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<!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 view into an occupied entry in a `HashMap`. It is part of the `Entry` enum."><title>OccupiedEntry in hashbrown::hash_map - Rust</title><script>if(window.location.protocol!=="file:")document.head.insertAdjacentHTML("beforeend","SourceSerif4-Regular-46f98efaafac5295.ttf.woff2,FiraSans-Regular-018c141bf0843ffd.woff2,FiraSans-Medium-8f9a781e4970d388.woff2,SourceCodePro-Regular-562dcc5011b6de7d.ttf.woff2,SourceCodePro-Semibold-d899c5a5c4aeb14a.ttf.woff2".split(",").map(f=>`<link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/${f}">`).join(""))</script><link rel="stylesheet" href="../../static.files/normalize-76eba96aa4d2e634.css"><link rel="stylesheet" href="../../static.files/rustdoc-dd39b87e5fcfba68.css"><meta name="rustdoc-vars" data-root-path="../../" data-static-root-path="../../static.files/" data-current-crate="hashbrown" data-themes="" data-resource-suffix="" data-rustdoc-version="1.80.0 (051478957 2024-07-21)" data-channel="1.80.0" data-search-js="search-d52510db62a78183.js" data-settings-js="settings-4313503d2e1961c2.js" ><script src="../../static.files/storage-118b08c4c78b968e.js"></script><script defer src="sidebar-items.js"></script><script defer src="../../static.files/main-20a3ad099b048cf2.js"></script><noscript><link rel="stylesheet" href="../../static.files/noscript-df360f571f6edeae.css"></noscript><link rel="alternate icon" type="image/png" href="../../static.files/favicon-32x32-422f7d1d52889060.png"><link rel="icon" type="image/svg+xml" href="../../static.files/favicon-2c020d218678b618.svg"></head><body class="rustdoc struct"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="mobile-topbar"><button class="sidebar-menu-toggle" title="show sidebar"></button></nav><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../../hashbrown/index.html">hashbrown</a><span class="version">0.14.5</span></h2></div><h2 class="location"><a href="#">OccupiedEntry</a></h2><div class="sidebar-elems"><section><h3><a href="#implementations">Methods</a></h3><ul class="block method"><li><a href="#method.get">get</a></li><li><a href="#method.get_mut">get_mut</a></li><li><a href="#method.insert">insert</a></li><li><a href="#method.into_mut">into_mut</a></li><li><a href="#method.key">key</a></li><li><a href="#method.remove">remove</a></li><li><a href="#method.remove_entry">remove_entry</a></li><li><a href="#method.replace_entry">replace_entry</a></li><li><a href="#method.replace_entry_with">replace_entry_with</a></li><li><a href="#method.replace_key">replace_key</a></li></ul><h3><a href="#trait-implementations">Trait Implementations</a></h3><ul class="block trait-implementation"><li><a href="#impl-Debug-for-OccupiedEntry%3C'_,+K,+V,+S,+A%3E">Debug</a></li><li><a href="#impl-Send-for-OccupiedEntry%3C'_,+K,+V,+S,+A%3E">Send</a></li><li><a href="#impl-Sync-for-OccupiedEntry%3C'_,+K,+V,+S,+A%3E">Sync</a></li></ul><h3><a href="#synthetic-implementations">Auto Trait Implementations</a></h3><ul class="block synthetic-implementation"><li><a href="#impl-UnwindSafe-for-OccupiedEntry%3C'a,+K,+V,+S,+A%3E">!UnwindSafe</a></li><li><a href="#impl-Freeze-for-OccupiedEntry%3C'a,+K,+V,+S,+A%3E">Freeze</a></li><li><a href="#impl-RefUnwindSafe-for-OccupiedEntry%3C'a,+K,+V,+S,+A%3E">RefUnwindSafe</a></li><li><a href="#impl-Unpin-for-OccupiedEntry%3C'a,+K,+V,+S,+A%3E">Unpin</a></li></ul><h3><a href="#blanket-implementations">Blanket Implementations</a></h3><ul class="block blanket-implementation"><li><a href="#impl-Any-for-T">Any</a></li><li><a href="#impl-Borrow%3CT%3E-for-T">Borrow&lt;T&gt;</a></li><li><a href="#impl-BorrowMut%3CT%3E-for-T">BorrowMut&lt;T&gt;</a></li><li><a href="#impl-From%3CT%3E-for-T">From&lt;T&gt;</a></li><li><a href="#impl-Into%3CU%3E-for-T">Into&lt;U&gt;</a></li><li><a href="#impl-TryFrom%3CU%3E-for-T">TryFrom&lt;U&gt;</a></li><li><a href="#impl-TryInto%3CU%3E-for-T">TryInto&lt;U&gt;</a></li></ul></section><h2><a href="index.html">In hashbrown::hash_map</a></h2></div></nav><div class="sidebar-resizer"></div><main><div class="width-limiter"><rustdoc-search></rustdoc-search><section id="main-content" class="content"><div class="main-heading"><h1>Struct <a href="../index.html">hashbrown</a>::<wbr><a href="index.html">hash_map</a>::<wbr><a class="struct" href="#">OccupiedEntry</a><button id="copy-path" title="Copy item path to clipboard">Copy item path</button></h1><span class="out-of-band"><a class="src" href="../../src/hashbrown/map.rs.html#4250-4255">source</a> · <button id="toggle-all-docs" title="collapse all docs">[<span>&#x2212;</span>]</button></span></div><pre class="rust item-decl"><code>pub struct OccupiedEntry&lt;'a, K, V, S = <a class="enum" href="enum.DefaultHashBuilder.html" title="enum hashbrown::hash_map::DefaultHashBuilder">DefaultHashBuilder</a>, A: Allocator = Global&gt; { <span class="comment">/* private fields */</span> }</code></pre><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>A view into an occupied entry in a <code>HashMap</code>.
