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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 thread-safe cell which can be written to only once."><title>OnceCell in once_cell::sync - Rust</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/SourceSerif4-Regular-46f98efaafac5295.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/FiraSans-Regular-018c141bf0843ffd.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/FiraSans-Medium-8f9a781e4970d388.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/SourceCodePro-Regular-562dcc5011b6de7d.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/SourceCodePro-Semibold-d899c5a5c4aeb14a.ttf.woff2"><link rel="stylesheet" href="../../static.files/normalize-76eba96aa4d2e634.css"><link rel="stylesheet" href="../../static.files/rustdoc-5bc39a1768837dd0.css"><meta name="rustdoc-vars" data-root-path="../../" data-static-root-path="../../static.files/" data-current-crate="once_cell" data-themes="" data-resource-suffix="" data-rustdoc-version="1.77.1 (7cf61ebde 2024-03-27)" data-channel="1.77.1" data-search-js="search-dd67cee4cfa65049.js" data-settings-js="settings-4313503d2e1961c2.js" ><script src="../../static.files/storage-4c98445ec4002617.js"></script><script defer src="sidebar-items.js"></script><script defer src="../../static.files/main-48f368f3872407c8.js"></script><noscript><link rel="stylesheet" href="../../static.files/noscript-04d5337699b92874.css"></noscript><link rel="alternate icon" type="image/png" href="../../static.files/favicon-16x16-8b506e7a72182f1c.png"><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="../../once_cell/index.html">once_cell</a><span class="version">1.19.0</span></h2></div><h2 class="location"><a href="#">OnceCell</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.get_or_init">get_or_init</a></li><li><a href="#method.get_or_try_init">get_or_try_init</a></li><li><a href="#method.get_unchecked">get_unchecked</a></li><li><a href="#method.into_inner">into_inner</a></li><li><a href="#method.new">new</a></li><li><a href="#method.set">set</a></li><li><a href="#method.take">take</a></li><li><a href="#method.try_insert">try_insert</a></li><li><a href="#method.wait">wait</a></li><li><a href="#method.with_value">with_value</a></li></ul><h3><a href="#trait-implementations">Trait Implementations</a></h3><ul class="block trait-implementation"><li><a href="#impl-Clone-for-OnceCell%3CT%3E">Clone</a></li><li><a href="#impl-Debug-for-OnceCell%3CT%3E">Debug</a></li><li><a href="#impl-Default-for-OnceCell%3CT%3E">Default</a></li><li><a href="#impl-Eq-for-OnceCell%3CT%3E">Eq</a></li><li><a href="#impl-From%3CT%3E-for-OnceCell%3CT%3E">From&lt;T&gt;</a></li><li><a href="#impl-PartialEq-for-OnceCell%3CT%3E">PartialEq</a></li></ul><h3><a href="#synthetic-implementations">Auto Trait Implementations</a></h3><ul class="block synthetic-implementation"><li><a href="#impl-RefUnwindSafe-for-OnceCell%3CT%3E">RefUnwindSafe</a></li><li><a href="#impl-Send-for-OnceCell%3CT%3E">Send</a></li><li><a href="#impl-Sync-for-OnceCell%3CT%3E">Sync</a></li><li><a href="#impl-Unpin-for-OnceCell%3CT%3E">Unpin</a></li><li><a href="#impl-UnwindSafe-for-OnceCell%3CT%3E">UnwindSafe</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%3C!%3E-for-T">From&lt;!&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-ToOwned-for-T">ToOwned</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 once_cell::sync</a></h2></div></nav><div class="sidebar-resizer"></div>
<main><div class="width-limiter"><nav class="sub"><form class="search-form"><span></span><div id="sidebar-button" tabindex="-1"><a href="../../once_cell/all.html" title="show sidebar"></a></div><input class="search-input" name="search" aria-label="Run search in the documentation" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" tabindex="-1"><a href="../../help.html" title="help">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../static.files/wheel-7b819b6101059cd0.svg"></a></div></form></nav><section id="main-content" class="content"><div class="main-heading"><h1>Struct <a href="../index.html">once_cell</a>::<wbr><a href="index.html">sync</a>::<wbr><a class="struct" href="#">OnceCell</a><button id="copy-path" title="Copy item path to clipboard"><img src="../../static.files/clipboard-7571035ce49a181d.svg" width="19" height="18" alt="Copy item path"></button></h1><span class="out-of-band"><a class="src" href="../../src/once_cell/lib.rs.html#901">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 OnceCell&lt;T&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 thread-safe cell which can be written to only once.</p>
