="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 |
| <a href="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> and <a href="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> on the borrowed form <em>must</em> match those for |
| the key type.</p> |
| <h5 id="examples-30"><a href="#examples-30">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| map.insert(<span class="number">1</span>, <span class="string">"a"</span>); |
| <span class="kw">if let </span><span class="prelude-val">Some</span>(x) = map.get_mut(<span class="kw-2">&</span><span class="number">1</span>) { |
| <span class="kw-2">*</span>x = <span class="string">"b"</span>; |
| } |
| <span class="macro">assert_eq!</span>(map[<span class="kw-2">&</span><span class="number">1</span>], <span class="string">"b"</span>); |
| |
| <span class="macro">assert_eq!</span>(map.get_mut(<span class="kw-2">&</span><span class="number">2</span>), <span class="prelude-val">None</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.get_many_mut" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1432-1438">source</a><h4 class="code-header">pub fn <a href="#method.get_many_mut" class="fnname">get_many_mut</a><Q: ?Sized, const N: usize>(<br> &mut self,<br> ks: [&Q; N]<br>) -> Option<[&mut V; N]><span class="where fmt-newline">where<br> K: Borrow<Q>,<br> Q: Hash + Eq,</span></h4></section></summary><div class="docblock"><p>Attempts to get mutable references to <code>N</code> values in the map at once.</p> |
| <p>Returns an array of length <code>N</code> with the results of each query. For soundness, at most one |
| mutable reference will be returned to any value. <code>None</code> will be returned if any of the |
| keys are duplicates or missing.</p> |
| <h5 id="examples-31"><a href="#examples-31">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>libraries = HashMap::new(); |
| libraries.insert(<span class="string">"Bodleian Library"</span>.to_string(), <span class="number">1602</span>); |
| libraries.insert(<span class="string">"Athenæum"</span>.to_string(), <span class="number">1807</span>); |
| libraries.insert(<span class="string">"Herzogin-Anna-Amalia-Bibliothek"</span>.to_string(), <span class="number">1691</span>); |
| libraries.insert(<span class="string">"Library of Congress"</span>.to_string(), <span class="number">1800</span>); |
| |
| <span class="kw">let </span>got = libraries.get_many_mut([ |
| <span class="string">"Athenæum"</span>, |
| <span class="string">"Library of Congress"</span>, |
| ]); |
| <span class="macro">assert_eq!</span>( |
| got, |
| <span class="prelude-val">Some</span>([ |
| <span class="kw-2">&mut </span><span class="number">1807</span>, |
| <span class="kw-2">&mut </span><span class="number">1800</span>, |
| ]), |
| ); |
| |
| <span class="comment">// Missing keys result in None |
| </span><span class="kw">let </span>got = libraries.get_many_mut([ |
| <span class="string">"Athenæum"</span>, |
| <span class="string">"New York Public Library"</span>, |
| ]); |
| <span class="macro">assert_eq!</span>(got, <span class="prelude-val">None</span>); |
| |
| <span class="comment">// Duplicate keys result in None |
| </span><span class="kw">let </span>got = libraries.get_many_mut([ |
| <span class="string">"Athenæum"</span>, |
| <span class="string">"Athenæum"</span>, |
| ]); |
| <span class="macro">assert_eq!</span>(got, <span class="prelude-val">None</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.get_many_unchecked_mut" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1485-1495">source</a><h4 class="code-header">pub unsafe fn <a href="#method.get_many_unchecked_mut" class="fnname">get_many_unchecked_mut</a><Q: ?Sized, const N: usize>(<br> &mut self,<br> ks: [&Q; N]<br>) -> Option<[&mut V; N]><span class="where fmt-newline">where<br> K: Borrow<Q>,<br> Q: Hash + Eq,</span></h4></section></summary><div class="docblock"><p>Attempts to get mutable references to <code>N</code> values in the map at once, 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 <a href="struct.HashMap.html#method.get_many_mut"><code>get_many_mut</code></a>.</p> |
| <h5 id="safety"><a href="#safety">Safety</a></h5> |
| <p>Calling this method with overlapping keys is <em><a href="https://doc.rust-lang.org/reference/behavior-considered-undefined.html">undefined behavior</a></em> even if the resulting |
| references are not used.</p> |
| <h5 id="examples-32"><a href="#examples-32">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>libraries = HashMap::new(); |
| libraries.insert(<span class="string">"Bodleian Library"</span>.to_string(), <span class="number">1602</span>); |
| libraries.insert(<span class="string">"Athenæum"</span>.to_string(), <span class="number">1807</span>); |
| libraries.insert(<span class="string">"Herzogin-Anna-Amalia-Bibliothek"</span>.to_string(), <span class="number">1691</span>); |
| libraries.insert(<span class="string">"Library of Congress"</span>.to_string(), <span class="number">1800</span>); |
| |
| <span class="kw">let </span>got = libraries.get_many_mut([ |
| <span class="string">"Athenæum"</span>, |
| <span class="string">"Library of Congress"</span>, |
| ]); |
| <span class="macro">assert_eq!</span>( |
| got, |
| <span class="prelude-val">Some</span>([ |
| <span class="kw-2">&mut </span><span class="number">1807</span>, |
| <span class="kw-2">&mut </span><span class="number">1800</span>, |
| ]), |
| ); |
| |
| <span class="comment">// Missing keys result in None |
| </span><span class="kw">let </span>got = libraries.get_many_mut([ |
| <span class="string">"Athenæum"</span>, |
| <span class="string">"New York Public Library"</span>, |
| ]); |
| <span class="macro">assert_eq!</span>(got, <span class="prelude-val">None</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.get_many_key_value_mut" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1541-1551">source</a><h4 class="code-header">pub fn <a href="#method.get_many_key_value_mut" class="fnname">get_many_key_value_mut</a><Q: ?Sized, const N: usize>(<br> &mut self,<br> ks: [&Q; N]<br>) -> Option<[(&K, &mut V); N]><span class="where fmt-newline">where<br> K: Borrow<Q>,<br> Q: Hash + Eq,</span></h4></section></summary><div class="docblock"><p>Attempts to get mutable references to <code>N</code> values in the map at once, with immutable |
| references to the corresponding keys.</p> |
| <p>Returns an array of length <code>N</code> with the results of each query. For soundness, at most one |
| mutable reference will be returned to any value. <code>None</code> will be returned if any of the keys |
| are duplicates or missing.</p> |
| <h5 id="examples-33"><a href="#examples-33">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>libraries = HashMap::new(); |
| libraries.insert(<span class="string">"Bodleian Library"</span>.to_string(), <span class="number">1602</span>); |
| libraries.insert(<span class="string">"Athenæum"</span>.to_string(), <span class="number">1807</span>); |
| libraries.insert(<span class="string">"Herzogin-Anna-Amalia-Bibliothek"</span>.to_string(), <span class="number">1691</span>); |
| libraries.insert(<span class="string">"Library of Congress"</span>.to_string(), <span class="number">1800</span>); |
| |
| <span class="kw">let </span>got = libraries.get_many_key_value_mut([ |
| <span class="string">"Bodleian Library"</span>, |
| <span class="string">"Herzogin-Anna-Amalia-Bibliothek"</span>, |
| ]); |
| <span class="macro">assert_eq!</span>( |
| got, |
| <span class="prelude-val">Some</span>([ |
| (<span class="kw-2">&</span><span class="string">"Bodleian Library"</span>.to_string(), <span class="kw-2">&mut </span><span class="number">1602</span>), |
| (<span class="kw-2">&</span><span class="string">"Herzogin-Anna-Amalia-Bibliothek"</span>.to_string(), <span class="kw-2">&mut </span><span class="number">1691</span>), |
| ]), |
| ); |
| <span class="comment">// Missing keys result in None |
| </span><span class="kw">let </span>got = libraries.get_many_key_value_mut([ |
| <span class="string">"Bodleian Library"</span>, |
| <span class="string">"Gewandhaus"</span>, |
| ]); |
| <span class="macro">assert_eq!</span>(got, <span class="prelude-val">None</span>); |
| |
| <span class="comment">// Duplicate keys result in None |
| </span><span class="kw">let </span>got = libraries.get_many_key_value_mut([ |
| <span class="string">"Bodleian Library"</span>, |
| <span class="string">"Herzogin-Anna-Amalia-Bibliothek"</span>, |
| <span class="string">"Herzogin-Anna-Amalia-Bibliothek"</span>, |
| ]); |
| <span class="macro">assert_eq!</span>(got, <span class="prelude-val">None</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.get_many_key_value_unchecked_mut" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1597-1607">source</a><h4 class="code-header">pub unsafe fn <a href="#method.get_many_key_value_unchecked_mut" class="fnname">get_many_key_value_unchecked_mut</a><Q: ?Sized, const N: usize>(<br> &mut self,<br> ks: [&Q; N]<br>) -> Option<[(&K, &mut V); N]><span class="where fmt-newline">where<br> K: Borrow<Q>,<br> Q: Hash + Eq,</span></h4></section></summary><div class="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 <a href="struct.HashMap.html#method.get_many_key_value_mut"><code>get_many_key_value_mut</code></a>.</p> |
| <h5 id="safety-1"><a href="#safety-1">Safety</a></h5> |
| <p>Calling this method with overlapping keys is <em><a href="https://doc.rust-lang.org/reference/behavior-considered-undefined.html">undefined behavior</a></em> even if the resulting |
| references are not used.</p> |
| <h5 id="examples-34"><a href="#examples-34">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>libraries = HashMap::new(); |