It is part of the <a href="enum.Entry.html"><code>Entry</code></a> enum.</p>
<h2 id="examples"><a class="doc-anchor" href="#examples">§</a>Examples</h2>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::hash_map::{Entry, HashMap, OccupiedEntry};
<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="kw">let </span>_entry_o: OccupiedEntry&lt;<span class="kw">_</span>, <span class="kw">_</span>, <span class="kw">_</span>&gt; = map.entry(<span class="string">"a"</span>).insert(<span class="number">100</span>);
<span class="macro">assert_eq!</span>(map.len(), <span class="number">3</span>);
<span class="comment">// Existing key (insert and update)
</span><span class="kw">match </span>map.entry(<span class="string">"a"</span>) {
Entry::Vacant(<span class="kw">_</span>) =&gt; <span class="macro">unreachable!</span>(),
Entry::Occupied(<span class="kw-2">mut </span>view) =&gt; {
<span class="macro">assert_eq!</span>(view.get(), <span class="kw-2">&amp;</span><span class="number">100</span>);
<span class="kw">let </span>v = view.get_mut();
<span class="kw-2">*</span>v <span class="kw-2">*</span>= <span class="number">10</span>;
<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">&amp;</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">match </span>map.entry(<span class="string">"c"</span>) {
Entry::Vacant(<span class="kw">_</span>) =&gt; <span class="macro">unreachable!</span>(),
Entry::Occupied(view) =&gt; {
<span class="macro">assert_eq!</span>(view.remove_entry(), (<span class="string">"c"</span>, <span class="number">30</span>));
}
}
<span class="macro">assert_eq!</span>(map.get(<span class="kw-2">&amp;</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>);</code></pre></div>
</div></details><h2 id="implementations" class="section-header">Implementations<a href="#implementations" class="anchor">§</a></h2><div id="implementations-list"><details class="toggle implementors-toggle" open><summary><section id="impl-OccupiedEntry%3C'a,+K,+V,+S,+A%3E" class="impl"><a class="src rightside" href="../../src/hashbrown/map.rs.html#5267-5620">source</a><a href="#impl-OccupiedEntry%3C'a,+K,+V,+S,+A%3E" class="anchor">§</a><h3 class="code-header">impl&lt;'a, K, V, S, A: Allocator&gt; <a class="struct" href="struct.OccupiedEntry.html" title="struct hashbrown::hash_map::OccupiedEntry">OccupiedEntry</a>&lt;'a, K, V, S, A&gt;</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.key" class="method"><a class="src rightside" href="../../src/hashbrown/map.rs.html#5284-5286">source</a><h4 class="code-header">pub fn <a href="#method.key" class="fn">key</a>(&amp;self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&amp;K</a></h4></section></summary><div class="docblock"><p>Gets a reference to the key in the entry.</p>
<h5 id="examples-1"><a class="doc-anchor" href="#examples-1">§</a>Examples</h5>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::hash_map::{Entry, HashMap};
<span class="kw">let </span><span class="kw-2">mut </span>map: HashMap&lt;<span class="kw-2">&amp;</span>str, u32&gt; = HashMap::new();
map.entry(<span class="string">"poneyland"</span>).or_insert(<span class="number">12</span>);
<span class="kw">match </span>map.entry(<span class="string">"poneyland"</span>) {
Entry::Vacant(<span class="kw">_</span>) =&gt; <span class="macro">panic!</span>(),
Entry::Occupied(entry) =&gt; <span class="macro">assert_eq!</span>(entry.key(), <span class="kw-2">&amp;</span><span class="string">"poneyland"</span>),
}</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.remove_entry" class="method"><a class="src rightside" href="../../src/hashbrown/map.rs.html#5313-5315">source</a><h4 class="code-header">pub fn <a href="#method.remove_entry" class="fn">remove_entry</a>(self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.80.0/core/primitive.tuple.html">(K, V)</a></h4></section></summary><div class="docblock"><p>Take the ownership of the key and value from the map.