<p><code>OnceCell</code> provides <code>&amp;</code> references to the contents without RAII guards.</p>
<p>Reading a non-<code>None</code> value out of <code>OnceCell</code> establishes a
happens-before relationship with a corresponding write. For example, if
thread A initializes the cell with <code>get_or_init(f)</code>, and thread B
subsequently reads the result of this call, B also observes all the side
effects of <code>f</code>.</p>
<h2 id="example"><a class="doc-anchor" href="#example">§</a>Example</h2>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>once_cell::sync::OnceCell;
<span class="kw">static </span>CELL: OnceCell&lt;String&gt; = OnceCell::new();
<span class="macro">assert!</span>(CELL.get().is_none());
std::thread::spawn(|| {
<span class="kw">let </span>value: <span class="kw-2">&amp;</span>String = CELL.get_or_init(|| {
<span class="string">"Hello, World!"</span>.to_string()
});
<span class="macro">assert_eq!</span>(value, <span class="string">"Hello, World!"</span>);
}).join().unwrap();
<span class="kw">let </span>value: <span class="prelude-ty">Option</span>&lt;<span class="kw-2">&amp;</span>String&gt; = CELL.get();
<span class="macro">assert!</span>(value.is_some());
<span class="macro">assert_eq!</span>(value.unwrap().as_str(), <span class="string">"Hello, World!"</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-OnceCell%3CT%3E" class="impl"><a class="src rightside" href="../../src/once_cell/lib.rs.html#948-1220">source</a><a href="#impl-OnceCell%3CT%3E" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="struct" href="struct.OnceCell.html" title="struct once_cell::sync::OnceCell">OnceCell</a>&lt;T&gt;</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.new" class="method"><a class="src rightside" href="../../src/once_cell/lib.rs.html#950-952">source</a><h4 class="code-header">pub const fn <a href="#method.new" class="fn">new</a>() -&gt; <a class="struct" href="struct.OnceCell.html" title="struct once_cell::sync::OnceCell">OnceCell</a>&lt;T&gt;</h4></section></summary><div class="docblock"><p>Creates a new empty cell.</p>
</div></details><details class="toggle method-toggle" open><summary><section id="method.with_value" class="method"><a class="src rightside" href="../../src/once_cell/lib.rs.html#955-957">source</a><h4 class="code-header">pub const fn <a href="#method.with_value" class="fn">with_value</a>(value: T) -&gt; <a class="struct" href="struct.OnceCell.html" title="struct once_cell::sync::OnceCell">OnceCell</a>&lt;T&gt;</h4></section></summary><div class="docblock"><p>Creates a new initialized cell.</p>
</div></details><details class="toggle method-toggle" open><summary><section id="method.get" class="method"><a class="src rightside" href="../../src/once_cell/lib.rs.html#963-970">source</a><h4 class="code-header">pub fn <a href="#method.get" class="fn">get</a>(&amp;self) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.77.1/core/option/enum.Option.html" title="enum core::option::Option">Option</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/1.77.1/std/primitive.reference.html">&amp;T</a>&gt;</h4></section></summary><div class="docblock"><p>Gets the reference to the underlying value.</p>
<p>Returns <code>None</code> if the cell is empty, or being initialized. This
method never blocks.</p>
</div></details><details class="toggle method-toggle" open><summary><section id="method.wait" class="method"><a class="src rightside" href="../../src/once_cell/lib.rs.html#993-1001">source</a><h4 class="code-header">pub fn <a href="#method.wait" class="fn">wait</a>(&amp;self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.77.1/std/primitive.reference.html">&amp;T</a></h4></section></summary><div class="docblock"><p>Gets the reference to the underlying value, blocking the current
thread until it is set.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>once_cell::sync::OnceCell;
<span class="kw">let </span><span class="kw-2">mut </span>cell = std::sync::Arc::new(OnceCell::new());
<span class="kw">let </span>t = std::thread::spawn({
<span class="kw">let </span>cell = std::sync::Arc::clone(<span class="kw-2">&amp;</span>cell);
<span class="kw">move </span>|| cell.set(<span class="number">92</span>).unwrap()
});
<span class="comment">// Returns immediately, but might return None.
</span><span class="kw">let </span>_value_or_none = cell.get();
<span class="comment">// Will return 92, but might block until the other thread does `.set`.