| libraries.insert(<span class="string">"Bodleian Library"</span>.to_string(), <span class="number">1602</span>); |
| libraries.insert(<span class="string">"Athenæum"</span>.to_string(), <span class="number">1807</span>); |
| libraries.insert(<span class="string">"Herzogin-Anna-Amalia-Bibliothek"</span>.to_string(), <span class="number">1691</span>); |
| libraries.insert(<span class="string">"Library of Congress"</span>.to_string(), <span class="number">1800</span>); |
| |
| <span class="kw">let </span>got = libraries.get_many_key_value_mut([ |
| <span class="string">"Bodleian Library"</span>, |
| <span class="string">"Herzogin-Anna-Amalia-Bibliothek"</span>, |
| ]); |
| <span class="macro">assert_eq!</span>( |
| got, |
| <span class="prelude-val">Some</span>([ |
| (<span class="kw-2">&</span><span class="string">"Bodleian Library"</span>.to_string(), <span class="kw-2">&mut </span><span class="number">1602</span>), |
| (<span class="kw-2">&</span><span class="string">"Herzogin-Anna-Amalia-Bibliothek"</span>.to_string(), <span class="kw-2">&mut </span><span class="number">1691</span>), |
| ]), |
| ); |
| <span class="comment">// Missing keys result in None |
| </span><span class="kw">let </span>got = libraries.get_many_key_value_mut([ |
| <span class="string">"Bodleian Library"</span>, |
| <span class="string">"Gewandhaus"</span>, |
| ]); |
| <span class="macro">assert_eq!</span>(got, <span class="prelude-val">None</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.insert" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1674-1683">source</a><h4 class="code-header">pub fn <a href="#method.insert" class="fnname">insert</a>(&mut self, k: K, v: V) -> Option<V></h4></section></summary><div class="docblock"><p>Inserts a key-value pair into the map.</p> |
| <p>If the map did not have this key present, <a href="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 <a href="https://doc.rust-lang.org/std/collections/index.html"><code>std::collections</code></a> |
| <a href="https://doc.rust-lang.org/std/collections/index.html#insert-and-complex-keys">module-level documentation</a> for more.</p> |
| <h5 id="examples-35"><a href="#examples-35">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| <span class="macro">assert_eq!</span>(map.insert(<span class="number">37</span>, <span class="string">"a"</span>), <span class="prelude-val">None</span>); |
| <span class="macro">assert_eq!</span>(map.is_empty(), <span class="bool-val">false</span>); |
| |
| map.insert(<span class="number">37</span>, <span class="string">"b"</span>); |
| <span class="macro">assert_eq!</span>(map.insert(<span class="number">37</span>, <span class="string">"c"</span>), <span class="prelude-val">Some</span>(<span class="string">"b"</span>)); |
| <span class="macro">assert_eq!</span>(map[<span class="kw-2">&</span><span class="number">37</span>], <span class="string">"c"</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.insert_unique_unchecked" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1735-1742">source</a><h4 class="code-header">pub fn <a href="#method.insert_unique_unchecked" class="fnname">insert_unique_unchecked</a>(&mut self, k: K, v: V) -> (&K, &mut V)</h4></section></summary><div class="docblock"><p>Insert a key-value pair into the map without checking |
| if the key already exists in the map.</p> |
| <p>Returns a reference to the key and value just inserted.</p> |
| <p>This operation is safe if a key does not exist in the map.</p> |
| <p>However, if a key exists in the map already, the behavior is unspecified: |
| this operation may panic, loop forever, or any following operation with the map |
| may panic, loop forever or return arbitrary result.</p> |
| <p>That said, this operation (and following operations) are guaranteed to |
| not violate memory safety.</p> |
| <p>This operation is faster than regular insert, because it does not perform |
| lookup before insertion.</p> |
| <p>This operation is useful during initial population of the map. |
| For example, when constructing a map from another map, we know |
| that keys are unique.</p> |
| <h5 id="examples-36"><a href="#examples-36">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map1 = HashMap::new(); |
| <span class="macro">assert_eq!</span>(map1.insert(<span class="number">1</span>, <span class="string">"a"</span>), <span class="prelude-val">None</span>); |
| <span class="macro">assert_eq!</span>(map1.insert(<span class="number">2</span>, <span class="string">"b"</span>), <span class="prelude-val">None</span>); |
| <span class="macro">assert_eq!</span>(map1.insert(<span class="number">3</span>, <span class="string">"c"</span>), <span class="prelude-val">None</span>); |
| <span class="macro">assert_eq!</span>(map1.len(), <span class="number">3</span>); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map2 = HashMap::new(); |
| |
| <span class="kw">for </span>(key, value) <span class="kw">in </span>map1.into_iter() { |
| map2.insert_unique_unchecked(key, value); |
| } |
| |
| <span class="kw">let </span>(key, value) = map2.insert_unique_unchecked(<span class="number">4</span>, <span class="string">"d"</span>); |
| <span class="macro">assert_eq!</span>(key, <span class="kw-2">&</span><span class="number">4</span>); |
| <span class="macro">assert_eq!</span>(value, <span class="kw-2">&mut </span><span class="string">"d"</span>); |
| <span class="kw-2">*</span>value = <span class="string">"e"</span>; |
| |
| <span class="macro">assert_eq!</span>(map2[<span class="kw-2">&</span><span class="number">1</span>], <span class="string">"a"</span>); |
| <span class="macro">assert_eq!</span>(map2[<span class="kw-2">&</span><span class="number">2</span>], <span class="string">"b"</span>); |
| <span class="macro">assert_eq!</span>(map2[<span class="kw-2">&</span><span class="number">3</span>], <span class="string">"c"</span>); |
| <span class="macro">assert_eq!</span>(map2[<span class="kw-2">&</span><span class="number">4</span>], <span class="string">"e"</span>); |
| <span class="macro">assert_eq!</span>(map2.len(), <span class="number">4</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.try_insert" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1773-1782">source</a><h4 class="code-header">pub fn <a href="#method.try_insert" class="fnname">try_insert</a>(<br> &mut self,<br> key: K,<br> value: V<br>) -> Result<&mut V, <a class="struct" href="struct.OccupiedError.html" title="struct hashbrown::hash_map::OccupiedError">OccupiedError</a><'_, K, V, S, A>></h4></section></summary><div class="docblock"><p>Tries to insert a key-value pair into the map, and returns |
| a mutable reference to the value in the entry.</p> |
| <h5 id="errors-1"><a href="#errors-1">Errors</a></h5> |
| <p>If the map already had this key present, nothing is updated, and |
| an error containing the occupied entry and the value is returned.</p> |
| <h5 id="examples-37"><a href="#examples-37">Examples</a></h5> |
| <p>Basic usage:</p> |
| |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| <span class="kw">use </span>hashbrown::hash_map::OccupiedError; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| <span class="macro">assert_eq!</span>(map.try_insert(<span class="number">37</span>, <span class="string">"a"</span>).unwrap(), <span class="kw-2">&</span><span class="string">"a"</span>); |
| |
| <span class="kw">match </span>map.try_insert(<span class="number">37</span>, <span class="string">"b"</span>) { |
| <span class="prelude-val">Err</span>(OccupiedError { entry, value }) => { |
| <span class="macro">assert_eq!</span>(entry.key(), <span class="kw-2">&</span><span class="number">37</span>); |
| <span class="macro">assert_eq!</span>(entry.get(), <span class="kw-2">&</span><span class="string">"a"</span>); |
| <span class="macro">assert_eq!</span>(value, <span class="string">"b"</span>); |
| } |
| <span class="kw">_ </span>=> <span class="macro">panic!</span>() |
| }</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.remove" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1813-1823">source</a><h4 class="code-header">pub fn <a href="#method.remove" class="fnname">remove</a><Q: ?Sized>(&mut self, k: &Q) -> Option<V><span class="where fmt-newline">where<br> K: Borrow<Q>,<br> Q: Hash + Eq,</span></h4></section></summary><div class="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 |
| <a href="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> and <a href="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> on the borrowed form <em>must</em> match those for |
| the key type.</p> |
| <h5 id="examples-38"><a href="#examples-38">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| <span class="comment">// The map is empty |
| </span><span class="macro">assert!</span>(map.is_empty() && map.capacity() == <span class="number">0</span>); |
| |
| map.insert(<span class="number">1</span>, <span class="string">"a"</span>); |
| <span class="kw">let </span>capacity_before_remove = map.capacity(); |
| |
| <span class="macro">assert_eq!</span>(map.remove(<span class="kw-2">&</span><span class="number">1</span>), <span class="prelude-val">Some</span>(<span class="string">"a"</span>)); |
| <span class="macro">assert_eq!</span>(map.remove(<span class="kw-2">&</span><span class="number">1</span>), <span class="prelude-val">None</span>); |
| |
| <span class="comment">// Now map holds none elements but capacity is equal to the old one |
| </span><span class="macro">assert!</span>(map.len() == <span class="number">0 </span>&& map.capacity() == capacity_before_remove);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.remove_entry" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1854-1861">source</a><h4 class="code-header">pub fn <a href="#method.remove_entry" class="fnname">remove_entry</a><Q: ?Sized>(&mut self, k: &Q) -> Option<(K, V)><span class="where fmt-newline">where<br> K: Borrow<Q>,<br> Q: Hash + Eq,</span></h4></section></summary><div class="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 |