Keeps the allocated memory for reuse.</p>
<h5 id="examples-2"><a class="doc-anchor" href="#examples-2">§</a>Examples</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::Entry;
<span class="kw">let </span><span class="kw-2">mut </span>map: HashMap&lt;<span class="kw-2">&amp;</span>str, u32&gt; = HashMap::new();
<span class="comment">// The map is empty
</span><span class="macro">assert!</span>(map.is_empty() &amp;&amp; map.capacity() == <span class="number">0</span>);
map.entry(<span class="string">"poneyland"</span>).or_insert(<span class="number">12</span>);
<span class="kw">if let </span>Entry::Occupied(o) = map.entry(<span class="string">"poneyland"</span>) {
<span class="comment">// We delete the entry from the map.
</span><span class="macro">assert_eq!</span>(o.remove_entry(), (<span class="string">"poneyland"</span>, <span class="number">12</span>));
}
<span class="macro">assert_eq!</span>(map.contains_key(<span class="string">"poneyland"</span>), <span class="bool-val">false</span>);
<span class="comment">// Now map hold none elements
</span><span class="macro">assert!</span>(map.is_empty());</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.get" class="method"><a class="src rightside" href="../../src/hashbrown/map.rs.html#5334-5336">source</a><h4 class="code-header">pub fn <a href="#method.get" class="fn">get</a>(&amp;self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&amp;V</a></h4></section></summary><div class="docblock"><p>Gets a reference to the value in the entry.</p>
<h5 id="examples-3"><a class="doc-anchor" href="#examples-3">§</a>Examples</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::Entry;
<span class="kw">let </span><span class="kw-2">mut </span>map: HashMap&lt;<span class="kw-2">&amp;</span>str, u32&gt; = HashMap::new();
map.entry(<span class="string">"poneyland"</span>).or_insert(<span class="number">12</span>);
<span class="kw">match </span>map.entry(<span class="string">"poneyland"</span>) {
Entry::Vacant(<span class="kw">_</span>) =&gt; <span class="macro">panic!</span>(),
Entry::Occupied(entry) =&gt; <span class="macro">assert_eq!</span>(entry.get(), <span class="kw-2">&amp;</span><span class="number">12</span>),
}</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.get_mut" class="method"><a class="src rightside" href="../../src/hashbrown/map.rs.html#5366-5368">source</a><h4 class="code-header">pub fn <a href="#method.get_mut" class="fn">get_mut</a>(&amp;mut self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&amp;mut V</a></h4></section></summary><div class="docblock"><p>Gets a mutable reference to the value in the entry.</p>
<p>If you need a reference to the <code>OccupiedEntry</code> which may outlive the
destruction of the <code>Entry</code> value, see <a href="#method.into_mut"><code>into_mut</code></a>.</p>
<h5 id="examples-4"><a class="doc-anchor" href="#examples-4">§</a>Examples</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::Entry;
<span class="kw">let </span><span class="kw-2">mut </span>map: HashMap&lt;<span class="kw-2">&amp;</span>str, u32&gt; = HashMap::new();
map.entry(<span class="string">"poneyland"</span>).or_insert(<span class="number">12</span>);
<span class="macro">assert_eq!</span>(map[<span class="string">"poneyland"</span>], <span class="number">12</span>);
<span class="kw">if let </span>Entry::Occupied(<span class="kw-2">mut </span>o) = map.entry(<span class="string">"poneyland"</span>) {
<span class="kw-2">*</span>o.get_mut() += <span class="number">10</span>;
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>o.get(), <span class="number">22</span>);
<span class="comment">// We can use the same Entry multiple times.