</span><span class="kw">let </span>value: <span class="kw-2">&amp;</span>u32 = cell.wait();
<span class="macro">assert_eq!</span>(<span class="kw-2">*</span>value, <span class="number">92</span>);
t.join().unwrap();</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/once_cell/lib.rs.html#1019-1021">source</a><h4 class="code-header">pub fn <a href="#method.get_mut" class="fn">get_mut</a>(&amp;mut self) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.77.1/core/option/enum.Option.html" title="enum core::option::Option">Option</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/1.77.1/std/primitive.reference.html">&amp;mut T</a>&gt;</h4></section></summary><div class="docblock"><p>Gets the mutable reference to the underlying value.</p>
<p>Returns <code>None</code> if the cell is empty.</p>
<p>This method is allowed to violate the invariant of writing to a <code>OnceCell</code>
at most once because it requires <code>&amp;mut</code> access to <code>self</code>. As with all
interior mutability, <code>&amp;mut</code> access permits arbitrary modification:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>once_cell::sync::OnceCell;
<span class="kw">let </span><span class="kw-2">mut </span>cell: OnceCell&lt;u32&gt; = OnceCell::new();
cell.set(<span class="number">92</span>).unwrap();
cell = OnceCell::new();</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.get_unchecked" class="method"><a class="src rightside" href="../../src/once_cell/lib.rs.html#1031-1033">source</a><h4 class="code-header">pub unsafe fn <a href="#method.get_unchecked" class="fn">get_unchecked</a>(&amp;self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.77.1/std/primitive.reference.html">&amp;T</a></h4></section></summary><div class="docblock"><p>Get the reference to the underlying value, without checking if the
cell is initialized.</p>
<h5 id="safety"><a class="doc-anchor" href="#safety">§</a>Safety</h5>
<p>Caller must ensure that the cell is in initialized state, and that
the contents are acquired by (synchronized to) this thread.</p>
</div></details><details class="toggle method-toggle" open><summary><section id="method.set" class="method"><a class="src rightside" href="../../src/once_cell/lib.rs.html#1058-1063">source</a><h4 class="code-header">pub fn <a href="#method.set" class="fn">set</a>(&amp;self, value: T) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.77.1/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/1.77.1/std/primitive.unit.html">()</a>, T&gt;</h4></section></summary><div class="docblock"><p>Sets the contents of this cell to <code>value</code>.</p>
<p>Returns <code>Ok(())</code> if the cell was empty and <code>Err(value)</code> if it was
full.</p>
<h5 id="example-1"><a class="doc-anchor" href="#example-1">§</a>Example</h5>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>once_cell::sync::OnceCell;
<span class="kw">static </span>CELL: OnceCell&lt;i32&gt; = OnceCell::new();
<span class="kw">fn </span>main() {
<span class="macro">assert!</span>(CELL.get().is_none());
std::thread::spawn(|| {
<span class="macro">assert_eq!</span>(CELL.set(<span class="number">92</span>), <span class="prelude-val">Ok</span>(()));
}).join().unwrap();
<span class="macro">assert_eq!</span>(CELL.set(<span class="number">62</span>), <span class="prelude-val">Err</span>(<span class="number">62</span>));
<span class="macro">assert_eq!</span>(CELL.get(), <span class="prelude-val">Some</span>(<span class="kw-2">&amp;</span><span class="number">92</span>));
}</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.try_insert" class="method"><a class="src rightside" href="../../src/once_cell/lib.rs.html#1080-1087">source</a><h4 class="code-header">pub fn <a href="#method.try_insert" class="fn">try_insert</a>(&amp;self, value: T) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.77.1/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/1.77.1/std/primitive.reference.html">&amp;T</a>, (<a class="primitive" href="https://doc.rust-lang.org/1.77.1/std/primitive.reference.html">&amp;T</a>, T)&gt;</h4></section></summary><div class="docblock"><p>Like <a href="struct.OnceCell.html#method.set" title="method once_cell::sync::OnceCell::set"><code>set</code></a>, but also returns a reference to the final cell value.</p>