| <a href="https://doc.rust-lang.org/std/hash/trait.Hash.html"><code>Hash</code></a> and <a href="https://doc.rust-lang.org/std/cmp/trait.Eq.html"><code>Eq</code></a> on the borrowed form <em>must</em> match those for |
| the key type.</p> |
| <h5 id="examples-39"><a href="#examples-39">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| <span class="comment">// The map is empty |
| </span><span class="macro">assert!</span>(map.is_empty() && map.capacity() == <span class="number">0</span>); |
| |
| map.insert(<span class="number">1</span>, <span class="string">"a"</span>); |
| <span class="kw">let </span>capacity_before_remove = map.capacity(); |
| |
| <span class="macro">assert_eq!</span>(map.remove_entry(<span class="kw-2">&</span><span class="number">1</span>), <span class="prelude-val">Some</span>((<span class="number">1</span>, <span class="string">"a"</span>))); |
| <span class="macro">assert_eq!</span>(map.remove(<span class="kw-2">&</span><span class="number">1</span>), <span class="prelude-val">None</span>); |
| |
| <span class="comment">// Now map hold none elements but capacity is equal to the old one |
| </span><span class="macro">assert!</span>(map.len() == <span class="number">0 </span>&& map.capacity() == capacity_before_remove);</code></pre></div> |
| </div></details></div></details><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E-2" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1864-2076">source</a><a href="#impl-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E-2" class="anchor"></a><h3 class="code-header">impl<K, V, S, A: Allocator + Clone> <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.raw_entry_mut" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#1963-1965">source</a><h4 class="code-header">pub fn <a href="#method.raw_entry_mut" class="fnname">raw_entry_mut</a>(&mut self) -> <a class="struct" href="struct.RawEntryBuilderMut.html" title="struct hashbrown::hash_map::RawEntryBuilderMut">RawEntryBuilderMut</a><'_, K, V, S, A></h4></section></summary><div class="docblock"><p>Creates a raw 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. After this, insertions into a vacant entry |
| still require an owned key to be provided.</p> |
| <p>Raw entries are useful for such exotic situations as:</p> |
| <ul> |
| <li>Hash memoization</li> |
| <li>Deferring the creation of an owned key until it is known to be required</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>Because raw entries provide much more low-level control, it’s much easier |
| to put the HashMap into an inconsistent state which, while memory-safe, |
| will cause the map to produce seemingly random results. Higher-level and |
| more foolproof APIs like <code>entry</code> should be preferred when possible.</p> |
| <p>In particular, the hash used to initialized the raw entry must still be |
| consistent with the hash of the key that is ultimately stored in the entry. |
| This is because implementations of HashMap may need to recompute hashes |
| when resizing, at which point only the keys are available.</p> |
| <p>Raw entries give mutable access to the keys. This must not be used |
| to modify how the key would compare or hash, as the map will not re-evaluate |
| where the key should go, meaning the keys may become “lost” if their |
| location does not reflect their state. For instance, if you change a key |
| so that the map now contains keys which compare equal, search may start |
| acting erratically, with two keys randomly masking each other. Implementations |
| are free to assume this doesn’t happen (within the limits of memory-safety).</p> |
| <h5 id="examples-40"><a href="#examples-40">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>core::hash::{BuildHasher, Hash}; |
| <span class="kw">use </span>hashbrown::hash_map::{HashMap, RawEntryMut}; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| map.extend([(<span class="string">"a"</span>, <span class="number">100</span>), (<span class="string">"b"</span>, <span class="number">200</span>), (<span class="string">"c"</span>, <span class="number">300</span>)]); |
| |
| <span class="kw">fn </span>compute_hash<K: Hash + <span class="question-mark">?</span>Sized, S: BuildHasher>(hash_builder: <span class="kw-2">&</span>S, key: <span class="kw-2">&</span>K) -> u64 { |
| <span class="kw">use </span>core::hash::Hasher; |
| <span class="kw">let </span><span class="kw-2">mut </span>state = hash_builder.build_hasher(); |
| key.hash(<span class="kw-2">&mut </span>state); |
| state.finish() |
| } |
| |
| <span class="comment">// Existing key (insert and update) |
| </span><span class="kw">match </span>map.raw_entry_mut().from_key(<span class="kw-2">&</span><span class="string">"a"</span>) { |
| RawEntryMut::Vacant(<span class="kw">_</span>) => <span class="macro">unreachable!</span>(), |
| RawEntryMut::Occupied(<span class="kw-2">mut </span>view) => { |
| <span class="macro">assert_eq!</span>(view.get(), <span class="kw-2">&</span><span class="number">100</span>); |
| <span class="kw">let </span>v = view.get_mut(); |
| <span class="kw">let </span>new_v = (<span class="kw-2">*</span>v) * <span class="number">10</span>; |
| <span class="kw-2">*</span>v = new_v; |
| <span class="macro">assert_eq!</span>(view.insert(<span class="number">1111</span>), <span class="number">1000</span>); |
| } |
| } |
| |
| <span class="macro">assert_eq!</span>(map[<span class="kw-2">&</span><span class="string">"a"</span>], <span class="number">1111</span>); |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">3</span>); |
| |
| <span class="comment">// Existing key (take) |
| </span><span class="kw">let </span>hash = compute_hash(map.hasher(), <span class="kw-2">&</span><span class="string">"c"</span>); |
| <span class="kw">match </span>map.raw_entry_mut().from_key_hashed_nocheck(hash, <span class="kw-2">&</span><span class="string">"c"</span>) { |
| RawEntryMut::Vacant(<span class="kw">_</span>) => <span class="macro">unreachable!</span>(), |
| RawEntryMut::Occupied(view) => { |
| <span class="macro">assert_eq!</span>(view.remove_entry(), (<span class="string">"c"</span>, <span class="number">300</span>)); |
| } |
| } |
| <span class="macro">assert_eq!</span>(map.raw_entry().from_key(<span class="kw-2">&</span><span class="string">"c"</span>), <span class="prelude-val">None</span>); |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">2</span>); |
| |
| <span class="comment">// Nonexistent key (insert and update) |
| </span><span class="kw">let </span>key = <span class="string">"d"</span>; |
| <span class="kw">let </span>hash = compute_hash(map.hasher(), <span class="kw-2">&</span>key); |
| <span class="kw">match </span>map.raw_entry_mut().from_hash(hash, |q| <span class="kw-2">*</span>q == key) { |
| RawEntryMut::Occupied(<span class="kw">_</span>) => <span class="macro">unreachable!</span>(), |
| RawEntryMut::Vacant(view) => { |
| <span class="kw">let </span>(k, value) = view.insert(<span class="string">"d"</span>, <span class="number">4000</span>); |
| <span class="macro">assert_eq!</span>((<span class="kw-2">*</span>k, <span class="kw-2">*</span>value), (<span class="string">"d"</span>, <span class="number">4000</span>)); |
| <span class="kw-2">*</span>value = <span class="number">40000</span>; |
| } |
| } |
| <span class="macro">assert_eq!</span>(map[<span class="kw-2">&</span><span class="string">"d"</span>], <span class="number">40000</span>); |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">3</span>); |
| |
| <span class="kw">match </span>map.raw_entry_mut().from_hash(hash, |q| <span class="kw-2">*</span>q == key) { |
| RawEntryMut::Vacant(<span class="kw">_</span>) => <span class="macro">unreachable!</span>(), |
| RawEntryMut::Occupied(view) => { |
| <span class="macro">assert_eq!</span>(view.remove_entry(), (<span class="string">"d"</span>, <span class="number">40000</span>)); |
| } |
| } |
| <span class="macro">assert_eq!</span>(map.get(<span class="kw-2">&</span><span class="string">"d"</span>), <span class="prelude-val">None</span>); |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">2</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.raw_entry" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#2012-2014">source</a><h4 class="code-header">pub fn <a href="#method.raw_entry" class="fnname">raw_entry</a>(&self) -> <a class="struct" href="struct.RawEntryBuilder.html" title="struct hashbrown::hash_map::RawEntryBuilder">RawEntryBuilder</a><'_, K, V, S, A></h4></section></summary><div class="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> |
| <h5 id="examples-41"><a href="#examples-41">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>core::hash::{BuildHasher, Hash}; |
| <span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| map.extend([(<span class="string">"a"</span>, <span class="number">100</span>), (<span class="string">"b"</span>, <span class="number">200</span>), (<span class="string">"c"</span>, <span class="number">300</span>)]); |
| |
| <span class="kw">fn </span>compute_hash<K: Hash + <span class="question-mark">?</span>Sized, S: BuildHasher>(hash_builder: <span class="kw-2">&</span>S, key: <span class="kw-2">&</span>K) -> u64 { |
| <span class="kw">use </span>core::hash::Hasher; |
| <span class="kw">let </span><span class="kw-2">mut </span>state = hash_builder.build_hasher(); |
| key.hash(<span class="kw-2">&mut </span>state); |
| state.finish() |
| } |
| |