</span><span class="kw-2">*</span>o.get_mut() += <span class="number">2</span>;
}
<span class="macro">assert_eq!</span>(map[<span class="string">"poneyland"</span>], <span class="number">24</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.into_mut" class="method"><a class="src rightside" href="../../src/hashbrown/map.rs.html#5397-5399">source</a><h4 class="code-header">pub fn <a href="#method.into_mut" class="fn">into_mut</a>(self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&amp;'a mut V</a></h4></section></summary><div class="docblock"><p>Converts the OccupiedEntry into a mutable reference to the value in the entry
with a lifetime bound to the map itself.</p>
<p>If you need multiple references to the <code>OccupiedEntry</code>, see <a href="#method.get_mut"><code>get_mut</code></a>.</p>
<h5 id="examples-5"><a class="doc-anchor" href="#examples-5">§</a>Examples</h5>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::hash_map::{Entry, HashMap};
<span class="kw">let </span><span class="kw-2">mut </span>map: HashMap&lt;<span class="kw-2">&amp;</span>str, u32&gt; = HashMap::new();
map.entry(<span class="string">"poneyland"</span>).or_insert(<span class="number">12</span>);
<span class="macro">assert_eq!</span>(map[<span class="string">"poneyland"</span>], <span class="number">12</span>);
<span class="kw">let </span>value: <span class="kw-2">&amp;mut </span>u32;
<span class="kw">match </span>map.entry(<span class="string">"poneyland"</span>) {
Entry::Occupied(entry) =&gt; value = entry.into_mut(),
Entry::Vacant(<span class="kw">_</span>) =&gt; <span class="macro">panic!</span>(),
}
<span class="kw-2">*</span>value += <span class="number">10</span>;
<span class="macro">assert_eq!</span>(map[<span class="string">"poneyland"</span>], <span class="number">22</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.insert" class="method"><a class="src rightside" href="../../src/hashbrown/map.rs.html#5419-5421">source</a><h4 class="code-header">pub fn <a href="#method.insert" class="fn">insert</a>(&amp;mut self, value: V) -&gt; V</h4></section></summary><div class="docblock"><p>Sets the value of the entry, and returns the entrys old value.</p>
<h5 id="examples-6"><a class="doc-anchor" href="#examples-6">§</a>Examples</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::Entry;
<span class="kw">let </span><span class="kw-2">mut </span>map: HashMap&lt;<span class="kw-2">&amp;</span>str, u32&gt; = HashMap::new();
map.entry(<span class="string">"poneyland"</span>).or_insert(<span class="number">12</span>);
<span class="kw">if let </span>Entry::Occupied(<span class="kw-2">mut </span>o) = map.entry(<span class="string">"poneyland"</span>) {
<span class="macro">assert_eq!</span>(o.insert(<span class="number">15</span>), <span class="number">12</span>);
}
<span class="macro">assert_eq!</span>(map[<span class="string">"poneyland"</span>], <span class="number">15</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.remove" class="method"><a class="src rightside" href="../../src/hashbrown/map.rs.html#5447-5449">source</a><h4 class="code-header">pub fn <a href="#method.remove" class="fn">remove</a>(self) -&gt; V</h4></section></summary><div class="docblock"><p>Takes the value out of the entry, and returns it.
Keeps the allocated memory for reuse.</p>
<h5 id="examples-7"><a class="doc-anchor" href="#examples-7">§</a>Examples</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::Entry;
<span class="kw">let </span><span class="kw-2">mut </span>map: HashMap&lt;<span class="kw-2">&amp;</span>str, u32&gt; = HashMap::new();
<span class="comment">// The map is empty
</span><span class="macro">assert!</span>(map.is_empty() &amp;&amp; map.capacity() == <span class="number">0</span>);
map.entry(<span class="string">"poneyland"</span>).or_insert(<span class="number">12</span>);
<span class="kw">if let </span>Entry::Occupied(o) = map.entry(<span class="string">"poneyland"</span>) {
<span class="macro">assert_eq!</span>(o.remove(), <span class="number">12</span>);
}
<span class="macro">assert_eq!</span>(map.contains_key(<span class="string">"poneyland"</span>), <span class="bool-val">false</span>);
<span class="comment">// Now map hold none elements
</span><span class="macro">assert!</span>(map.is_empty());</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.replace_entry" class="method"><a class="src rightside" href="../../src/hashbrown/map.rs.html#5483-5490">source</a><h4 class="code-header">pub fn <a href="#method.replace_entry" class="fn">replace_entry</a>(self, value: V) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.80.0/core/primitive.tuple.html">(K, V)</a></h4></section></summary><div class="docblock"><p>Replaces the entry, returning the old key and value. The new key in the hash map will be
