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<p class='location'>Struct OccupiedEntry</p><div class="sidebar-elems"><div class="block items"><a class="sidebar-title" href="#methods">Methods</a><div class="sidebar-links"><a href="#method.key">key</a><a href="#method.remove_entry">remove_entry</a><a href="#method.get">get</a><a href="#method.get_mut">get_mut</a><a href="#method.into_mut">into_mut</a><a href="#method.insert">insert</a><a href="#method.remove">remove</a><a href="#method.replace_entry">replace_entry</a><a href="#method.replace_key">replace_key</a></div><a class="sidebar-title" href="#implementations">Trait Implementations</a><div class="sidebar-links"><a href="#impl-Debug">Debug</a></div></div><p class='location'><a href='../../index.html'>std</a>::<wbr><a href='../index.html'>collections</a>::<wbr><a href='index.html'>hash_map</a></p><script>window.sidebarCurrent = {name: 'OccupiedEntry', ty: 'struct', relpath: ''};</script><script defer src="sidebar-items.js"></script></div>
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<h1 class='fqn'><span class='in-band'>Struct <a href='../../index.html'>std</a>::<wbr><a href='../index.html'>collections</a>::<wbr><a href='index.html'>hash_map</a>::<wbr><a class="struct" href=''>OccupiedEntry</a></span><span class='out-of-band'><span class='since' title='Stable since Rust version 1.0.0'>1.0.0</span><span id='render-detail'>
<a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">
[<span class='inner'>−</span>]
</a>
</span><a class='srclink' href='../../../src/std/collections/hash/map.rs.html#1616-1619' title='goto source code'>[src]</a></span></h1>
<pre class='rust struct'>pub struct OccupiedEntry<'a, K: 'a, V: 'a> { /* fields omitted */ }</pre><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>
</div>
<h2 id='methods' class='small-section-header'>
Methods<a href='#methods' class='anchor'></a>
</h2>
<h3 id='impl' class='impl'><span class='in-band'><code>impl<'a, K, V> <a class="struct" href="../../../std/collections/hash_map/struct.OccupiedEntry.html" title="struct std::collections::hash_map::OccupiedEntry">OccupiedEntry</a><'a, K, V></code><a href='#impl' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/std/collections/hash/map.rs.html#2126-2348' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.key' class="method"><div class="important-traits"><div class='tooltip'>ⓘ<span class='tooltiptext'>Important traits for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>I</span></div><div class="content hidden"><h3 class="important">Important traits for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>I</h3><code class="content"><span class="where fmt-newline">impl<'a, I> <a class="trait" href="../../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>I <span class="where fmt-newline">where<br> I: <a class="trait" href="../../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> + ?<a class="trait" href="../../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></span><span class="where fmt-newline"> type <a href='../../../std/iter/trait.Iterator.html#associatedtype.Item' class="type">Item</a> = <I as <a class="trait" href="../../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a>>::<a class="type" href="../../../std/iter/trait.Iterator.html#associatedtype.Item" title="type std::iter::Iterator::Item">Item</a>;</span><span class="where fmt-newline">impl<'a, R: <a class="trait" href="../../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> + ?<a class="trait" href="../../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>> <a class="trait" href="../../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>R</span><span class="where fmt-newline">impl<'a, W: <a class="trait" href="../../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> + ?<a class="trait" href="../../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>> <a class="trait" href="../../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>W</span></code></div></div><span id='key.v' class='invisible'><code>pub fn <a href='#method.key' class='fnname'>key</a>(&self) -> <a class="primitive" href="../../primitive.reference.html">&</a>K</code></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.10.0'>1.10.0</div><a class='srclink' href='../../../src/std/collections/hash/map.rs.html#2139-2141' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Gets a reference to the key in the entry.</p>