| <span class="kw">for </span>k <span class="kw">in </span>[<span class="string">"a"</span>, <span class="string">"b"</span>, <span class="string">"c"</span>, <span class="string">"d"</span>, <span class="string">"e"</span>, <span class="string">"f"</span>] { |
| <span class="kw">let </span>hash = compute_hash(map.hasher(), k); |
| <span class="kw">let </span>v = map.get(<span class="kw-2">&</span>k).cloned(); |
| <span class="kw">let </span>kv = v.as_ref().map(|v| (<span class="kw-2">&</span>k, v)); |
| |
| <span class="macro">println!</span>(<span class="string">"Key: {} and value: {:?}"</span>, k, v); |
| |
| <span class="macro">assert_eq!</span>(map.raw_entry().from_key(<span class="kw-2">&</span>k), kv); |
| <span class="macro">assert_eq!</span>(map.raw_entry().from_hash(hash, |q| <span class="kw-2">*</span>q == k), kv); |
| <span class="macro">assert_eq!</span>(map.raw_entry().from_key_hashed_nocheck(hash, <span class="kw-2">&</span>k), kv); |
| }</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.raw_table" class="method has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#2073-2075">source</a><h4 class="code-header">pub fn <a href="#method.raw_table" class="fnname">raw_table</a>(&mut self) -> &mut <a class="struct" href="../raw/struct.RawTable.html" title="struct hashbrown::raw::RawTable">RawTable</a><(K, V), A></h4></section></summary><div class="docblock"><p>Returns a mutable reference to the <a href="raw/struct.RawTable.html"><code>RawTable</code></a> used underneath <a href="struct.HashMap.html"><code>HashMap</code></a>. |
| This function is only available if the <code>raw</code> feature of the crate is enabled.</p> |
| <h5 id="note"><a href="#note">Note</a></h5> |
| <p>Calling the function safe, but using raw hash table API’s 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><a href="https://doc.rust-lang.org/reference/behavior-considered-undefined.html">undefined behavior</a></em>.</p> |
| <h5 id="examples-42"><a href="#examples-42">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>core::hash::{BuildHasher, Hash}; |
| <span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| map.extend([(<span class="string">"a"</span>, <span class="number">10</span>), (<span class="string">"b"</span>, <span class="number">20</span>), (<span class="string">"c"</span>, <span class="number">30</span>)]); |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">3</span>); |
| |
| <span class="comment">// Let's imagine that we have a value and a hash of the key, but not the key itself. |
| // However, if you want to remove the value from the map by hash and value, and you |
| // know exactly that the value is unique, then you can create a function like this: |
| </span><span class="kw">fn </span>remove_by_hash<K, V, S, F>( |
| map: <span class="kw-2">&mut </span>HashMap<K, V, S>, |
| hash: u64, |
| is_match: F, |
| ) -> <span class="prelude-ty">Option</span><(K, V)> |
| <span class="kw">where |
| </span>F: Fn(<span class="kw-2">&</span>(K, V)) -> bool, |
| { |
| <span class="kw">let </span>raw_table = map.raw_table(); |
| <span class="kw">match </span>raw_table.find(hash, is_match) { |
| <span class="prelude-val">Some</span>(bucket) => <span class="prelude-val">Some</span>(<span class="kw">unsafe </span>{ raw_table.remove(bucket) }), |
| <span class="prelude-val">None </span>=> <span class="prelude-val">None</span>, |
| } |
| } |
| |
| <span class="kw">fn </span>compute_hash<K: Hash + <span class="question-mark">?</span>Sized, S: BuildHasher>(hash_builder: <span class="kw-2">&</span>S, key: <span class="kw-2">&</span>K) -> u64 { |
| <span class="kw">use </span>core::hash::Hasher; |
| <span class="kw">let </span><span class="kw-2">mut </span>state = hash_builder.build_hasher(); |
| key.hash(<span class="kw-2">&mut </span>state); |
| state.finish() |
| } |
| |
| <span class="kw">let </span>hash = compute_hash(map.hasher(), <span class="string">"a"</span>); |
| <span class="macro">assert_eq!</span>(remove_by_hash(<span class="kw-2">&mut </span>map, hash, |(<span class="kw">_</span>, v)| <span class="kw-2">*</span>v == <span class="number">10</span>), <span class="prelude-val">Some</span>((<span class="string">"a"</span>, <span class="number">10</span>))); |
| <span class="macro">assert_eq!</span>(map.get(<span class="kw-2">&</span><span class="string">"a"</span>), <span class="prelude-val">None</span>); |
| <span class="macro">assert_eq!</span>(map.len(), <span class="number">2</span>);</code></pre></div> |
| </div></details></div></details></div><h2 id="trait-implementations" class="small-section-header">Trait Implementations<a href="#trait-implementations" class="anchor"></a></h2><div id="trait-implementations-list"><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-Clone-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#193-207">source</a><a href="#impl-Clone-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<K: Clone, V: Clone, S: Clone, A: Allocator + Clone> Clone for <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.clone" class="method trait-impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#194-199">source</a><a href="#method.clone" class="anchor"></a><h4 class="code-header">fn <a class="fnname">clone</a>(&self) -> Self</h4></section></summary><div class='docblock'>Returns a copy of the value. <a>Read more</a></div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.clone_from" class="method trait-impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#201-206">source</a><a href="#method.clone_from" class="anchor"></a><h4 class="code-header">fn <a class="fnname">clone_from</a>(&mut self, source: &Self)</h4></section></summary><div class='docblock'>Performs copy-assignment from <code>source</code>. <a>Read more</a></div></details></div></details><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-Debug-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#2104-2113">source</a><a href="#impl-Debug-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<K, V, S, A> Debug for <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><span class="where fmt-newline">where<br> K: Debug,<br> V: Debug,<br> A: Allocator + Clone,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.fmt" class="method trait-impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#2110-2112">source</a><a href="#method.fmt" class="anchor"></a><h4 class="code-header">fn <a class="fnname">fmt</a>(&self, f: &mut Formatter<'_>) -> Result</h4></section></summary><div class='docblock'>Formats the value using the given formatter. <a>Read more</a></div></details></div></details><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-Default-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#2115-2139">source</a><a href="#impl-Default-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<K, V, S, A> Default for <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><span class="where fmt-newline">where<br> S: Default,<br> A: Default + Allocator + Clone,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.default" class="method trait-impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#2136-2138">source</a><a href="#method.default" class="anchor"></a><h4 class="code-header">fn <a class="fnname">default</a>() -> Self</h4></section></summary><div class="docblock"><p>Creates an empty <code>HashMap<K, V, S, A></code>, with the <code>Default</code> value for the hasher and allocator.</p> |
| <h5 id="examples-43"><a href="#examples-43">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| <span class="kw">use </span>std::collections::hash_map::RandomState; |
| |
| <span class="comment">// You can specify all types of HashMap, including hasher and allocator. |
| // Created map is empty and don't allocate memory |
| </span><span class="kw">let </span>map: HashMap<u32, String> = Default::default(); |
| <span class="macro">assert_eq!</span>(map.capacity(), <span class="number">0</span>); |
| <span class="kw">let </span>map: HashMap<u32, String, RandomState> = HashMap::default(); |
| <span class="macro">assert_eq!</span>(map.capacity(), <span class="number">0</span>);</code></pre></div> |
| </div></details></div></details><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-Extend%3C%26%27a%20(K%2C%20V)%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#6501-6557">source</a><a href="#impl-Extend%3C%26%27a%20(K%2C%20V)%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<'a, K, V, S, A> Extend<&'a (K, V)> for <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><span class="where fmt-newline">where<br> K: Eq + Hash + Copy,<br> V: Copy,<br> S: BuildHasher,<br> A: Allocator + Clone,</span></h3></section></summary><div class="docblock"><p>Inserts all new key-values from the iterator and replaces values with existing |
| keys with new values returned from the iterator.</p> |
| </div><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.extend-2" class="method trait-impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#6542-6544">source</a><a href="#method.extend-2" class="anchor"></a><h4 class="code-header">fn <a class="fnname">extend</a><T: IntoIterator<Item = &'a (K, V)>>(&mut self, iter: T)</h4></section></summary><div class="docblock"><p>Inserts all new key-values from the iterator to existing <code>HashMap<K, V, S, A></code>. |
| Replace values with existing keys with new values returned from the iterator. |
| The keys and values must implement <a href="https://doc.rust-lang.org/core/marker/trait.Copy.html"><code>Copy</code></a> trait.</p> |
| <h5 id="examples-50"><a href="#examples-50">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::hash_map::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| map.insert(<span class="number">1</span>, <span class="number">100</span>); |
| |