<h5 id="example-2"><a class="doc-anchor" href="#example-2">§</a>Example</h5>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>once_cell::unsync::OnceCell;
<span class="kw">let </span>cell = OnceCell::new();
<span class="macro">assert!</span>(cell.get().is_none());
<span class="macro">assert_eq!</span>(cell.try_insert(<span class="number">92</span>), <span class="prelude-val">Ok</span>(<span class="kw-2">&amp;</span><span class="number">92</span>));
<span class="macro">assert_eq!</span>(cell.try_insert(<span class="number">62</span>), <span class="prelude-val">Err</span>((<span class="kw-2">&amp;</span><span class="number">92</span>, <span class="number">62</span>)));
<span class="macro">assert!</span>(cell.get().is_some());</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.get_or_init" class="method"><a class="src rightside" href="../../src/once_cell/lib.rs.html#1115-1124">source</a><h4 class="code-header">pub fn <a href="#method.get_or_init" class="fn">get_or_init</a>&lt;F&gt;(&amp;self, f: F) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.77.1/std/primitive.reference.html">&amp;T</a><div class="where">where
F: <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/ops/function/trait.FnOnce.html" title="trait core::ops::function::FnOnce">FnOnce</a>() -&gt; T,</div></h4></section></summary><div class="docblock"><p>Gets the contents of the cell, initializing it with <code>f</code> if the cell
was empty.</p>
<p>Many threads may call <code>get_or_init</code> concurrently with different
initializing functions, but it is guaranteed that only one function
will be executed.</p>
<h5 id="panics"><a class="doc-anchor" href="#panics">§</a>Panics</h5>
<p>If <code>f</code> panics, the panic is propagated to the caller, and the cell
remains uninitialized.</p>
<p>It is an error to reentrantly initialize the cell from <code>f</code>. The
exact outcome is unspecified. Current implementation deadlocks, but
this may be changed to a panic in the future.</p>
<h5 id="example-3"><a class="doc-anchor" href="#example-3">§</a>Example</h5>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>once_cell::sync::OnceCell;
<span class="kw">let </span>cell = OnceCell::new();
<span class="kw">let </span>value = cell.get_or_init(|| <span class="number">92</span>);
<span class="macro">assert_eq!</span>(value, <span class="kw-2">&amp;</span><span class="number">92</span>);
<span class="kw">let </span>value = cell.get_or_init(|| <span class="macro">unreachable!</span>());
<span class="macro">assert_eq!</span>(value, <span class="kw-2">&amp;</span><span class="number">92</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.get_or_try_init" class="method"><a class="src rightside" href="../../src/once_cell/lib.rs.html#1152-1166">source</a><h4 class="code-header">pub fn <a href="#method.get_or_try_init" class="fn">get_or_try_init</a>&lt;F, E&gt;(&amp;self, f: F) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.77.1/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/1.77.1/std/primitive.reference.html">&amp;T</a>, E&gt;<div class="where">where
F: <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/ops/function/trait.FnOnce.html" title="trait core::ops::function::FnOnce">FnOnce</a>() -&gt; <a class="enum" href="https://doc.rust-lang.org/1.77.1/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;T, E&gt;,</div></h4></section></summary><div class="docblock"><p>Gets the contents of the cell, initializing it with <code>f</code> if
the cell was empty. If the cell was empty and <code>f</code> failed, an
error is returned.</p>
<h5 id="panics-1"><a class="doc-anchor" href="#panics-1">§</a>Panics</h5>
<p>If <code>f</code> panics, the panic is propagated to the caller, and
the cell remains uninitialized.</p>
<p>It is an error to reentrantly initialize the cell from <code>f</code>.
The exact outcome is unspecified. Current implementation
deadlocks, but this may be changed to a panic in the future.</p>
<h5 id="example-4"><a class="doc-anchor" href="#example-4">§</a>Example</h5>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>once_cell::sync::OnceCell;
<span class="kw">let </span>cell = OnceCell::new();
<span class="macro">assert_eq!</span>(cell.get_or_try_init(|| <span class="prelude-val">Err</span>(())), <span class="prelude-val">Err</span>(()));
<span class="macro">assert!</span>(cell.get().is_none());
<span class="kw">let </span>value = cell.get_or_try_init(|| -&gt; <span class="prelude-ty">Result</span>&lt;i32, ()&gt; {
<span class="prelude-val">Ok</span>(<span class="number">92</span>)
});
<span class="macro">assert_eq!</span>(value, <span class="prelude-val">Ok</span>(<span class="kw-2">&amp;</span><span class="number">92</span>));
<span class="macro">assert_eq!</span>(cell.get(), <span class="prelude-val">Some</span>(<span class="kw-2">&amp;</span><span class="number">92</span>))</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.take" class="method"><a class="src rightside" href="../../src/once_cell/lib.rs.html#1197-1199">source</a><h4 class="code-header">pub fn <a href="#method.take" class="fn">take</a>(&amp;mut self) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.77.1/core/option/enum.Option.html" title="enum core::option::Option">Option</a>&lt;T&gt;</h4></section></summary><div class="docblock"><p>Takes the value out of this <code>OnceCell</code>, moving it back to an uninitialized state.</p>
<p>Has no effect and returns <code>None</code> if the <code>OnceCell</code> hasn’t been initialized.</p>
<h5 id="examples"><a class="doc-anchor" href="#examples">§</a>Examples</h5>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>once_cell::sync::OnceCell;
<span class="kw">let </span><span class="kw-2">mut </span>cell: OnceCell&lt;String&gt; = OnceCell::new();
<span class="macro">assert_eq!</span>(cell.take(), <span class="prelude-val">None</span>);
<span class="kw">let </span><span class="kw-2">mut </span>cell = OnceCell::new();
cell.set(<span class="string">"hello"</span>.to_string()).unwrap();
<span class="macro">assert_eq!</span>(cell.take(), <span class="prelude-val">Some</span>(<span class="string">"hello"</span>.to_string()));
<span class="macro">assert_eq!</span>(cell.get(), <span class="prelude-val">None</span>);</code></pre></div>
<p>This method is allowed to violate the invariant of writing to a <code>OnceCell</code>
at most once because it requires <code>&amp;mut</code> access to <code>self</code>. As with all
interior mutability, <code>&amp;mut</code> access permits arbitrary modification:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>once_cell::sync::OnceCell;
<span class="kw">let </span><span class="kw-2">mut </span>cell: OnceCell&lt;u32&gt; = OnceCell::new();
cell.set(<span class="number">92</span>).unwrap();
cell = OnceCell::new();</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.into_inner" class="method"><a class="src rightside" href="../../src/once_cell/lib.rs.html#1217-1219">source</a><h4 class="code-header">pub fn <a href="#method.into_inner" class="fn">into_inner</a>(self) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.77.1/core/option/enum.Option.html" title="enum core::option::Option">Option</a>&lt;T&gt;</h4></section></summary><div class="docblock"><p>Consumes the <code>OnceCell</code>, returning the wrapped value. Returns
<code>None</code> if the cell was empty.</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>once_cell::sync::OnceCell;
<span class="kw">let </span>cell: OnceCell&lt;String&gt; = OnceCell::new();
<span class="macro">assert_eq!</span>(cell.into_inner(), <span class="prelude-val">None</span>);
<span class="kw">let </span>cell = OnceCell::new();
cell.set(<span class="string">"hello"</span>.to_string()).unwrap();
<span class="macro">assert_eq!</span>(cell.into_inner(), <span class="prelude-val">Some</span>(<span class="string">"hello"</span>.to_string()));</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-Clone-for-OnceCell%3CT%3E" class="impl"><a class="src rightside" href="../../src/once_cell/lib.rs.html#918-932">source</a><a href="#impl-Clone-for-OnceCell%3CT%3E" class="anchor">§</a><h3 class="code-header">impl&lt;T: <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/clone/trait.Clone.html" title="trait core::clone::Clone">Clone</a>&gt; <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/clone/trait.Clone.html" title="trait core::clone::Clone">Clone</a> for <a class="struct" href="struct.OnceCell.html" title="struct once_cell::sync::OnceCell">OnceCell</a>&lt;T&gt;</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.clone" class="method trait-impl"><a class="src rightside" href="../../src/once_cell/lib.rs.html#919-924">source</a><a href="#method.clone" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.77.1/core/clone/trait.Clone.html#tymethod.clone" class="fn">clone</a>(&amp;self) -&gt; <a class="struct" href="struct.OnceCell.html" title="struct once_cell::sync::OnceCell">OnceCell</a>&lt;T&gt;</h4></section></summary><div class='docblock'>Returns a copy of the value. <a href="https://doc.rust-lang.org/1.77.1/core/clone/trait.Clone.html#tymethod.clone">Read more</a></div></details><details class="toggle method-toggle" open><summary><section id="method.clone_from" class="method trait-impl"><a class="src rightside" href="../../src/once_cell/lib.rs.html#926-931">source</a><a href="#method.clone_from" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.77.1/core/clone/trait.Clone.html#method.clone_from" class="fn">clone_from</a>(&amp;mut self, source: <a class="primitive" href="https://doc.rust-lang.org/1.77.1/std/primitive.reference.html">&amp;Self</a>)</h4></section></summary><div class='docblock'>Performs copy-assignment from <code>source</code>. <a href="https://doc.rust-lang.org/1.77.1/core/clone/trait.Clone.html#method.clone_from">Read more</a></div></details></div></details><details class="toggle implementors-toggle" open><summary><section id="impl-Debug-for-OnceCell%3CT%3E" class="impl"><a class="src rightside" href="../../src/once_cell/lib.rs.html#909-916">source</a><a href="#impl-Debug-for-OnceCell%3CT%3E" class="anchor">§</a><h3 class="code-header">impl&lt;T: <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a>&gt; <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> for <a class="struct" href="struct.OnceCell.html" title="struct once_cell::sync::OnceCell">OnceCell</a>&lt;T&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/once_cell/lib.rs.html#910-915">source</a><a href="#method.fmt" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.77.1/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/1.77.1/core/fmt/struct.Formatter.html" title="struct core::fmt::Formatter">Formatter</a>&lt;'_&gt;) -&gt; <a class="type" href="https://doc.rust-lang.org/1.77.1/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/1.77.1/core/fmt/trait.Debug.html#tymethod.fmt">Read more</a></div></details></div></details><details class="toggle implementors-toggle" open><summary><section id="impl-Default-for-OnceCell%3CT%3E" class="impl"><a class="src rightside" href="../../src/once_cell/lib.rs.html#903-907">source</a><a href="#impl-Default-for-OnceCell%3CT%3E" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/default/trait.Default.html" title="trait core::default::Default">Default</a> for <a class="struct" href="struct.OnceCell.html" title="struct once_cell::sync::OnceCell">OnceCell</a>&lt;T&gt;</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.default" class="method trait-impl"><a class="src rightside" href="../../src/once_cell/lib.rs.html#904-906">source</a><a href="#method.default" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.77.1/core/default/trait.Default.html#tymethod.default" class="fn">default</a>() -&gt; <a class="struct" href="struct.OnceCell.html" title="struct once_cell::sync::OnceCell">OnceCell</a>&lt;T&gt;</h4></section></summary><div class='docblock'>Returns the “default value” for a type. <a href="https://doc.rust-lang.org/1.77.1/core/default/trait.Default.html#tymethod.default">Read more</a></div></details></div></details><details class="toggle implementors-toggle" open><summary><section id="impl-From%3CT%3E-for-OnceCell%3CT%3E" class="impl"><a class="src rightside" href="../../src/once_cell/lib.rs.html#934-938">source</a><a href="#impl-From%3CT%3E-for-OnceCell%3CT%3E" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;T&gt; for <a class="struct" href="struct.OnceCell.html" title="struct once_cell::sync::OnceCell">OnceCell</a>&lt;T&gt;</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="../../src/once_cell/lib.rs.html#935-937">source</a><a href="#method.from" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.77.1/core/convert/trait.From.html#tymethod.from" class="fn">from</a>(value: T) -&gt; Self</h4></section></summary><div class='docblock'>Converts to this type from the input type.</div></details></div></details><details class="toggle implementors-toggle" open><summary><section id="impl-PartialEq-for-OnceCell%3CT%3E" class="impl"><a class="src rightside" href="../../src/once_cell/lib.rs.html#940-944">source</a><a href="#impl-PartialEq-for-OnceCell%3CT%3E" class="anchor">§</a><h3 class="code-header">impl&lt;T: <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/cmp/trait.PartialEq.html" title="trait core::cmp::PartialEq">PartialEq</a>&gt; <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/cmp/trait.PartialEq.html" title="trait core::cmp::PartialEq">PartialEq</a> for <a class="struct" href="struct.OnceCell.html" title="struct once_cell::sync::OnceCell">OnceCell</a>&lt;T&gt;</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.eq" class="method trait-impl"><a class="src rightside" href="../../src/once_cell/lib.rs.html#941-943">source</a><a href="#method.eq" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.77.1/core/cmp/trait.PartialEq.html#tymethod.eq" class="fn">eq</a>(&amp;self, other: &amp;<a class="struct" href="struct.OnceCell.html" title="struct once_cell::sync::OnceCell">OnceCell</a>&lt;T&gt;) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.77.1/std/primitive.bool.html">bool</a></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>.</div></details><details class="toggle method-toggle" open><summary><section id="method.ne" class="method trait-impl"><span class="rightside"><span class="since" title="Stable since Rust version 1.0.0">1.0.0</span> · <a class="src" href="https://doc.rust-lang.org/1.77.1/src/core/cmp.rs.html#242">source</a></span><a href="#method.ne" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.77.1/core/cmp/trait.PartialEq.html#method.ne" class="fn">ne</a>(&amp;self, other: <a class="primitive" href="https://doc.rust-lang.org/1.77.1/std/primitive.reference.html">&amp;Rhs</a>) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.77.1/std/primitive.bool.html">bool</a></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.</div></details></div></details><section id="impl-Eq-for-OnceCell%3CT%3E" class="impl"><a class="src rightside" href="../../src/once_cell/lib.rs.html#946">source</a><a href="#impl-Eq-for-OnceCell%3CT%3E" class="anchor">§</a><h3 class="code-header">impl&lt;T: <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/cmp/trait.Eq.html" title="trait core::cmp::Eq">Eq</a>&gt; <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/cmp/trait.Eq.html" title="trait core::cmp::Eq">Eq</a> for <a class="struct" href="struct.OnceCell.html" title="struct once_cell::sync::OnceCell">OnceCell</a>&lt;T&gt;</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-RefUnwindSafe-for-OnceCell%3CT%3E" class="impl"><a href="#impl-RefUnwindSafe-for-OnceCell%3CT%3E" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/panic/unwind_safe/trait.RefUnwindSafe.html" title="trait core::panic::unwind_safe::RefUnwindSafe">RefUnwindSafe</a> for <a class="struct" href="struct.OnceCell.html" title="struct once_cell::sync::OnceCell">OnceCell</a>&lt;T&gt;<div class="where">where
T: <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/panic/unwind_safe/trait.UnwindSafe.html" title="trait core::panic::unwind_safe::UnwindSafe">UnwindSafe</a> + <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/panic/unwind_safe/trait.RefUnwindSafe.html" title="trait core::panic::unwind_safe::RefUnwindSafe">RefUnwindSafe</a>,</div></h3></section><section id="impl-Send-for-OnceCell%3CT%3E" class="impl"><a href="#impl-Send-for-OnceCell%3CT%3E" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> for <a class="struct" href="struct.OnceCell.html" title="struct once_cell::sync::OnceCell">OnceCell</a>&lt;T&gt;<div class="where">where
T: <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a>,</div></h3></section><section id="impl-Sync-for-OnceCell%3CT%3E" class="impl"><a href="#impl-Sync-for-OnceCell%3CT%3E" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> for <a class="struct" href="struct.OnceCell.html" title="struct once_cell::sync::OnceCell">OnceCell</a>&lt;T&gt;<div class="where">where
T: <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> + <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a>,</div></h3></section><section id="impl-Unpin-for-OnceCell%3CT%3E" class="impl"><a href="#impl-Unpin-for-OnceCell%3CT%3E" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/marker/trait.Unpin.html" title="trait core::marker::Unpin">Unpin</a> for <a class="struct" href="struct.OnceCell.html" title="struct once_cell::sync::OnceCell">OnceCell</a>&lt;T&gt;<div class="where">where
T: <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/marker/trait.Unpin.html" title="trait core::marker::Unpin">Unpin</a>,</div></h3></section><section id="impl-UnwindSafe-for-OnceCell%3CT%3E" class="impl"><a href="#impl-UnwindSafe-for-OnceCell%3CT%3E" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/panic/unwind_safe/trait.UnwindSafe.html" title="trait core::panic::unwind_safe::UnwindSafe">UnwindSafe</a> for <a class="struct" href="struct.OnceCell.html" title="struct once_cell::sync::OnceCell">OnceCell</a>&lt;T&gt;<div class="where">where
T: <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/panic/unwind_safe/trait.UnwindSafe.html" title="trait core::panic::unwind_safe::UnwindSafe">UnwindSafe</a>,</div></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/1.77.1/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/1.77.1/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/1.77.1/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/1.77.1/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/1.77.1/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/1.77.1/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/1.77.1/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/1.77.1/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/1.77.1/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/1.77.1/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/1.77.1/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/1.77.1/core/borrow/trait.Borrow.html#tymethod.borrow" class="fn">borrow</a>(&amp;self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.77.1/std/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/1.77.1/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/1.77.1/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/1.77.1/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/1.77.1/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/1.77.1/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/1.77.1/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/1.77.1/std/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/1.77.1/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%3C!%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.77.1/src/core/convert/mod.rs.html#781">source</a><a href="#impl-From%3C!%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;<a class="primitive" href="https://doc.rust-lang.org/1.77.1/std/primitive.never.html">!</a>&gt; for T</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.from-1" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.77.1/src/core/convert/mod.rs.html#782">source</a><a href="#method.from-1" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.77.1/core/convert/trait.From.html#tymethod.from" class="fn">from</a>(t: <a class="primitive" href="https://doc.rust-lang.org/1.77.1/std/primitive.never.html">!