<h1 id="examples" class="section-header"><a href="#examples">Examples</a></h1>
<pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">HashMap</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">map</span>: <span class="ident">HashMap</span><span class="op"><</span><span class="kw-2">&</span><span class="ident">str</span>, <span class="ident">u32</span><span class="op">></span> <span class="op">=</span> <span class="ident">HashMap</span>::<span class="ident">new</span>();
<span class="ident">map</span>.<span class="ident">entry</span>(<span class="string">"poneyland"</span>).<span class="ident">or_insert</span>(<span class="number">12</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">map</span>.<span class="ident">entry</span>(<span class="string">"poneyland"</span>).<span class="ident">key</span>(), <span class="kw-2">&</span><span class="string">"poneyland"</span>);<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Acollections%3A%3AHashMap%3B%0A%0Alet%20mut%20map%3A%20HashMap%3C%26str%2C%20u32%3E%20%3D%20HashMap%3A%3Anew()%3B%0Amap.entry(%22poneyland%22).or_insert(12)%3B%0Aassert_eq!(map.entry(%22poneyland%22).key()%2C%20%26%22poneyland%22)%3B%0A%7D">Run</a></pre>
</div><h4 id='method.remove_entry' class="method"><span id='remove_entry.v' class='invisible'><code>pub fn <a href='#method.remove_entry' class='fnname'>remove_entry</a>(self) -> <a class="primitive" href="../../primitive.tuple.html">(</a>K, V<a class="primitive" href="../../primitive.tuple.html">)</a></code></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.12.0'>1.12.0</div><a class='srclink' href='../../../src/std/collections/hash/map.rs.html#2162-2165' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Take the ownership of the key and value from the map.</p>
<h1 id="examples-1" class="section-header"><a href="#examples-1">Examples</a></h1>
<pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">HashMap</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">hash_map</span>::<span class="ident">Entry</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">map</span>: <span class="ident">HashMap</span><span class="op"><</span><span class="kw-2">&</span><span class="ident">str</span>, <span class="ident">u32</span><span class="op">></span> <span class="op">=</span> <span class="ident">HashMap</span>::<span class="ident">new</span>();
<span class="ident">map</span>.<span class="ident">entry</span>(<span class="string">"poneyland"</span>).<span class="ident">or_insert</span>(<span class="number">12</span>);
<span class="kw">if</span> <span class="kw">let</span> <span class="ident">Entry</span>::<span class="ident">Occupied</span>(<span class="ident">o</span>) <span class="op">=</span> <span class="ident">map</span>.<span class="ident">entry</span>(<span class="string">"poneyland"</span>) {
<span class="comment">// We delete the entry from the map.</span>
<span class="ident">o</span>.<span class="ident">remove_entry</span>();
}
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">map</span>.<span class="ident">contains_key</span>(<span class="string">"poneyland"</span>), <span class="bool-val">false</span>);<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Acollections%3A%3AHashMap%3B%0Ause%20std%3A%3Acollections%3A%3Ahash_map%3A%3AEntry%3B%0A%0Alet%20mut%20map%3A%20HashMap%3C%26str%2C%20u32%3E%20%3D%20HashMap%3A%3Anew()%3B%0Amap.entry(%22poneyland%22).or_insert(12)%3B%0A%0Aif%20let%20Entry%3A%3AOccupied(o)%20%3D%20map.entry(%22poneyland%22)%20%7B%0A%20%20%20%20%2F%2F%20We%20delete%20the%20entry%20from%20the%20map.%0A%20%20%20%20o.remove_entry()%3B%0A%7D%0A%0Aassert_eq!(map.contains_key(%22poneyland%22)%2C%20false)%3B%0A%7D">Run</a></pre>