| <span class="kw">let </span>arr = [(<span class="number">1</span>, <span class="number">1</span>), (<span class="number">2</span>, <span class="number">2</span>)]; |
| <span class="kw">let </span>some_iter = arr.iter(); |
| map.extend(some_iter); |
| <span class="comment">// Replace values with existing keys with new values returned from the iterator. |
| // So that the map.get(&1) doesn't return Some(&100). |
| </span><span class="macro">assert_eq!</span>(map.get(<span class="kw-2">&</span><span class="number">1</span>), <span class="prelude-val">Some</span>(<span class="kw-2">&</span><span class="number">1</span>)); |
| |
| <span class="kw">let </span>some_vec: Vec<<span class="kw">_</span>> = <span class="macro">vec!</span>[(<span class="number">3</span>, <span class="number">3</span>), (<span class="number">4</span>, <span class="number">4</span>)]; |
| map.extend(<span class="kw-2">&</span>some_vec); |
| |
| <span class="kw">let </span>some_arr = [(<span class="number">5</span>, <span class="number">5</span>), (<span class="number">6</span>, <span class="number">6</span>)]; |
| map.extend(<span class="kw-2">&</span>some_arr); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>vec: Vec<<span class="kw">_</span>> = map.into_iter().collect(); |
| <span class="comment">// The `IntoIter` iterator produces items in arbitrary order, so the |
| // items must be sorted to test them against a sorted array. |
| </span>vec.sort_unstable(); |
| <span class="macro">assert_eq!</span>(vec, [(<span class="number">1</span>, <span class="number">1</span>), (<span class="number">2</span>, <span class="number">2</span>), (<span class="number">3</span>, <span class="number">3</span>), (<span class="number">4</span>, <span class="number">4</span>), (<span class="number">5</span>, <span class="number">5</span>), (<span class="number">6</span>, <span class="number">6</span>)]);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.extend_one-2" class="method trait-impl has-srclink"><a href="#method.extend_one-2" class="anchor"></a><h4 class="code-header">fn <a class="fnname">extend_one</a>(&mut self, item: A)</h4></section></summary><span class="item-info"><div class="stab unstable"><span class="emoji">🔬</span><span>This is a nightly-only experimental API. (<code>extend_one</code>)</span></div></span><div class='docblock'>Extends a collection with exactly one element.</div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.extend_reserve-2" class="method trait-impl has-srclink"><a href="#method.extend_reserve-2" class="anchor"></a><h4 class="code-header">fn <a class="fnname">extend_reserve</a>(&mut self, additional: usize)</h4></section></summary><span class="item-info"><div class="stab unstable"><span class="emoji">🔬</span><span>This is a nightly-only experimental API. (<code>extend_one</code>)</span></div></span><div class='docblock'>Reserves capacity in a collection for the given number of additional elements. <a>Read more</a></div></details></div></details><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-Extend%3C(%26%27a%20K%2C%20%26%27a%20V)%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#6436-6497">source</a><a href="#impl-Extend%3C(%26%27a%20K%2C%20%26%27a%20V)%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<'a, K, V, S, A> Extend<(&'a K, &'a V)> for <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><span class="where fmt-newline">where<br> K: Eq + Hash + Copy,<br> V: Copy,<br> S: BuildHasher,<br> A: Allocator + Clone,</span></h3></section></summary><div class="docblock"><p>Inserts all new key-values from the iterator and replaces values with existing |
| keys with new values returned from the iterator.</p> |
| </div><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.extend-1" class="method trait-impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#6482-6484">source</a><a href="#method.extend-1" class="anchor"></a><h4 class="code-header">fn <a class="fnname">extend</a><T: IntoIterator<Item = (&'a K, &'a V)>>(&mut self, iter: T)</h4></section></summary><div class="docblock"><p>Inserts all new key-values from the iterator to existing <code>HashMap<K, V, S, A></code>. |
| Replace values with existing keys with new values returned from the iterator. |
| The keys and values must implement <a href="https://doc.rust-lang.org/core/marker/trait.Copy.html"><code>Copy</code></a> trait.</p> |
| <h5 id="examples-49"><a href="#examples-49">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::hash_map::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| map.insert(<span class="number">1</span>, <span class="number">100</span>); |
| |
| <span class="kw">let </span>arr = [(<span class="number">1</span>, <span class="number">1</span>), (<span class="number">2</span>, <span class="number">2</span>)]; |
| <span class="kw">let </span>some_iter = arr.iter().map(|<span class="kw-2">&</span>(k, v)| (k, v)); |
| map.extend(some_iter); |
| <span class="comment">// Replace values with existing keys with new values returned from the iterator. |
| // So that the map.get(&1) doesn't return Some(&100). |
| </span><span class="macro">assert_eq!</span>(map.get(<span class="kw-2">&</span><span class="number">1</span>), <span class="prelude-val">Some</span>(<span class="kw-2">&</span><span class="number">1</span>)); |
| |
| <span class="kw">let </span>some_vec: Vec<<span class="kw">_</span>> = <span class="macro">vec!</span>[(<span class="number">3</span>, <span class="number">3</span>), (<span class="number">4</span>, <span class="number">4</span>)]; |
| map.extend(some_vec.iter().map(|<span class="kw-2">&</span>(k, v)| (k, v))); |
| |
| <span class="kw">let </span>some_arr = [(<span class="number">5</span>, <span class="number">5</span>), (<span class="number">6</span>, <span class="number">6</span>)]; |
| map.extend(some_arr.iter().map(|<span class="kw-2">&</span>(k, v)| (k, v))); |
| |
| <span class="comment">// You can also extend from another HashMap |
| </span><span class="kw">let </span><span class="kw-2">mut </span>new_map = HashMap::new(); |
| new_map.extend(<span class="kw-2">&</span>map); |
| <span class="macro">assert_eq!</span>(new_map, map); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>vec: Vec<<span class="kw">_</span>> = new_map.into_iter().collect(); |
| <span class="comment">// The `IntoIter` iterator produces items in arbitrary order, so the |
| // items must be sorted to test them against a sorted array. |
| </span>vec.sort_unstable(); |
| <span class="macro">assert_eq!</span>(vec, [(<span class="number">1</span>, <span class="number">1</span>), (<span class="number">2</span>, <span class="number">2</span>), (<span class="number">3</span>, <span class="number">3</span>), (<span class="number">4</span>, <span class="number">4</span>), (<span class="number">5</span>, <span class="number">5</span>), (<span class="number">6</span>, <span class="number">6</span>)]);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.extend_one-1" class="method trait-impl has-srclink"><a href="#method.extend_one-1" class="anchor"></a><h4 class="code-header">fn <a class="fnname">extend_one</a>(&mut self, item: A)</h4></section></summary><span class="item-info"><div class="stab unstable"><span class="emoji">🔬</span><span>This is a nightly-only experimental API. (<code>extend_one</code>)</span></div></span><div class='docblock'>Extends a collection with exactly one element.</div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.extend_reserve-1" class="method trait-impl has-srclink"><a href="#method.extend_reserve-1" class="anchor"></a><h4 class="code-header">fn <a class="fnname">extend_reserve</a>(&mut self, additional: usize)</h4></section></summary><span class="item-info"><div class="stab unstable"><span class="emoji">🔬</span><span>This is a nightly-only experimental API. (<code>extend_one</code>)</span></div></span><div class='docblock'>Reserves capacity in a collection for the given number of additional elements. <a>Read more</a></div></details></div></details><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-Extend%3C(K%2C%20V)%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#6353-6432">source</a><a href="#impl-Extend%3C(K%2C%20V)%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<K, V, S, A> Extend<(K, V)> for <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><span class="where fmt-newline">where<br> K: Eq + Hash,<br> S: BuildHasher,<br> A: Allocator + Clone,</span></h3></section></summary><div class="docblock"><p>Inserts all new key-values from the iterator and replaces values with existing |
| keys with new values returned from the iterator.</p> |
| </div><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.extend" class="method trait-impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#6395-6410">source</a><a href="#method.extend" class="anchor"></a><h4 class="code-header">fn <a class="fnname">extend</a><T: IntoIterator<Item = (K, V)>>(&mut self, iter: T)</h4></section></summary><div class="docblock"><p>Inserts all new key-values from the iterator to existing <code>HashMap<K, V, S, A></code>. |
| Replace values with existing keys with new values returned from the iterator.</p> |
| <h5 id="examples-48"><a href="#examples-48">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::hash_map::HashMap; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>map = HashMap::new(); |
| map.insert(<span class="number">1</span>, <span class="number">100</span>); |
| |
| <span class="kw">let </span>some_iter = [(<span class="number">1</span>, <span class="number">1</span>), (<span class="number">2</span>, <span class="number">2</span>)].into_iter(); |
| map.extend(some_iter); |
| <span class="comment">// Replace values with existing keys with new values returned from the iterator. |