the key used to create this entry.</p>
<h5 id="panics"><a class="doc-anchor" href="#panics">§</a>Panics</h5>
<p>Will panic if this OccupiedEntry was created through <a href="enum.Entry.html#method.insert" title="method hashbrown::hash_map::Entry::insert"><code>Entry::insert</code></a>.</p>
<h5 id="examples-8"><a class="doc-anchor" href="#examples-8">§</a>Examples</h5>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code> <span class="kw">use </span>hashbrown::hash_map::{Entry, HashMap};
<span class="kw">use </span>std::rc::Rc;
<span class="kw">let </span><span class="kw-2">mut </span>map: HashMap&lt;Rc&lt;String&gt;, u32&gt; = HashMap::new();
<span class="kw">let </span>key_one = Rc::new(<span class="string">"Stringthing"</span>.to_string());
<span class="kw">let </span>key_two = Rc::new(<span class="string">"Stringthing"</span>.to_string());
map.insert(key_one.clone(), <span class="number">15</span>);
<span class="macro">assert!</span>(Rc::strong_count(<span class="kw-2">&amp;</span>key_one) == <span class="number">2 </span>&amp;&amp; Rc::strong_count(<span class="kw-2">&amp;</span>key_two) == <span class="number">1</span>);
<span class="kw">match </span>map.entry(key_two.clone()) {
Entry::Occupied(entry) =&gt; {
<span class="kw">let </span>(old_key, old_value): (Rc&lt;String&gt;, u32) = entry.replace_entry(<span class="number">16</span>);
<span class="macro">assert!</span>(Rc::ptr_eq(<span class="kw-2">&amp;</span>key_one, <span class="kw-2">&amp;</span>old_key) &amp;&amp; old_value == <span class="number">15</span>);
}
Entry::Vacant(<span class="kw">_</span>) =&gt; <span class="macro">panic!</span>(),
}
<span class="macro">assert!</span>(Rc::strong_count(<span class="kw-2">&amp;</span>key_one) == <span class="number">1 </span>&amp;&amp; Rc::strong_count(<span class="kw-2">&amp;</span>key_two) == <span class="number">2</span>);
<span class="macro">assert_eq!</span>(map[<span class="kw-2">&amp;</span><span class="string">"Stringthing"</span>.to_owned()], <span class="number">16</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.replace_key" class="method"><a class="src rightside" href="../../src/hashbrown/map.rs.html#5537-5540">source</a><h4 class="code-header">pub fn <a href="#method.replace_key" class="fn">replace_key</a>(self) -&gt; K</h4></section></summary><div class="docblock"><p>Replaces the key in the hash map with the key used to create this entry.</p>
<h5 id="panics-1"><a class="doc-anchor" href="#panics-1">§</a>Panics</h5>
<p>Will panic if this OccupiedEntry was created through <a href="enum.Entry.html#method.insert" title="method hashbrown::hash_map::Entry::insert"><code>Entry::insert</code></a>.</p>
<h5 id="examples-9"><a class="doc-anchor" href="#examples-9">§</a>Examples</h5>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>hashbrown::hash_map::{Entry, HashMap};
<span class="kw">use </span>std::rc::Rc;
<span class="kw">let </span><span class="kw-2">mut </span>map: HashMap&lt;Rc&lt;String&gt;, usize&gt; = HashMap::with_capacity(<span class="number">6</span>);
<span class="kw">let </span><span class="kw-2">mut </span>keys_one: Vec&lt;Rc&lt;String&gt;&gt; = Vec::with_capacity(<span class="number">6</span>);
<span class="kw">let </span><span class="kw-2">mut </span>keys_two: Vec&lt;Rc&lt;String&gt;&gt; = Vec::with_capacity(<span class="number">6</span>);
<span class="kw">for </span>(value, key) <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>].into_iter().enumerate() {
<span class="kw">let </span>rc_key = Rc::new(key.to_owned());
keys_one.push(rc_key.clone());
map.insert(rc_key.clone(), value);
keys_two.push(Rc::new(key.to_owned()));
}
<span class="macro">assert!</span>(
keys_one.iter().all(|key| Rc::strong_count(key) == <span class="number">2</span>)
&amp;&amp; keys_two.iter().all(|key| Rc::strong_count(key) == <span class="number">1</span>)
);
reclaim_memory(<span class="kw-2">&amp;mut </span>map, <span class="kw-2">&amp;</span>keys_two);
<span class="macro">assert!</span>(
keys_one.iter().all(|key| Rc::strong_count(key) == <span class="number">1</span>)
&amp;&amp; keys_two.iter().all(|key| Rc::strong_count(key) == <span class="number">2</span>)
);
<span class="kw">fn </span>reclaim_memory(map: <span class="kw-2">&amp;mut </span>HashMap&lt;Rc&lt;String&gt;, usize&gt;, keys: <span class="kw-2">&amp;</span>[Rc&lt;String&gt;]) {
<span class="kw">for </span>key <span class="kw">in </span>keys {
<span class="kw">if let </span>Entry::Occupied(entry) = map.entry(key.clone()) {
<span class="comment">// Replaces the entry's key with our version of it in `keys`.
</span>entry.replace_key();
}
}
}</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.replace_entry_with" class="method"><a class="src rightside" href="../../src/hashbrown/map.rs.html#5591-5619">source</a><h4 class="code-header">pub fn <a href="#method.replace_entry_with" class="fn">replace_entry_with</a>&lt;F&gt;(self, f: F) -&gt; <a class="enum" href="enum.Entry.html" title="enum hashbrown::hash_map::Entry">Entry</a>&lt;'a, K, V, S, A&gt;<div class="where">where
F: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/ops/function/trait.FnOnce.html" title="trait core::ops::function::FnOnce">FnOnce</a>(<a class="primitive" href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&amp;K</a>, V) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.80.0/core/option/enum.Option.html" title="enum core::option::Option">Option</a>&lt;V&gt;,</div></h4></section></summary><div class="docblock"><p>Provides shared access to the key and owned access to the value of
the entry and allows to replace or remove it based on the
value of the returned option.</p>
<h5 id="examples-10"><a class="doc-anchor" href="#examples-10">§</a>Examples</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::Entry;
<span class="kw">let </span><span class="kw-2">mut </span>map: HashMap&lt;<span class="kw-2">&amp;</span>str, u32&gt; = HashMap::new();
map.insert(<span class="string">"poneyland"</span>, <span class="number">42</span>);
<span class="kw">let </span>entry = <span class="kw">match </span>map.entry(<span class="string">"poneyland"</span>) {
Entry::Occupied(e) =&gt; {
e.replace_entry_with(|k, v| {
<span class="macro">assert_eq!</span>(k, <span class="kw-2">&amp;</span><span class="string">"poneyland"</span>);
<span class="macro">assert_eq!</span>(v, <span class="number">42</span>);
<span class="prelude-val">Some</span>(v + <span class="number">1</span>)
})
}
Entry::Vacant(<span class="kw">_</span>) =&gt; <span class="macro">panic!</span>(),
};
<span class="kw">match </span>entry {
Entry::Occupied(e) =&gt; {
<span class="macro">assert_eq!</span>(e.key(), <span class="kw-2">&amp;</span><span class="string">"poneyland"</span>);
<span class="macro">assert_eq!</span>(e.get(), <span class="kw-2">&amp;</span><span class="number">43</span>);
}
Entry::Vacant(<span class="kw">_</span>) =&gt; <span class="macro">panic!</span>(),
}
<span class="macro">assert_eq!</span>(map[<span class="string">"poneyland"</span>], <span class="number">43</span>);
<span class="kw">let </span>entry = <span class="kw">match </span>map.entry(<span class="string">"poneyland"</span>) {
Entry::Occupied(e) =&gt; e.replace_entry_with(|_k, _v| <span class="prelude-val">None</span>),
Entry::Vacant(<span class="kw">_</span>) =&gt; <span class="macro">panic!</span>(),
};
<span class="kw">match </span>entry {
Entry::Vacant(e) =&gt; {
<span class="macro">assert_eq!</span>(e.key(), <span class="kw-2">&amp;</span><span class="string">"poneyland"</span>);
}
Entry::Occupied(<span class="kw">_</span>) =&gt; <span class="macro">panic!</span>(),
}
<span class="macro">assert!</span>(!map.contains_key(<span class="string">"poneyland"</span>));</code></pre></div>
</div></details></div></details></div><h2 id="trait-implementations" class="section-header">Trait Implementations<a href="#trait-implementations" class="anchor">§</a></h2><div id="trait-implementations-list"><details class="toggle implementors-toggle" open><summary><section id="impl-Debug-for-OccupiedEntry%3C'_,+K,+V,+S,+A%3E" class="impl"><a class="src rightside" href="../../src/hashbrown/map.rs.html#4274-4281">source</a><a href="#impl-Debug-for-OccupiedEntry%3C'_,+K,+V,+S,+A%3E" class="anchor">§</a><h3 class="code-header">impl&lt;K: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a>, V: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a>, S, A: Allocator&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> for <a class="struct" href="struct.OccupiedEntry.html" title="struct hashbrown::hash_map::OccupiedEntry">OccupiedEntry</a>&lt;'_, K, V, S, A&gt;</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.fmt" class="method trait-impl"><a class="src rightside" href="../../src/hashbrown/map.rs.html#4275-4280">source</a><a href="#method.fmt" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Debug.html#tymethod.fmt" class="fn">fmt</a>(&amp;self, f: &amp;mut <a class="struct" href="https://doc.rust-lang.org/1.80.0/core/fmt/struct.Formatter.html" title="struct core::fmt::Formatter">Formatter</a>&lt;'_&gt;) -&gt; <a class="type" href="https://doc.rust-lang.org/1.80.0/core/fmt/type.Result.html" title="type core::fmt::Result">Result</a></h4></section></summary><div class='docblock'>Formats the value using the given formatter. <a href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Debug.html#tymethod.fmt">Read more</a></div></details></div></details><section id="impl-Send-for-OccupiedEntry%3C'_,+K,+V,+S,+A%3E" class="impl"><a class="src rightside" href="../../src/hashbrown/map.rs.html#4257-4264">source</a><a href="#impl-Send-for-OccupiedEntry%3C'_,+K,+V,+S,+A%3E" class="anchor">§</a><h3 class="code-header">impl&lt;K, V, S, A&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> for <a class="struct" href="struct.OccupiedEntry.html" title="struct hashbrown::hash_map::OccupiedEntry">OccupiedEntry</a>&lt;'_, K, V, S, A&gt;<div class="where">where
K: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a>,
V: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a>,
S: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a>,
A: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> + Allocator,</div></h3></section><section id="impl-Sync-for-OccupiedEntry%3C'_,+K,+V,+S,+A%3E" class="impl"><a class="src rightside" href="../../src/hashbrown/map.rs.html#4265-4272">source</a><a href="#impl-Sync-for-OccupiedEntry%3C'_,+K,+V,+S,+A%3E" class="anchor">§</a><h3 class="code-header">impl&lt;K, V, S, A&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> for <a class="struct" href="struct.OccupiedEntry.html" title="struct hashbrown::hash_map::OccupiedEntry">OccupiedEntry</a>&lt;'_, K, V, S, A&gt;<div class="where">where
K: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a>,
V: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a>,
S: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a>,
A: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> + Allocator,</div></h3></section></div><h2 id="synthetic-implementations" class="section-header">Auto Trait Implementations<a href="#synthetic-implementations" class="anchor">§</a></h2><div id="synthetic-implementations-list"><section id="impl-Freeze-for-OccupiedEntry%3C'a,+K,+V,+S,+A%3E" class="impl"><a href="#impl-Freeze-for-OccupiedEntry%3C'a,+K,+V,+S,+A%3E" class="anchor">§</a><h3 class="code-header">impl&lt;'a, K, V, S, A&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Freeze.html" title="trait core::marker::Freeze">Freeze</a> for <a class="struct" href="struct.OccupiedEntry.html" title="struct hashbrown::hash_map::OccupiedEntry">OccupiedEntry</a>&lt;'a, K, V, S, A&gt;<div class="where">where
K: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Freeze.html" title="trait core::marker::Freeze">Freeze</a>,</div></h3></section><section id="impl-RefUnwindSafe-for-OccupiedEntry%3C'a,+K,+V,+S,+A%3E" class="impl"><a href="#impl-RefUnwindSafe-for-OccupiedEntry%3C'a,+K,+V,+S,+A%3E" class="anchor">§</a><h3 class="code-header">impl&lt;'a, K, V, S, A&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/panic/unwind_safe/trait.RefUnwindSafe.html" title="trait core::panic::unwind_safe::RefUnwindSafe">RefUnwindSafe</a> for <a class="struct" href="struct.OccupiedEntry.html" title="struct hashbrown::hash_map::OccupiedEntry">OccupiedEntry</a>&lt;'a, K, V, S, A&gt;<div class="where">where
K: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/panic/unwind_safe/trait.RefUnwindSafe.html" title="trait core::panic::unwind_safe::RefUnwindSafe">RefUnwindSafe</a>,
S: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/panic/unwind_safe/trait.RefUnwindSafe.html" title="trait core::panic::unwind_safe::RefUnwindSafe">RefUnwindSafe</a>,
A: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/panic/unwind_safe/trait.RefUnwindSafe.html" title="trait core::panic::unwind_safe::RefUnwindSafe">RefUnwindSafe</a>,
V: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/panic/unwind_safe/trait.RefUnwindSafe.html" title="trait core::panic::unwind_safe::RefUnwindSafe">RefUnwindSafe</a>,</div></h3></section><section id="impl-Unpin-for-OccupiedEntry%3C'a,+K,+V,+S,+A%3E" class="impl"><a href="#impl-Unpin-for-OccupiedEntry%3C'a,+K,+V,+S,+A%3E" class="anchor">§</a><h3 class="code-header">impl&lt;'a, K, V, S, A&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Unpin.html" title="trait core::marker::Unpin">Unpin</a> for <a class="struct" href="struct.OccupiedEntry.html" title="struct hashbrown::hash_map::OccupiedEntry">OccupiedEntry</a>&lt;'a, K, V, S, A&gt;<div class="where">where
K: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Unpin.html" title="trait core::marker::Unpin">Unpin</a>,</div></h3></section><section id="impl-UnwindSafe-for-OccupiedEntry%3C'a,+K,+V,+S,+A%3E" class="impl"><a href="#impl-UnwindSafe-for-OccupiedEntry%3C'a,+K,+V,+S,+A%3E" class="anchor">§</a><h3 class="code-header">impl&lt;'a, K, V, S = <a class="enum" href="enum.DefaultHashBuilder.html" title="enum hashbrown::hash_map::DefaultHashBuilder">DefaultHashBuilder</a>, A = Global&gt; !<a class="trait" href="https://doc.rust-lang.org/1.80.0/core/panic/unwind_safe/trait.UnwindSafe.html" title="trait core::panic::unwind_safe::UnwindSafe">UnwindSafe</a> for <a class="struct" href="struct.OccupiedEntry.html" title="struct hashbrown::hash_map::OccupiedEntry">OccupiedEntry</a>&lt;'a, K, V, S, A&gt;</h3></section></div><h2 id="blanket-implementations" class="section-header">Blanket Implementations<a href="#blanket-implementations" class="anchor">§</a></h2><div id="blanket-implementations-list"><details class="toggle implementors-toggle"><summary><section id="impl-Any-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/any.rs.html#140">source</a><a href="#impl-Any-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/any/trait.Any.html" title="trait core::any::Any">Any</a> for T<div class="where">where
T: 'static + ?<a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.type_id" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/any.rs.html#141">source</a><a href="#method.type_id" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/any/trait.Any.html#tymethod.type_id" class="fn">type_id</a>(&amp;self) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.80.0/core/any/struct.TypeId.html" title="struct core::any::TypeId">TypeId</a></h4></section></summary><div class='docblock'>Gets the <code>TypeId</code> of <code>self</code>. <a href="https://doc.rust-lang.org/1.80.0/core/any/trait.Any.html#tymethod.type_id">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-Borrow%3CT%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/borrow.rs.html#208">source</a><a href="#impl-Borrow%3CT%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/borrow/trait.Borrow.html" title="trait core::borrow::Borrow">Borrow</a>&lt;T&gt; for T<div class="where">where
T: ?<a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.borrow" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/borrow.rs.html#210">source</a><a href="#method.borrow" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/borrow/trait.Borrow.html#tymethod.borrow" class="fn">borrow</a>(&amp;self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&amp;T</a></h4></section></summary><div class='docblock'>Immutably borrows from an owned value. <a href="https://doc.rust-lang.org/1.80.0/core/borrow/trait.Borrow.html#tymethod.borrow">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-BorrowMut%3CT%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/borrow.rs.html#216">source</a><a href="#impl-BorrowMut%3CT%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/borrow/trait.BorrowMut.html" title="trait core::borrow::BorrowMut">BorrowMut</a>&lt;T&gt; for T<div class="where">where
T: ?<a class="trait" href="https://doc.rust-lang.org/1.80.0/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.borrow_mut" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/borrow.rs.html#217">source</a><a href="#method.borrow_mut" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/borrow/trait.BorrowMut.html#tymethod.borrow_mut" class="fn">borrow_mut</a>(&amp;mut self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.80.0/core/primitive.reference.html">&amp;mut T</a></h4></section></summary><div class='docblock'>Mutably borrows from an owned value. <a href="https://doc.rust-lang.org/1.80.0/core/borrow/trait.BorrowMut.html#tymethod.borrow_mut">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-From%3CT%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#765">source</a><a href="#impl-From%3CT%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;T&gt; for T</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.from" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#768">source</a><a href="#method.from" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html#tymethod.from" class="fn">from</a>(t: T) -&gt; T</h4></section></summary><div class="docblock"><p>Returns the argument unchanged.</p>
</div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-Into%3CU%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#748-750">source</a><a href="#impl-Into%3CU%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T, U&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.Into.html" title="trait core::convert::Into">Into</a>&lt;U&gt; for T<div class="where">where
U: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;T&gt;,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.into" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#758">source</a><a href="#method.into" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.Into.html#tymethod.into" class="fn">into</a>(self) -&gt; 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><a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;T&gt; for U</code> chooses to do.</p>
</div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-TryFrom%3CU%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#805-807">source</a><a href="#impl-TryFrom%3CU%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T, U&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;U&gt; for T<div class="where">where
U: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.Into.html" title="trait core::convert::Into">Into</a>&lt;T&gt;,</div></h3></section></summary><div class="impl-items"><details class="toggle" open><summary><section id="associatedtype.Error" class="associatedtype trait-impl"><a href="#associatedtype.Error" class="anchor">§</a><h4 class="code-header">type <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html#associatedtype.Error" class="associatedtype">Error</a> = <a class="enum" href="https://doc.rust-lang.org/1.80.0/core/convert/enum.Infallible.html" title="enum core::convert::Infallible">Infallible</a></h4></section></summary><div class='docblock'>The type returned in the event of a conversion error.</div></details><details class="toggle method-toggle" open><summary><section id="method.try_from" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#812">source</a><a href="#method.try_from" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html#tymethod.try_from" class="fn">try_from</a>(value: U) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.80.0/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;T, &lt;T as <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;U&gt;&gt;::<a class="associatedtype" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a>&gt;</h4></section></summary><div class='docblock'>Performs the conversion.</div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-TryInto%3CU%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#790-792">source</a><a href="#impl-TryInto%3CU%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T, U&gt; <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryInto.html" title="trait core::convert::TryInto">TryInto</a>&lt;U&gt; for T<div class="where">where
U: <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;T&gt;,</div></h3></section></summary><div class="impl-items"><details class="toggle" open><summary><section id="associatedtype.Error-1" class="associatedtype trait-impl"><a href="#associatedtype.Error-1" class="anchor">§</a><h4 class="code-header">type <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryInto.html#associatedtype.Error" class="associatedtype">Error</a> = &lt;U as <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;T&gt;&gt;::<a class="associatedtype" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a></h4></section></summary><div class='docblock'>The type returned in the event of a conversion error.</div></details><details class="toggle method-toggle" open><summary><section id="method.try_into" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.80.0/src/core/convert/mod.rs.html#797">source</a><a href="#method.try_into" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryInto.html#tymethod.try_into" class="fn">try_into</a>(self) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.80.0/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;U, &lt;U as <a class="trait" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;T&gt;&gt;::<a class="associatedtype" href="https://doc.rust-lang.org/1.80.0/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a>&gt;</h4></section></summary><div class='docblock'>Performs the conversion.</div></details></div></details></div></section></div></main></body></html>