</div><h4 id='method.get' class="method"><div class="important-traits"><div class='tooltip'>ⓘ<span class='tooltiptext'>Important traits for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>I</span></div><div class="content hidden"><h3 class="important">Important traits for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>I</h3><code class="content"><span class="where fmt-newline">impl<'a, I> <a class="trait" href="../../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>I <span class="where fmt-newline">where<br> I: <a class="trait" href="../../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> + ?<a class="trait" href="../../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></span><span class="where fmt-newline"> type <a href='../../../std/iter/trait.Iterator.html#associatedtype.Item' class="type">Item</a> = <I as <a class="trait" href="../../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a>>::<a class="type" href="../../../std/iter/trait.Iterator.html#associatedtype.Item" title="type std::iter::Iterator::Item">Item</a>;</span><span class="where fmt-newline">impl<'a, R: <a class="trait" href="../../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> + ?<a class="trait" href="../../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>> <a class="trait" href="../../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>R</span><span class="where fmt-newline">impl<'a, W: <a class="trait" href="../../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> + ?<a class="trait" href="../../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>> <a class="trait" href="../../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>W</span></code></div></div><span id='get.v' class='invisible'><code>pub fn <a href='#method.get' class='fnname'>get</a>(&self) -> <a class="primitive" href="../../primitive.reference.html">&</a>V</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/std/collections/hash/map.rs.html#2183-2185' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Gets a reference to the value in the entry.</p>
<h1 id="examples-2" class="section-header"><a href="#examples-2">Examples</a></h1>
<pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">HashMap</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">hash_map</span>::<span class="ident">Entry</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">map</span>: <span class="ident">HashMap</span><span class="op"><</span><span class="kw-2">&</span><span class="ident">str</span>, <span class="ident">u32</span><span class="op">></span> <span class="op">=</span> <span class="ident">HashMap</span>::<span class="ident">new</span>();
<span class="ident">map</span>.<span class="ident">entry</span>(<span class="string">"poneyland"</span>).<span class="ident">or_insert</span>(<span class="number">12</span>);
<span class="kw">if</span> <span class="kw">let</span> <span class="ident">Entry</span>::<span class="ident">Occupied</span>(<span class="ident">o</span>) <span class="op">=</span> <span class="ident">map</span>.<span class="ident">entry</span>(<span class="string">"poneyland"</span>) {
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">o</span>.<span class="ident">get</span>(), <span class="kw-2">&</span><span class="number">12</span>);
}<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Acollections%3A%3AHashMap%3B%0Ause%20std%3A%3Acollections%3A%3Ahash_map%3A%3AEntry%3B%0A%0Alet%20mut%20map%3A%20HashMap%3C%26str%2C%20u32%3E%20%3D%20HashMap%3A%3Anew()%3B%0Amap.entry(%22poneyland%22).or_insert(12)%3B%0A%0Aif%20let%20Entry%3A%3AOccupied(o)%20%3D%20map.entry(%22poneyland%22)%20%7B%0A%20%20%20%20assert_eq!(o.get()%2C%20%2612)%3B%0A%7D%0A%7D">Run</a></pre>
</div><h4 id='method.get_mut' class="method"><div class="important-traits"><div class='tooltip'>ⓘ<span class='tooltiptext'>Important traits for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>I</span></div><div class="content hidden"><h3 class="important">Important traits for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>I</h3><code class="content"><span class="where fmt-newline">impl<'a, I> <a class="trait" href="../../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>I <span class="where fmt-newline">where<br> I: <a class="trait" href="../../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> + ?<a class="trait" href="../../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></span><span class="where fmt-newline"> type <a href='../../../std/iter/trait.Iterator.html#associatedtype.Item' class="type">Item</a> = <I as <a class="trait" href="../../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a>>::<a class="type" href="../../../std/iter/trait.Iterator.html#associatedtype.Item" title="type std::iter::Iterator::Item">Item</a>;</span><span class="where fmt-newline">impl<'a, R: <a class="trait" href="../../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> + ?