| // So that the map.get(&1) doesn't return Some(&100). |
| </span><span class="macro">assert_eq!</span>(map.get(<span class="kw-2">&</span><span class="number">1</span>), <span class="prelude-val">Some</span>(<span class="kw-2">&</span><span class="number">1</span>)); |
| |
| <span class="kw">let </span>some_vec: Vec<<span class="kw">_</span>> = <span class="macro">vec!</span>[(<span class="number">3</span>, <span class="number">3</span>), (<span class="number">4</span>, <span class="number">4</span>)]; |
| map.extend(some_vec); |
| |
| <span class="kw">let </span>some_arr = [(<span class="number">5</span>, <span class="number">5</span>), (<span class="number">6</span>, <span class="number">6</span>)]; |
| map.extend(some_arr); |
| <span class="kw">let </span>old_map_len = map.len(); |
| |
| <span class="comment">// You can also extend from another HashMap |
| </span><span class="kw">let </span><span class="kw-2">mut </span>new_map = HashMap::new(); |
| new_map.extend(map); |
| <span class="macro">assert_eq!</span>(new_map.len(), old_map_len); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>vec: Vec<<span class="kw">_</span>> = new_map.into_iter().collect(); |
| <span class="comment">// The `IntoIter` iterator produces items in arbitrary order, so the |
| // items must be sorted to test them against a sorted array. |
| </span>vec.sort_unstable(); |
| <span class="macro">assert_eq!</span>(vec, [(<span class="number">1</span>, <span class="number">1</span>), (<span class="number">2</span>, <span class="number">2</span>), (<span class="number">3</span>, <span class="number">3</span>), (<span class="number">4</span>, <span class="number">4</span>), (<span class="number">5</span>, <span class="number">5</span>), (<span class="number">6</span>, <span class="number">6</span>)]);</code></pre></div> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.extend_one" class="method trait-impl has-srclink"><a href="#method.extend_one" class="anchor"></a><h4 class="code-header">fn <a class="fnname">extend_one</a>(&mut self, item: A)</h4></section></summary><span class="item-info"><div class="stab unstable"><span class="emoji">🔬</span><span>This is a nightly-only experimental API. (<code>extend_one</code>)</span></div></span><div class='docblock'>Extends a collection with exactly one element.</div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.extend_reserve" class="method trait-impl has-srclink"><a href="#method.extend_reserve" class="anchor"></a><h4 class="code-header">fn <a class="fnname">extend_reserve</a>(&mut self, additional: usize)</h4></section></summary><span class="item-info"><div class="stab unstable"><span class="emoji">🔬</span><span>This is a nightly-only experimental API. (<code>extend_one</code>)</span></div></span><div class='docblock'>Reserves capacity in a collection for the given number of additional elements. <a>Read more</a></div></details></div></details><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-From%3CHashMap%3CT%2C%20()%2C%20S%2C%20A%3E%3E-for-HashSet%3CT%2C%20S%2C%20A%3E" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/set.rs.html#1180-1187">source</a><a href="#impl-From%3CHashMap%3CT%2C%20()%2C%20S%2C%20A%3E%3E-for-HashSet%3CT%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<T, S, A> From<<a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><T, (), S, A>> for <a class="struct" href="../hash_set/struct.HashSet.html" title="struct hashbrown::hash_set::HashSet">HashSet</a><T, S, A><span class="where fmt-newline">where<br> A: Allocator + Clone,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.from" class="method trait-impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/set.rs.html#1184-1186">source</a><a href="#method.from" class="anchor"></a><h4 class="code-header">fn <a class="fnname">from</a>(map: <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><T, (), S, A>) -> Self</h4></section></summary><div class='docblock'>Converts to this type from the input type.</div></details></div></details><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-FromIterator%3C(K%2C%20V)%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#6333-6349">source</a><a href="#impl-FromIterator%3C(K%2C%20V)%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<K, V, S, A> FromIterator<(K, V)> for <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><span class="where fmt-newline">where<br> K: Eq + Hash,<br> S: BuildHasher + Default,<br> A: Default + Allocator + Clone,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.from_iter" class="method trait-impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#6340-6348">source</a><a href="#method.from_iter" class="anchor"></a><h4 class="code-header">fn <a class="fnname">from_iter</a><T: IntoIterator<Item = (K, V)>>(iter: T) -> Self</h4></section></summary><div class='docblock'>Creates a value from an iterator. <a>Read more</a></div></details></div></details><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-Index%3C%26Q%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#2141-2170">source</a><a href="#impl-Index%3C%26Q%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<K, Q: ?Sized, V, S, A> Index<&Q> for <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><span class="where fmt-newline">where<br> K: Eq + Hash + Borrow<Q>,<br> Q: Eq + Hash,<br> S: BuildHasher,<br> A: Allocator + Clone,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.index" class="method trait-impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#2167-2169">source</a><a href="#method.index" class="anchor"></a><h4 class="code-header">fn <a class="fnname">index</a>(&self, key: &Q) -> &V</h4></section></summary><div class="docblock"><p>Returns a reference to the value corresponding to the supplied key.</p> |
| <h5 id="panics-1"><a href="#panics-1">Panics</a></h5> |
| <p>Panics if the key is not present in the <code>HashMap</code>.</p> |
| <h5 id="examples-44"><a href="#examples-44">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span>map: HashMap<<span class="kw">_</span>, <span class="kw">_</span>> = [(<span class="string">"a"</span>, <span class="string">"One"</span>), (<span class="string">"b"</span>, <span class="string">"Two"</span>)].into(); |
| |
| <span class="macro">assert_eq!</span>(map[<span class="kw-2">&</span><span class="string">"a"</span>], <span class="string">"One"</span>); |
| <span class="macro">assert_eq!</span>(map[<span class="kw-2">&</span><span class="string">"b"</span>], <span class="string">"Two"</span>);</code></pre></div> |
| </div></details><details class="rustdoc-toggle" open><summary><section id="associatedtype.Output" class="associatedtype trait-impl has-srclink"><a href="#associatedtype.Output" class="anchor"></a><h4 class="code-header">type <a class="associatedtype">Output</a> = V</h4></section></summary><div class='docblock'>The returned type after indexing.</div></details></div></details><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-IntoIterator-for-%26%27a%20HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#4570-4600">source</a><a href="#impl-IntoIterator-for-%26%27a%20HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<'a, K, V, S, A: Allocator + Clone> IntoIterator for &'a <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.into_iter" class="method trait-impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#4597-4599">source</a><a href="#method.into_iter" class="anchor"></a><h4 class="code-header">fn <a class="fnname">into_iter</a>(self) -> <a class="struct" href="struct.Iter.html" title="struct hashbrown::hash_map::Iter">Iter</a><'a, K, V><span class="notable-traits"><span class="notable-traits-tooltip">ⓘ<span class="notable-traits-tooltiptext"><span class="docblock"><span class="notable">Notable traits for <a class="struct" href="struct.Iter.html" title="struct hashbrown::hash_map::Iter">Iter</a><'a, K, V></span><code class="content"><span class="where fmt-newline">impl<'a, K, V> Iterator for <a class="struct" href="struct.Iter.html" title="struct hashbrown::hash_map::Iter">Iter</a><'a, K, V></span><span class="where fmt-newline"> type <a class="associatedtype">Item</a> = (&'a K, &'a V);</span></code></span></span></span></span></h4></section></summary><div class="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 <a href="struct.HashMap.html#method.iter"><code>iter</code></a> method on <a href="struct.HashMap.html"><code>HashMap</code></a>.</p> |
| <h5 id="examples-45"><a href="#examples-45">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| <span class="kw">let </span>map_one: HashMap<<span class="kw">_</span>, <span class="kw">_</span>> = [(<span class="number">1</span>, <span class="string">"a"</span>), (<span class="number">2</span>, <span class="string">"b"</span>), (<span class="number">3</span>, <span class="string">"c"</span>)].into(); |
| <span class="kw">let </span><span class="kw-2">mut </span>map_two = HashMap::new(); |
| |
| <span class="kw">for </span>(key, value) <span class="kw">in </span><span class="kw-2">&</span>map_one { |
| <span class="macro">println!</span>(<span class="string">"Key: {}, Value: {}"</span>, key, value); |
| map_two.insert_unique_unchecked(<span class="kw-2">*</span>key, <span class="kw-2">*</span>value); |
| } |
| |
| <span class="macro">assert_eq!</span>(map_one, map_two);</code></pre></div> |