</a>) -&gt; T</h4></section></summary><div class='docblock'>Converts to this type from the input type.</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/1.77.1/src/core/convert/mod.rs.html#764">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/1.77.1/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-2" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.77.1/src/core/convert/mod.rs.html#767">source</a><a href="#method.from-2" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.77.1/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/1.77.1/src/core/convert/mod.rs.html#747-749">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/1.77.1/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/1.77.1/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/1.77.1/src/core/convert/mod.rs.html#757">source</a><a href="#method.into" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.77.1/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/1.77.1/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-ToOwned-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.77.1/src/alloc/borrow.rs.html#83-85">source</a><a href="#impl-ToOwned-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.77.1/alloc/borrow/trait.ToOwned.html" title="trait alloc::borrow::ToOwned">ToOwned</a> for T<div class="where">where
T: <a class="trait" href="https://doc.rust-lang.org/1.77.1/core/clone/trait.Clone.html" title="trait core::clone::Clone">Clone</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle" open><summary><section id="associatedtype.Owned" class="associatedtype trait-impl"><a href="#associatedtype.Owned" class="anchor">§</a><h4 class="code-header">type <a href="https://doc.rust-lang.org/1.77.1/alloc/borrow/trait.ToOwned.html#associatedtype.Owned" class="associatedtype">Owned</a> = T</h4></section></summary><div class='docblock'>The resulting type after obtaining ownership.</div></details><details class="toggle method-toggle" open><summary><section id="method.to_owned" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.77.1/src/alloc/borrow.rs.html#88">source</a><a href="#method.to_owned" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.77.1/alloc/borrow/trait.ToOwned.html#tymethod.to_owned" class="fn">to_owned</a>(&amp;self) -&gt; T</h4></section></summary><div class='docblock'>Creates owned data from borrowed data, usually by cloning. <a href="https://doc.rust-lang.org/1.77.1/alloc/borrow/trait.ToOwned.html#tymethod.to_owned">Read more</a></div></details><details class="toggle method-toggle" open><summary><section id="method.clone_into" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.77.1/src/alloc/borrow.rs.html#92">source</a><a href="#method.clone_into" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.77.1/alloc/borrow/trait.ToOwned.html#method.clone_into" class="fn">clone_into</a>(&amp;self, target: <a class="primitive" href="https://doc.rust-lang.org/1.77.1/std/primitive.reference.html">&amp;mut T</a>)</h4></section></summary><div class='docblock'>Uses borrowed data to replace owned data, usually by cloning. <a href="https://doc.rust-lang.org/1.77.1/alloc/borrow/trait.ToOwned.html#method.clone_into">Read more</a></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/1.77.1/src/core/convert/mod.rs.html#804-806">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/1.77.1/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/1.77.1/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-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/1.77.1/core/convert/trait.TryFrom.html#associatedtype.Error" class="associatedtype">Error</a> = <a class="enum" href="https://doc.rust-lang.org/1.77.1/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/1.77.1/src/core/convert/mod.rs.html#811">source</a><a href="#method.try_from" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.77.1/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/1.77.1/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/1.77.1/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/1.77.1/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/1.77.1/src/core/convert/mod.rs.html#789-791">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/1.77.1/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/1.77.1/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" class="associatedtype trait-impl"><a href="#associatedtype.Error" class="anchor">§</a><h4 class="code-header">type <a href="https://doc.rust-lang.org/1.77.1/core/convert/trait.TryInto.html#associatedtype.Error" class="associatedtype">Error</a> = &lt;U as <a class="trait" href="https://doc.rust-lang.org/1.77.1/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/1.77.1/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/1.77.1/src/core/convert/mod.rs.html#796">source</a><a href="#method.try_into" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.77.1/core/convert/trait.TryInto.html#tymethod.try_into" class="fn">try_into</a>(self) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.77.1/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/1.77.1/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/1.77.1/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>
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