<a class="trait" href="../../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>> <a class="trait" href="../../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>R</span><span class="where fmt-newline">impl<'a, W: <a class="trait" href="../../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> + ?<a class="trait" href="../../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>> <a class="trait" href="../../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>W</span></code></div></div><span id='get_mut.v' class='invisible'><code>pub fn <a href='#method.get_mut' class='fnname'>get_mut</a>(&mut self) -> <a class="primitive" href="../../primitive.reference.html">&mut </a>V</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/std/collections/hash/map.rs.html#2206-2208' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Gets a mutable reference to the value in the entry.</p>
<h1 id="examples-3" class="section-header"><a href="#examples-3">Examples</a></h1>
<pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">HashMap</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">hash_map</span>::<span class="ident">Entry</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">map</span>: <span class="ident">HashMap</span><span class="op"><</span><span class="kw-2">&</span><span class="ident">str</span>, <span class="ident">u32</span><span class="op">></span> <span class="op">=</span> <span class="ident">HashMap</span>::<span class="ident">new</span>();
<span class="ident">map</span>.<span class="ident">entry</span>(<span class="string">"poneyland"</span>).<span class="ident">or_insert</span>(<span class="number">12</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">map</span>[<span class="string">"poneyland"</span>], <span class="number">12</span>);
<span class="kw">if</span> <span class="kw">let</span> <span class="ident">Entry</span>::<span class="ident">Occupied</span>(<span class="kw-2">mut</span> <span class="ident">o</span>) <span class="op">=</span> <span class="ident">map</span>.<span class="ident">entry</span>(<span class="string">"poneyland"</span>) {
<span class="kw-2">*</span><span class="ident">o</span>.<span class="ident">get_mut</span>() <span class="op">+=</span> <span class="number">10</span>;
}
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">map</span>[<span class="string">"poneyland"</span>], <span class="number">22</span>);<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Acollections%3A%3AHashMap%3B%0Ause%20std%3A%3Acollections%3A%3Ahash_map%3A%3AEntry%3B%0A%0Alet%20mut%20map%3A%20HashMap%3C%26str%2C%20u32%3E%20%3D%20HashMap%3A%3Anew()%3B%0Amap.entry(%22poneyland%22).or_insert(12)%3B%0A%0Aassert_eq!(map%5B%22poneyland%22%5D%2C%2012)%3B%0Aif%20let%20Entry%3A%3AOccupied(mut%20o)%20%3D%20map.entry(%22poneyland%22)%20%7B%0A%20%20%20%20%20*o.get_mut()%20%2B%3D%2010%3B%0A%7D%0A%0Aassert_eq!(map%5B%22poneyland%22%5D%2C%2022)%3B%0A%7D">Run</a></pre>
</div><h4 id='method.into_mut' class="method"><div class="important-traits"><div class='tooltip'>ⓘ<span class='tooltiptext'>Important traits for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>I</span></div><div class="content hidden"><h3 class="important">Important traits for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>I</h3><code class="content"><span class="where fmt-newline">impl<'a, I> <a class="trait" href="../../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>I <span class="where fmt-newline">where<br> I: <a class="trait" href="../../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a> + ?<a class="trait" href="../../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>, </span></span><span class="where fmt-newline"> type <a href='../../../std/iter/trait.Iterator.html#associatedtype.Item' class="type">Item</a> = <I as <a class="trait" href="../../../std/iter/trait.Iterator.html" title="trait std::iter::Iterator">Iterator</a>>::<a class="type" href="../../../std/iter/trait.Iterator.html#associatedtype.Item" title="type std::iter::Iterator::Item">Item</a>;</span><span class="where fmt-newline">impl<'a, R: <a class="trait" href="../../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> + ?<a class="trait" href="../../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>> <a class="trait" href="../../../std/io/trait.Read.html" title="trait std::io::Read">Read</a> for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>R</span><span class="where fmt-newline">impl<'a, W: <a class="trait" href="../../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> + ?<a class="trait" href="../../../std/marker/trait.Sized.html" title="trait std::marker::Sized">Sized</a>> <a class="trait" href="../../../std/io/trait.Write.html" title="trait std::io::Write">Write</a> for <a class="primitive" href="../../primitive.reference.html">&'a mut </a>W</span></code></div></div><span id='into_mut.v' class='invisible'><code>pub fn <a href='#method.into_mut' class='fnname'>into_mut</a>(self) -> <a class="primitive" href="../../primitive.reference.html">&'a mut </a>V</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/std/collections/hash/map.rs.html#2230-2232' title='goto source code'>[src]</a></span></h4>
<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>
<h1 id="examples-4" class="section-header"><a href="#examples-4">Examples</a></h1>
<pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">HashMap</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">hash_map</span>::<span class="ident">Entry</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">map</span>: <span class="ident">HashMap</span><span class="op"><</span><span class="kw-2">&</span><span class="ident">str</span>, <span class="ident">u32</span><span class="op">></span> <span class="op">=</span> <span class="ident">HashMap</span>::<span class="ident">new</span>();
<span class="ident">map</span>.<span class="ident">entry</span>(<span class="string">"poneyland"</span>).<span class="ident">or_insert</span>(<span class="number">12</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">map</span>[<span class="string">"poneyland"</span>], <span class="number">12</span>);
<span class="kw">if</span> <span class="kw">let</span> <span class="ident">Entry</span>::<span class="ident">Occupied</span>(<span class="ident">o</span>) <span class="op">=</span> <span class="ident">map</span>.<span class="ident">entry</span>(<span class="string">"poneyland"</span>) {
<span class="kw-2">*</span><span class="ident">o</span>.<span class="ident">into_mut</span>() <span class="op">+=</span> <span class="number">10</span>;
}
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">map</span>[<span class="string">"poneyland"</span>], <span class="number">22</span>);<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Acollections%3A%3AHashMap%3B%0Ause%20std%3A%3Acollections%3A%3Ahash_map%3A%3AEntry%3B%0A%0Alet%20mut%20map%3A%20HashMap%3C%26str%2C%20u32%3E%20%3D%20HashMap%3A%3Anew()%3B%0Amap.entry(%22poneyland%22).or_insert(12)%3B%0A%0Aassert_eq!(map%5B%22poneyland%22%5D%2C%2012)%3B%0Aif%20let%20Entry%3A%3AOccupied(o)%20%3D%20map.entry(%22poneyland%22)%20%7B%0A%20%20%20%20*o.into_mut()%20%2B%3D%2010%3B%0A%7D%0A%0Aassert_eq!(map%5B%22poneyland%22%5D%2C%2022)%3B%0A%7D">Run</a></pre>
</div><h4 id='method.insert' class="method"><span id='insert.v' class='invisible'><code>pub fn <a href='#method.insert' class='fnname'>insert</a>(&mut self, value: V) -> V</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/std/collections/hash/map.rs.html#2252-2256' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Sets the value of the entry, and returns the entry's old value.</p>
<h1 id="examples-5" class="section-header"><a href="#examples-5">Examples</a></h1>
<pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">HashMap</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">hash_map</span>::<span class="ident">Entry</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">map</span>: <span class="ident">HashMap</span><span class="op"><</span><span class="kw-2">&</span><span class="ident">str</span>, <span class="ident">u32</span><span class="op">></span> <span class="op">=</span> <span class="ident">HashMap</span>::<span class="ident">new</span>();
<span class="ident">map</span>.<span class="ident">entry</span>(<span class="string">"poneyland"</span>).<span class="ident">or_insert</span>(<span class="number">12</span>);
<span class="kw">if</span> <span class="kw">let</span> <span class="ident">Entry</span>::<span class="ident">Occupied</span>(<span class="kw-2">mut</span> <span class="ident">o</span>) <span class="op">=</span> <span class="ident">map</span>.<span class="ident">entry</span>(<span class="string">"poneyland"</span>) {
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">o</span>.<span class="ident">insert</span>(<span class="number">15</span>), <span class="number">12</span>);
}
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">map</span>[<span class="string">"poneyland"</span>], <span class="number">15</span>);<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Acollections%3A%3AHashMap%3B%0Ause%20std%3A%3Acollections%3A%3Ahash_map%3A%3AEntry%3B%0A%0Alet%20mut%20map%3A%20HashMap%3C%26str%2C%20u32%3E%20%3D%20HashMap%3A%3Anew()%3B%0Amap.entry(%22poneyland%22).or_insert(12)%3B%0A%0Aif%20let%20Entry%3A%3AOccupied(mut%20o)%20%3D%20map.entry(%22poneyland%22)%20%7B%0A%20%20%20%20assert_eq!(o.insert(15)%2C%2012)%3B%0A%7D%0A%0Aassert_eq!(map%5B%22poneyland%22%5D%2C%2015)%3B%0A%7D">Run</a></pre>
</div><h4 id='method.remove' class="method"><span id='remove.v' class='invisible'><code>pub fn <a href='#method.remove' class='fnname'>remove</a>(self) -> V</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/std/collections/hash/map.rs.html#2276-2278' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Takes the value out of the entry, and returns it.</p>
<h1 id="examples-6" class="section-header"><a href="#examples-6">Examples</a></h1>
<pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">HashMap</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">hash_map</span>::<span class="ident">Entry</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">map</span>: <span class="ident">HashMap</span><span class="op"><</span><span class="kw-2">&</span><span class="ident">str</span>, <span class="ident">u32</span><span class="op">></span> <span class="op">=</span> <span class="ident">HashMap</span>::<span class="ident">new</span>();
<span class="ident">map</span>.<span class="ident">entry</span>(<span class="string">"poneyland"</span>).<span class="ident">or_insert</span>(<span class="number">12</span>);
<span class="kw">if</span> <span class="kw">let</span> <span class="ident">Entry</span>::<span class="ident">Occupied</span>(<span class="ident">o</span>) <span class="op">=</span> <span class="ident">map</span>.<span class="ident">entry</span>(<span class="string">"poneyland"</span>) {
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">o</span>.<span class="ident">remove</span>(), <span class="number">12</span>);
}
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">map</span>.<span class="ident">contains_key</span>(<span class="string">"poneyland"</span>), <span class="bool-val">false</span>);<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Acollections%3A%3AHashMap%3B%0Ause%20std%3A%3Acollections%3A%3Ahash_map%3A%3AEntry%3B%0A%0Alet%20mut%20map%3A%20HashMap%3C%26str%2C%20u32%3E%20%3D%20HashMap%3A%3Anew()%3B%0Amap.entry(%22poneyland%22).or_insert(12)%3B%0A%0Aif%20let%20Entry%3A%3AOccupied(o)%20%3D%20map.entry(%22poneyland%22)%20%7B%0A%20%20%20%20assert_eq!(o.remove()%2C%2012)%3B%0A%7D%0A%0Aassert_eq!(map.contains_key(%22poneyland%22)%2C%20false)%3B%0A%7D">Run</a></pre>
</div><h4 id='method.replace_entry' class="method"><span id='replace_entry.v' class='invisible'><code>pub fn <a href='#method.replace_entry' class='fnname'>replace_entry</a>(self, value: V) -> <a class="primitive" href="../../primitive.tuple.html">(</a>K, V<a class="primitive" href="../../primitive.tuple.html">)</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/std/collections/hash/map.rs.html#2309-2316' title='goto source code'>[src]</a></span></h4>
<div class='stability'><div class='stab unstable'><span class=microscope>🔬</span> This is a nightly-only experimental API. (<code>map_entry_replace </code><a href="https://github.com/rust-lang/rust/issues/44286">#44286</a>)</div></div><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>
<h1 id="examples-7" class="section-header"><a href="#examples-7">Examples</a></h1>
<pre class="rust rust-example-rendered">
<span class="attribute">#![<span class="ident">feature</span>(<span class="ident">map_entry_replace</span>)]</span>
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">hash_map</span>::{<span class="ident">Entry</span>, <span class="ident">HashMap</span>};
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">rc</span>::<span class="ident">Rc</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">map</span>: <span class="ident">HashMap</span><span class="op"><</span><span class="ident">Rc</span><span class="op"><</span><span class="ident">String</span><span class="op">></span>, <span class="ident">u32</span><span class="op">></span> <span class="op">=</span> <span class="ident">HashMap</span>::<span class="ident">new</span>();
<span class="ident">map</span>.<span class="ident">insert</span>(<span class="ident">Rc</span>::<span class="ident">new</span>(<span class="string">"Stringthing"</span>.<span class="ident">to_string</span>()), <span class="number">15</span>);
<span class="kw">let</span> <span class="ident">my_key</span> <span class="op">=</span> <span class="ident">Rc</span>::<span class="ident">new</span>(<span class="string">"Stringthing"</span>.<span class="ident">to_string</span>());
<span class="kw">if</span> <span class="kw">let</span> <span class="ident">Entry</span>::<span class="ident">Occupied</span>(<span class="ident">entry</span>) <span class="op">=</span> <span class="ident">map</span>.<span class="ident">entry</span>(<span class="ident">my_key</span>) {
<span class="comment">// Also replace the key with a handle to our other key.</span>
<span class="kw">let</span> (<span class="ident">old_key</span>, <span class="ident">old_value</span>): (<span class="ident">Rc</span><span class="op"><</span><span class="ident">String</span><span class="op">></span>, <span class="ident">u32</span>) <span class="op">=</span> <span class="ident">entry</span>.<span class="ident">replace_entry</span>(<span class="number">16</span>);
}
<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0A%23!%5Bfeature(map_entry_replace)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Acollections%3A%3Ahash_map%3A%3A%7BEntry%2C%20HashMap%7D%3B%0Ause%20std%3A%3Arc%3A%3ARc%3B%0A%0Alet%20mut%20map%3A%20HashMap%3CRc%3CString%3E%2C%20u32%3E%20%3D%20HashMap%3A%3Anew()%3B%0Amap.insert(Rc%3A%3Anew(%22Stringthing%22.to_string())%2C%2015)%3B%0A%0Alet%20my_key%20%3D%20Rc%3A%3Anew(%22Stringthing%22.to_string())%3B%0A%0Aif%20let%20Entry%3A%3AOccupied(entry)%20%3D%20map.entry(my_key)%20%7B%0A%20%20%20%20%2F%2F%20Also%20replace%20the%20key%20with%20a%20handle%20to%20our%20other%20key.%0A%20%20%20%20let%20(old_key%2C%20old_value)%3A%20(Rc%3CString%3E%2C%20u32)%20%3D%20entry.replace_entry(16)%3B%0A%7D%0A%7D&version=nightly">Run</a></pre>
</div><h4 id='method.replace_key' class="method"><span id='replace_key.v' class='invisible'><code>pub fn <a href='#method.replace_key' class='fnname'>replace_key</a>(self) -> K</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/std/collections/hash/map.rs.html#2344-2347' title='goto source code'>[src]</a></span></h4>
<div class='stability'><div class='stab unstable'><span class=microscope>🔬</span> This is a nightly-only experimental API. (<code>map_entry_replace </code><a href="https://github.com/rust-lang/rust/issues/44286">#44286</a>)</div></div><div class='docblock'><p>Replaces the key in the hash map with the key used to create this entry.</p>
<h1 id="examples-8" class="section-header"><a href="#examples-8">Examples</a></h1>
<pre class="rust rust-example-rendered">
<span class="attribute">#![<span class="ident">feature</span>(<span class="ident">map_entry_replace</span>)]</span>
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">collections</span>::<span class="ident">hash_map</span>::{<span class="ident">Entry</span>, <span class="ident">HashMap</span>};
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">rc</span>::<span class="ident">Rc</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">map</span>: <span class="ident">HashMap</span><span class="op"><</span><span class="ident">Rc</span><span class="op"><</span><span class="ident">String</span><span class="op">></span>, <span class="ident">u32</span><span class="op">></span> <span class="op">=</span> <span class="ident">HashMap</span>::<span class="ident">new</span>();
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">known_strings</span>: <span class="ident">Vec</span><span class="op"><</span><span class="ident">Rc</span><span class="op"><</span><span class="ident">String</span><span class="op">>></span> <span class="op">=</span> <span class="ident">Vec</span>::<span class="ident">new</span>();
<span class="comment">// Initialise known strings, run program, etc.</span>
<span class="ident">reclaim_memory</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">map</span>, <span class="kw-2">&</span><span class="ident">known_strings</span>);
<span class="kw">fn</span> <span class="ident">reclaim_memory</span>(<span class="ident">map</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">HashMap</span><span class="op"><</span><span class="ident">Rc</span><span class="op"><</span><span class="ident">String</span><span class="op">></span>, <span class="ident">u32</span><span class="op">></span>, <span class="ident">known_strings</span>: <span class="kw-2">&</span>[<span class="ident">Rc</span><span class="op"><</span><span class="ident">String</span><span class="op">></span>] ) {
<span class="kw">for</span> <span class="ident">s</span> <span class="kw">in</span> <span class="ident">known_strings</span> {
<span class="kw">if</span> <span class="kw">let</span> <span class="ident">Entry</span>::<span class="ident">Occupied</span>(<span class="ident">entry</span>) <span class="op">=</span> <span class="ident">map</span>.<span class="ident">entry</span>(<span class="ident">s</span>.<span class="ident">clone</span>()) {
<span class="comment">// Replaces the entry's key with our version of it in `known_strings`.</span>
<span class="ident">entry</span>.<span class="ident">replace_key</span>();
}
}
}<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0A%23!%5Bfeature(map_entry_replace)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Acollections%3A%3Ahash_map%3A%3A%7BEntry%2C%20HashMap%7D%3B%0Ause%20std%3A%3Arc%3A%3ARc%3B%0A%0Alet%20mut%20map%3A%20HashMap%3CRc%3CString%3E%2C%20u32%3E%20%3D%20HashMap%3A%3Anew()%3B%0Alet%20mut%20known_strings%3A%20Vec%3CRc%3CString%3E%3E%20%3D%20Vec%3A%3Anew()%3B%0A%0A%2F%2F%20Initialise%20known%20strings%2C%20run%20program%2C%20etc.%0A%0Areclaim_memory(%26mut%20map%2C%20%26known_strings)%3B%0A%0Afn%20reclaim_memory(map%3A%20%26mut%20HashMap%3CRc%3CString%3E%2C%20u32%3E%2C%20known_strings%3A%20%26%5BRc%3CString%3E%5D%20)%20%7B%0A%20%20%20%20for%20s%20in%20known_strings%20%7B%0A%20%20%20%20%20%20%20%20if%20let%20Entry%3A%3AOccupied(entry)%20%3D%20map.entry(s.clone())%20%7B%0A%20%20%20%20%20%20%20%20%20%20%20%20%2F%2F%20Replaces%20the%20entry's%20key%20with%20our%20version%20of%20it%20in%20%60known_strings%60.%0A%20%20%20%20%20%20%20%20%20%20%20%20entry.replace_key()%3B%0A%20%20%20%20%20%20%20%20%7D%0A%20%20%20%20%7D%0A%7D%0A%7D&version=nightly">Run</a></pre>
</div></div>
<h2 id='implementations' class='small-section-header'>
Trait Implementations<a href='#implementations' class='anchor'></a>
</h2>
<h3 id='impl-Debug' class='impl'><span class='in-band'><code>impl<'a, K: 'a + <a class="trait" href="../../../std/fmt/trait.Debug.html" title="trait std::fmt::Debug">Debug</a>, V: 'a + <a class="trait" href="../../../std/fmt/trait.Debug.html" title="trait std::fmt::Debug">Debug</a>> <a class="trait" href="../../../std/fmt/trait.Debug.html" title="trait std::fmt::Debug">Debug</a> for <a class="struct" href="../../../std/collections/hash_map/struct.OccupiedEntry.html" title="struct std::collections::hash_map::OccupiedEntry">OccupiedEntry</a><'a, K, V></code><a href='#impl-Debug' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.12.0'>1.12.0</div><a class='srclink' href='../../../src/std/collections/hash/map.rs.html#1622-1629' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.fmt' class="method"><span id='fmt.v' class='invisible'><code>fn <a href='../../../std/fmt/trait.Debug.html#tymethod.fmt' class='fnname'>fmt</a>(&self, f: &mut <a class="struct" href="../../../std/fmt/struct.Formatter.html" title="struct std::fmt::Formatter">Formatter</a>) -> <a class="type" href="../../../std/fmt/type.Result.html" title="type std::fmt::Result">Result</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../../src/std/collections/hash/map.rs.html#1623-1628' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Formats the value using the given formatter. <a href="../../../std/fmt/trait.Debug.html#tymethod.fmt">Read more</a></p>
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