| </div></details><details class="rustdoc-toggle" open><summary><section id="associatedtype.Item" class="associatedtype trait-impl has-srclink"><a href="#associatedtype.Item" class="anchor"></a><h4 class="code-header">type <a class="associatedtype">Item</a> = (&'a K, &'a V)</h4></section></summary><div class='docblock'>The type of the elements being iterated over.</div></details><details class="rustdoc-toggle" open><summary><section id="associatedtype.IntoIter" class="associatedtype trait-impl has-srclink"><a href="#associatedtype.IntoIter" class="anchor"></a><h4 class="code-header">type <a class="associatedtype">IntoIter</a> = <a class="struct" href="struct.Iter.html" title="struct hashbrown::hash_map::Iter">Iter</a><'a, K, V></h4></section></summary><div class='docblock'>Which kind of iterator are we turning this into?</div></details></div></details><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-IntoIterator-for-%26%27a%20mut%20HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#4602-4637">source</a><a href="#impl-IntoIterator-for-%26%27a%20mut%20HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<'a, K, V, S, A: Allocator + Clone> IntoIterator for &'a mut <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.into_iter-1" class="method trait-impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#4634-4636">source</a><a href="#method.into_iter-1" class="anchor"></a><h4 class="code-header">fn <a class="fnname">into_iter</a>(self) -> <a class="struct" href="struct.IterMut.html" title="struct hashbrown::hash_map::IterMut">IterMut</a><'a, K, V><span class="notable-traits"><span class="notable-traits-tooltip">ⓘ<span class="notable-traits-tooltiptext"><span class="docblock"><span class="notable">Notable traits for <a class="struct" href="struct.IterMut.html" title="struct hashbrown::hash_map::IterMut">IterMut</a><'a, K, V></span><code class="content"><span class="where fmt-newline">impl<'a, K, V> Iterator for <a class="struct" href="struct.IterMut.html" title="struct hashbrown::hash_map::IterMut">IterMut</a><'a, K, V></span><span class="where fmt-newline"> type <a class="associatedtype">Item</a> = (&'a K, &'a mut V);</span></code></span></span></span></span></h4></section></summary><div class="docblock"><p>Creates an iterator over the entries of a <code>HashMap</code> in arbitrary order |
| with mutable references to the values. The iterator element type is |
| <code>(&'a K, &'a mut V)</code>.</p> |
| <p>Return the same <code>IterMut</code> struct as by the <a href="struct.HashMap.html#method.iter_mut"><code>iter_mut</code></a> method on |
| <a href="struct.HashMap.html"><code>HashMap</code></a>.</p> |
| <h5 id="examples-46"><a href="#examples-46">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| <span class="kw">let </span><span class="kw-2">mut </span>map: HashMap<<span class="kw">_</span>, <span class="kw">_</span>> = [(<span class="string">"a"</span>, <span class="number">1</span>), (<span class="string">"b"</span>, <span class="number">2</span>), (<span class="string">"c"</span>, <span class="number">3</span>)].into(); |
| |
| <span class="kw">for </span>(key, value) <span class="kw">in </span><span class="kw-2">&mut </span>map { |
| <span class="macro">println!</span>(<span class="string">"Key: {}, Value: {}"</span>, key, value); |
| <span class="kw-2">*</span>value <span class="kw-2">*</span>= <span class="number">2</span>; |
| } |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>vec = map.iter().collect::<Vec<<span class="kw">_</span>>>(); |
| <span class="comment">// The `Iter` iterator produces items in arbitrary order, so the |
| // items must be sorted to test them against a sorted array. |
| </span>vec.sort_unstable(); |
| <span class="macro">assert_eq!</span>(vec, [(<span class="kw-2">&</span><span class="string">"a"</span>, <span class="kw-2">&</span><span class="number">2</span>), (<span class="kw-2">&</span><span class="string">"b"</span>, <span class="kw-2">&</span><span class="number">4</span>), (<span class="kw-2">&</span><span class="string">"c"</span>, <span class="kw-2">&</span><span class="number">6</span>)]);</code></pre></div> |
| </div></details><details class="rustdoc-toggle" open><summary><section id="associatedtype.Item-1" class="associatedtype trait-impl has-srclink"><a href="#associatedtype.Item-1" class="anchor"></a><h4 class="code-header">type <a class="associatedtype">Item</a> = (&'a K, &'a mut V)</h4></section></summary><div class='docblock'>The type of the elements being iterated over.</div></details><details class="rustdoc-toggle" open><summary><section id="associatedtype.IntoIter-1" class="associatedtype trait-impl has-srclink"><a href="#associatedtype.IntoIter-1" class="anchor"></a><h4 class="code-header">type <a class="associatedtype">IntoIter</a> = <a class="struct" href="struct.IterMut.html" title="struct hashbrown::hash_map::IterMut">IterMut</a><'a, K, V></h4></section></summary><div class='docblock'>Which kind of iterator are we turning this into?</div></details></div></details><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-IntoIterator-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#4639-4667">source</a><a href="#impl-IntoIterator-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<K, V, S, A: Allocator + Clone> IntoIterator for <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.into_iter-2" class="method trait-impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#4662-4666">source</a><a href="#method.into_iter-2" class="anchor"></a><h4 class="code-header">fn <a class="fnname">into_iter</a>(self) -> <a class="struct" href="struct.IntoIter.html" title="struct hashbrown::hash_map::IntoIter">IntoIter</a><K, V, A><span class="notable-traits"><span class="notable-traits-tooltip">ⓘ<span class="notable-traits-tooltiptext"><span class="docblock"><span class="notable">Notable traits for <a class="struct" href="struct.IntoIter.html" title="struct hashbrown::hash_map::IntoIter">IntoIter</a><K, V, A></span><code class="content"><span class="where fmt-newline">impl<K, V, A: Allocator + Clone> Iterator for <a class="struct" href="struct.IntoIter.html" title="struct hashbrown::hash_map::IntoIter">IntoIter</a><K, V, A></span><span class="where fmt-newline"> type <a class="associatedtype">Item</a> = (K, V);</span></code></span></span></span></span></h4></section></summary><div class="docblock"><p>Creates a consuming iterator, that is, one that moves each key-value |
| pair out of the map in arbitrary order. The map cannot be used after |
| calling this.</p> |
| <h5 id="examples-47"><a href="#examples-47">Examples</a></h5> |
| <div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::HashMap; |
| |
| <span class="kw">let </span>map: HashMap<<span class="kw">_</span>, <span class="kw">_</span>> = [(<span class="string">"a"</span>, <span class="number">1</span>), (<span class="string">"b"</span>, <span class="number">2</span>), (<span class="string">"c"</span>, <span class="number">3</span>)].into(); |
| |
| <span class="comment">// Not possible with .iter() |
| </span><span class="kw">let </span><span class="kw-2">mut </span>vec: Vec<(<span class="kw-2">&</span>str, i32)> = map.into_iter().collect(); |
| <span class="comment">// The `IntoIter` iterator produces items in arbitrary order, so |
| // the items must be sorted to test them against a sorted array. |
| </span>vec.sort_unstable(); |
| <span class="macro">assert_eq!</span>(vec, [(<span class="string">"a"</span>, <span class="number">1</span>), (<span class="string">"b"</span>, <span class="number">2</span>), (<span class="string">"c"</span>, <span class="number">3</span>)]);</code></pre></div> |
| </div></details><details class="rustdoc-toggle" open><summary><section id="associatedtype.Item-2" class="associatedtype trait-impl has-srclink"><a href="#associatedtype.Item-2" class="anchor"></a><h4 class="code-header">type <a class="associatedtype">Item</a> = (K, V)</h4></section></summary><div class='docblock'>The type of the elements being iterated over.</div></details><details class="rustdoc-toggle" open><summary><section id="associatedtype.IntoIter-2" class="associatedtype trait-impl has-srclink"><a href="#associatedtype.IntoIter-2" class="anchor"></a><h4 class="code-header">type <a class="associatedtype">IntoIter</a> = <a class="struct" href="struct.IntoIter.html" title="struct hashbrown::hash_map::IntoIter">IntoIter</a><K, V, A></h4></section></summary><div class='docblock'>Which kind of iterator are we turning this into?</div></details></div></details><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-PartialEq%3CHashMap%3CK%2C%20V%2C%20S%2C%20A%3E%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#2078-2093">source</a><a href="#impl-PartialEq%3CHashMap%3CK%2C%20V%2C%20S%2C%20A%3E%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<K, V, S, A> PartialEq<<a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A>> for <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><span class="where fmt-newline">where<br> K: Eq + Hash,<br> V: PartialEq,<br> S: BuildHasher,<br> A: Allocator + Clone,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.eq" class="method trait-impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#2085-2092">source</a><a href="#method.eq" class="anchor"></a><h4 class="code-header">fn <a class="fnname">eq</a>(&self, other: &Self) -> bool</h4></section></summary><div class='docblock'>This method tests for <code>self</code> and <code>other</code> values to be equal, and is used |
| by <code>==</code>. <a>Read more</a></div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.ne" class="method trait-impl has-srclink"><span class="since rightside" title="Stable since Rust version 1.0.0">1.0.0</span><a href="#method.ne" class="anchor"></a><h4 class="code-header">const fn <a class="fnname">ne</a>(&self, other: &Rhs) -> bool</h4></section></summary><div class='docblock'>This method tests for <code>!=</code>. The default implementation is almost always |
| sufficient, and should not be overridden without very good reason. <a>Read more</a></div></details></div></details><section id="impl-Eq-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a class="srclink rightside" href="../../src/hashbrown/map.rs.html#2095-2102">source</a><a href="#impl-Eq-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<K, V, S, A> Eq for <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><span class="where fmt-newline">where<br> K: Eq + Hash,<br> V: Eq,<br> S: BuildHasher,<br> A: Allocator + Clone,</span></h3></section></div><h2 id="synthetic-implementations" class="small-section-header">Auto Trait Implementations<a href="#synthetic-implementations" class="anchor"></a></h2><div id="synthetic-implementations-list"><section id="impl-RefUnwindSafe-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a href="#impl-RefUnwindSafe-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<K, V, S, A> RefUnwindSafe for <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><span class="where fmt-newline">where<br> A: RefUnwindSafe,<br> K: RefUnwindSafe,<br> S: RefUnwindSafe,<br> V: RefUnwindSafe,</span></h3></section><section id="impl-Send-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a href="#impl-Send-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<K, V, S, A> Send for <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><span class="where fmt-newline">where<br> A: Send,<br> K: Send,<br> S: Send,<br> V: Send,</span></h3></section><section id="impl-Sync-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a href="#impl-Sync-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<K, V, S, A> Sync for <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><span class="where fmt-newline">where<br> A: Sync,<br> K: Sync,<br> S: Sync,<br> V: Sync,</span></h3></section><section id="impl-Unpin-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a href="#impl-Unpin-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<K, V, S, A> Unpin for <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><span class="where fmt-newline">where<br> A: Unpin,<br> K: Unpin,<br> S: Unpin,<br> V: Unpin,</span></h3></section><section id="impl-UnwindSafe-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a href="#impl-UnwindSafe-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<K, V, S, A> UnwindSafe for <a class="struct" href="struct.HashMap.html" title="struct hashbrown::hash_map::HashMap">HashMap</a><K, V, S, A><span class="where fmt-newline">where<br> A: UnwindSafe,<br> K: UnwindSafe,<br> S: UnwindSafe,<br> V: UnwindSafe,</span></h3></section></div><h2 id="blanket-implementations" class="small-section-header">Blanket Implementations<a href="#blanket-implementations" class="anchor"></a></h2><div id="blanket-implementations-list"><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-Any-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a href="#impl-Any-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<T> Any for T<span class="where fmt-newline">where<br> T: 'static + ?Sized,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.type_id" class="method trait-impl has-srclink"><a href="#method.type_id" class="anchor"></a><h4 class="code-header">fn <a class="fnname">type_id</a>(&self) -> TypeId</h4></section></summary><div class='docblock'>Gets the <code>TypeId</code> of <code>self</code>. <a>Read more</a></div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-Borrow%3CT%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a href="#impl-Borrow%3CT%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<T> Borrow<T> for T<span class="where fmt-newline">where<br> T: ?Sized,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.borrow" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/91522" title="Tracking issue for const_borrow">unstable</a></span><a href="#method.borrow" class="anchor"></a><h4 class="code-header">fn <a class="fnname">borrow</a>(&self) -> &T</h4></section></summary><div class='docblock'>Immutably borrows from an owned value. <a>Read more</a></div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-BorrowMut%3CT%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a href="#impl-BorrowMut%3CT%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<T> BorrowMut<T> for T<span class="where fmt-newline">where<br> T: ?Sized,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.borrow_mut" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/91522" title="Tracking issue for const_borrow">unstable</a></span><a href="#method.borrow_mut" class="anchor"></a><h4 class="code-header">fn <a class="fnname">borrow_mut</a>(&mut self) -> &mut T</h4></section></summary><div class='docblock'>Mutably borrows from an owned value. <a>Read more</a></div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-From%3CT%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a href="#impl-From%3CT%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<T> From<T> for T</h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.from-1" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/88674" title="Tracking issue for const_convert">unstable</a></span><a href="#method.from-1" class="anchor"></a><h4 class="code-header">fn <a class="fnname">from</a>(t: T) -> T</h4></section></summary><div class="docblock"><p>Returns the argument unchanged.</p> |
| </div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-Into%3CU%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a href="#impl-Into%3CU%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<T, U> Into<U> for T<span class="where fmt-newline">where<br> U: From<T>,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.into" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/88674" title="Tracking issue for const_convert">unstable</a></span><a href="#method.into" class="anchor"></a><h4 class="code-header">fn <a class="fnname">into</a>(self) -> U</h4></section></summary><div class="docblock"><p>Calls <code>U::from(self)</code>.</p> |
| <p>That is, this conversion is whatever the implementation of |
| <code>[From]<T> for U</code> chooses to do.</p> |
| </div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-ToOwned-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a href="#impl-ToOwned-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<T> ToOwned for T<span class="where fmt-newline">where<br> T: Clone,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle" open><summary><section id="associatedtype.Owned" class="associatedtype trait-impl has-srclink"><a href="#associatedtype.Owned" class="anchor"></a><h4 class="code-header">type <a class="associatedtype">Owned</a> = T</h4></section></summary><div class='docblock'>The resulting type after obtaining ownership.</div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.to_owned" class="method trait-impl has-srclink"><a href="#method.to_owned" class="anchor"></a><h4 class="code-header">fn <a class="fnname">to_owned</a>(&self) -> T</h4></section></summary><div class='docblock'>Creates owned data from borrowed data, usually by cloning. <a>Read more</a></div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.clone_into" class="method trait-impl has-srclink"><a href="#method.clone_into" class="anchor"></a><h4 class="code-header">fn <a class="fnname">clone_into</a>(&self, target: &mut T)</h4></section></summary><div class='docblock'>Uses borrowed data to replace owned data, usually by cloning. <a>Read more</a></div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-TryFrom%3CU%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a href="#impl-TryFrom%3CU%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<T, U> TryFrom<U> for T<span class="where fmt-newline">where<br> U: Into<T>,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle" open><summary><section id="associatedtype.Error-1" class="associatedtype trait-impl has-srclink"><a href="#associatedtype.Error-1" class="anchor"></a><h4 class="code-header">type <a class="associatedtype">Error</a> = Infallible</h4></section></summary><div class='docblock'>The type returned in the event of a conversion error.</div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.try_from" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/88674" title="Tracking issue for const_convert">unstable</a></span><a href="#method.try_from" class="anchor"></a><h4 class="code-header">fn <a class="fnname">try_from</a>(value: U) -> Result<T, <T as TryFrom<U>>::Error></h4></section></summary><div class='docblock'>Performs the conversion.</div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-TryInto%3CU%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="impl has-srclink"><a href="#impl-TryInto%3CU%3E-for-HashMap%3CK%2C%20V%2C%20S%2C%20A%3E" class="anchor"></a><h3 class="code-header">impl<T, U> TryInto<U> for T<span class="where fmt-newline">where<br> U: TryFrom<T>,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle" open><summary><section id="associatedtype.Error" class="associatedtype trait-impl has-srclink"><a href="#associatedtype.Error" class="anchor"></a><h4 class="code-header">type <a class="associatedtype">Error</a> = <U as TryFrom<T>>::Error</h4></section></summary><div class='docblock'>The type returned in the event of a conversion error.</div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.try_into" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/88674" title="Tracking issue for const_convert">unstable</a></span><a href="#method.try_into" class="anchor"></a><h4 class="code-header">fn <a class="fnname">try_into</a>(self) -> Result<U, <U as TryFrom<T>>::Error></h4></section></summary><div class='docblock'>Performs the conversion.</div></details></div></details></div></section></div></main><div id="rustdoc-vars" data-root-path="../../" data-current-crate="hashbrown" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |