137 lines
45 KiB
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137 lines
45 KiB
HTML
<!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="Cursor-based segmenter for grapheme clusters."><title>GraphemeCursor in unicode_segmentation - Rust</title><script>if(window.location.protocol!=="file:")document.head.insertAdjacentHTML("beforeend","SourceSerif4-Regular-6b053e98.ttf.woff2,FiraSans-Regular-0fe48ade.woff2,FiraSans-Medium-e1aa3f0a.woff2,SourceCodePro-Regular-8badfe75.ttf.woff2,SourceCodePro-Semibold-aa29a496.ttf.woff2".split(",").map(f=>`<link rel="preload" as="font" type="font/woff2" crossorigin href="../static.files/${f}">`).join(""))</script><link rel="stylesheet" href="../static.files/normalize-9960930a.css"><link rel="stylesheet" href="../static.files/rustdoc-42caa33d.css"><meta name="rustdoc-vars" data-root-path="../" data-static-root-path="../static.files/" data-current-crate="unicode_segmentation" data-themes="" data-resource-suffix="" data-rustdoc-version="1.84.0 (9fc6b4312 2025-01-07)" data-channel="1.84.0" data-search-js="search-92e6798f.js" data-settings-js="settings-0f613d39.js" ><script src="../static.files/storage-59e33391.js"></script><script defer src="sidebar-items.js"></script><script defer src="../static.files/main-5f194d8c.js"></script><noscript><link rel="stylesheet" href="../static.files/noscript-893ab5e7.css"></noscript><link rel="icon" href="https://unicode-rs.github.io/unicode-rs_sm.png"></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><a class="logo-container" href="../unicode_segmentation/index.html"><img src="https://unicode-rs.github.io/unicode-rs_sm.png" alt=""></a></nav><nav class="sidebar"><div class="sidebar-crate"><a class="logo-container" href="../unicode_segmentation/index.html"><img src="https://unicode-rs.github.io/unicode-rs_sm.png" alt="logo"></a><h2><a href="../unicode_segmentation/index.html">unicode_<wbr>segmentation</a><span class="version">1.12.0</span></h2></div><div class="sidebar-elems"><section id="rustdoc-toc"><h2 class="location"><a href="#">Grapheme<wbr>Cursor</a></h2><h3><a href="#implementations">Methods</a></h3><ul class="block method"><li><a href="#method.cur_cursor" title="cur_cursor">cur_cursor</a></li><li><a href="#method.is_boundary" title="is_boundary">is_boundary</a></li><li><a href="#method.new" title="new">new</a></li><li><a href="#method.next_boundary" title="next_boundary">next_boundary</a></li><li><a href="#method.prev_boundary" title="prev_boundary">prev_boundary</a></li><li><a href="#method.provide_context" title="provide_context">provide_context</a></li><li><a href="#method.set_cursor" title="set_cursor">set_cursor</a></li></ul><h3><a href="#trait-implementations">Trait Implementations</a></h3><ul class="block trait-implementation"><li><a href="#impl-Clone-for-GraphemeCursor" title="Clone">Clone</a></li><li><a href="#impl-Debug-for-GraphemeCursor" title="Debug">Debug</a></li></ul><h3><a href="#synthetic-implementations">Auto Trait Implementations</a></h3><ul class="block synthetic-implementation"><li><a href="#impl-Freeze-for-GraphemeCursor" title="Freeze">Freeze</a></li><li><a href="#impl-RefUnwindSafe-for-GraphemeCursor" title="RefUnwindSafe">RefUnwindSafe</a></li><li><a href="#impl-Send-for-GraphemeCursor" title="Send">Send</a></li><li><a href="#impl-Sync-for-GraphemeCursor" title="Sync">Sync</a></li><li><a href="#impl-Unpin-for-GraphemeCursor" title="Unpin">Unpin</a></li><li><a href="#impl-UnwindSafe-for-GraphemeCursor" title="UnwindSafe">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" title="Any">Any</a></li><li><a href="#impl-Borrow%3CT%3E-for-T" title="Borrow<T>">Borrow<T></a></li><li><a href="#impl-BorrowMut%3CT%3E-for-T" title="BorrowMut<T>">BorrowMut<T></a></li><li><a href="#impl-CloneToUninit-for-T" title="CloneToUninit">CloneToUninit</a></li><li><a href="#impl-From%3CT%3E-for-T" title="From<T>">From<T></a></li><li><a href="#impl-Into%3CU%3E-for-T" title="Into<U>">Into<U></a></li><li><a href="#impl-TryFrom%3CU%3E-for-T" title="TryFrom<U>">TryFrom<U></a></li><li><a href="#impl-TryInto%3CU%3E-for-T" title="TryInto<U>">TryInto<U></a></li></ul></section><div id="rustdoc-modnav"><h2 class="in-crate"><a href="index.html">In crate unicode_<wbr>segmentation</a></h2></div></div></nav><div class="sidebar-resizer"></div><main><div class="width-limiter"><rustdoc-search></rustdoc-search><section id="main-content" class="content"><div class="main-heading"><span class="rustdoc-breadcrumbs"><a href="index.html">unicode_segmentation</a></span><h1>Struct <span class="struct">GraphemeCursor</span><button id="copy-path" title="Copy item path to clipboard">Copy item path</button></h1><rustdoc-toolbar></rustdoc-toolbar><span class="sub-heading"><a class="src" href="../src/unicode_segmentation/grapheme.rs.html#188-217">Source</a> </span></div><pre class="rust item-decl"><code>pub struct GraphemeCursor { <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>Cursor-based segmenter for grapheme clusters.</p>
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<p>This allows working with ropes and other datastructures where the string is not contiguous or
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fully known at initialization time.</p>
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</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-GraphemeCursor" class="impl"><a class="src rightside" href="../src/unicode_segmentation/grapheme.rs.html#284-837">Source</a><a href="#impl-GraphemeCursor" class="anchor">§</a><h3 class="code-header">impl <a class="struct" href="struct.GraphemeCursor.html" title="struct unicode_segmentation::GraphemeCursor">GraphemeCursor</a></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/unicode_segmentation/grapheme.rs.html#299-318">Source</a><h4 class="code-header">pub fn <a href="#method.new" class="fn">new</a>(offset: <a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.usize.html">usize</a>, len: <a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.usize.html">usize</a>, is_extended: <a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.bool.html">bool</a>) -> <a class="struct" href="struct.GraphemeCursor.html" title="struct unicode_segmentation::GraphemeCursor">GraphemeCursor</a></h4></section></summary><div class="docblock"><p>Create a new cursor. The string and initial offset are given at creation
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time, but the contents of the string are not. The <code>is_extended</code> parameter
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controls whether extended grapheme clusters are selected.</p>
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<p>The <code>offset</code> parameter must be on a codepoint boundary.</p>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">let </span>s = <span class="string">"हिन्दी"</span>;
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<span class="kw">let </span><span class="kw-2">mut </span>legacy = GraphemeCursor::new(<span class="number">0</span>, s.len(), <span class="bool-val">false</span>);
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<span class="macro">assert_eq!</span>(legacy.next_boundary(s, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="string">"ह"</span>.len())));
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<span class="kw">let </span><span class="kw-2">mut </span>extended = GraphemeCursor::new(<span class="number">0</span>, s.len(), <span class="bool-val">true</span>);
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<span class="macro">assert_eq!</span>(extended.next_boundary(s, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="string">"हि"</span>.len())));</code></pre></div>
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</div></details><details class="toggle method-toggle" open><summary><section id="method.set_cursor" class="method"><a class="src rightside" href="../src/unicode_segmentation/grapheme.rs.html#360-374">Source</a><h4 class="code-header">pub fn <a href="#method.set_cursor" class="fn">set_cursor</a>(&mut self, offset: <a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.usize.html">usize</a>)</h4></section></summary><div class="docblock"><p>Set the cursor to a new location in the same string.</p>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">let </span>s = <span class="string">"abcd"</span>;
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<span class="kw">let </span><span class="kw-2">mut </span>cursor = GraphemeCursor::new(<span class="number">0</span>, s.len(), <span class="bool-val">false</span>);
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<span class="macro">assert_eq!</span>(cursor.cur_cursor(), <span class="number">0</span>);
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cursor.set_cursor(<span class="number">2</span>);
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<span class="macro">assert_eq!</span>(cursor.cur_cursor(), <span class="number">2</span>);</code></pre></div>
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</div></details><details class="toggle method-toggle" open><summary><section id="method.cur_cursor" class="method"><a class="src rightside" href="../src/unicode_segmentation/grapheme.rs.html#390-392">Source</a><h4 class="code-header">pub fn <a href="#method.cur_cursor" class="fn">cur_cursor</a>(&self) -> <a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.usize.html">usize</a></h4></section></summary><div class="docblock"><p>The current offset of the cursor. Equal to the last value provided to
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<code>new()</code> or <code>set_cursor()</code>, or returned from <code>next_boundary()</code> or
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<code>prev_boundary()</code>.</p>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="comment">// Two flags (🇷🇸🇮🇴), each flag is two RIS codepoints, each RIS is 4 bytes.
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</span><span class="kw">let </span>flags = <span class="string">"\u{1F1F7}\u{1F1F8}\u{1F1EE}\u{1F1F4}"</span>;
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<span class="kw">let </span><span class="kw-2">mut </span>cursor = GraphemeCursor::new(<span class="number">4</span>, flags.len(), <span class="bool-val">false</span>);
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<span class="macro">assert_eq!</span>(cursor.cur_cursor(), <span class="number">4</span>);
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<span class="macro">assert_eq!</span>(cursor.next_boundary(flags, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">8</span>)));
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<span class="macro">assert_eq!</span>(cursor.cur_cursor(), <span class="number">8</span>);</code></pre></div>
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</div></details><details class="toggle method-toggle" open><summary><section id="method.provide_context" class="method"><a class="src rightside" href="../src/unicode_segmentation/grapheme.rs.html#413-435">Source</a><h4 class="code-header">pub fn <a href="#method.provide_context" class="fn">provide_context</a>(&mut self, chunk: &<a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.str.html">str</a>, chunk_start: <a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.usize.html">usize</a>)</h4></section></summary><div class="docblock"><p>Provide additional pre-context when it is needed to decide a boundary.
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The end of the chunk must coincide with the value given in the
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<code>GraphemeIncomplete::PreContext</code> request.</p>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">let </span>flags = <span class="string">"\u{1F1F7}\u{1F1F8}\u{1F1EE}\u{1F1F4}"</span>;
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<span class="kw">let </span><span class="kw-2">mut </span>cursor = GraphemeCursor::new(<span class="number">8</span>, flags.len(), <span class="bool-val">false</span>);
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<span class="comment">// Not enough pre-context to decide if there's a boundary between the two flags.
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</span><span class="macro">assert_eq!</span>(cursor.is_boundary(<span class="kw-2">&</span>flags[<span class="number">8</span>..], <span class="number">8</span>), <span class="prelude-val">Err</span>(GraphemeIncomplete::PreContext(<span class="number">8</span>)));
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<span class="comment">// Provide one more Regional Indicator Symbol of pre-context
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</span>cursor.provide_context(<span class="kw-2">&</span>flags[<span class="number">4</span>..<span class="number">8</span>], <span class="number">4</span>);
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<span class="comment">// Still not enough context to decide.
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</span><span class="macro">assert_eq!</span>(cursor.is_boundary(<span class="kw-2">&</span>flags[<span class="number">8</span>..], <span class="number">8</span>), <span class="prelude-val">Err</span>(GraphemeIncomplete::PreContext(<span class="number">4</span>)));
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<span class="comment">// Provide additional requested context.
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</span>cursor.provide_context(<span class="kw-2">&</span>flags[<span class="number">0</span>..<span class="number">4</span>], <span class="number">0</span>);
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<span class="comment">// That's enough to decide (it always is when context goes to the start of the string)
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</span><span class="macro">assert_eq!</span>(cursor.is_boundary(<span class="kw-2">&</span>flags[<span class="number">8</span>..], <span class="number">8</span>), <span class="prelude-val">Ok</span>(<span class="bool-val">true</span>));</code></pre></div>
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</div></details><details class="toggle method-toggle" open><summary><section id="method.is_boundary" class="method"><a class="src rightside" href="../src/unicode_segmentation/grapheme.rs.html#589-654">Source</a><h4 class="code-header">pub fn <a href="#method.is_boundary" class="fn">is_boundary</a>(
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&mut self,
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chunk: &<a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.str.html">str</a>,
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chunk_start: <a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.usize.html">usize</a>,
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) -> <a class="enum" href="https://doc.rust-lang.org/1.84.0/core/result/enum.Result.html" title="enum core::result::Result">Result</a><<a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.bool.html">bool</a>, <a class="enum" href="enum.GraphemeIncomplete.html" title="enum unicode_segmentation::GraphemeIncomplete">GraphemeIncomplete</a>></h4></section></summary><div class="docblock"><p>Determine whether the current cursor location is a grapheme cluster boundary.
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Only a part of the string need be supplied. If <code>chunk_start</code> is nonzero or
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the length of <code>chunk</code> is not equal to <code>len</code> on creation, then this method
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may return <code>GraphemeIncomplete::PreContext</code>. The caller should then
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call <code>provide_context</code> with the requested chunk, then retry calling this
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method.</p>
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<p>For partial chunks, if the cursor is not at the beginning or end of the
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string, the chunk should contain at least the codepoint following the cursor.
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If the string is nonempty, the chunk must be nonempty.</p>
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<p>All calls should have consistent chunk contents (ie, if a chunk provides
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content for a given slice, all further chunks covering that slice must have
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the same content for it).</p>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">let </span>flags = <span class="string">"\u{1F1F7}\u{1F1F8}\u{1F1EE}\u{1F1F4}"</span>;
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<span class="kw">let </span><span class="kw-2">mut </span>cursor = GraphemeCursor::new(<span class="number">8</span>, flags.len(), <span class="bool-val">false</span>);
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<span class="macro">assert_eq!</span>(cursor.is_boundary(flags, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="bool-val">true</span>));
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cursor.set_cursor(<span class="number">12</span>);
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<span class="macro">assert_eq!</span>(cursor.is_boundary(flags, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="bool-val">false</span>));</code></pre></div>
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</div></details><details class="toggle method-toggle" open><summary><section id="method.next_boundary" class="method"><a class="src rightside" href="../src/unicode_segmentation/grapheme.rs.html#689-741">Source</a><h4 class="code-header">pub fn <a href="#method.next_boundary" class="fn">next_boundary</a>(
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&mut self,
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chunk: &<a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.str.html">str</a>,
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chunk_start: <a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.usize.html">usize</a>,
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) -> <a class="enum" href="https://doc.rust-lang.org/1.84.0/core/result/enum.Result.html" title="enum core::result::Result">Result</a><<a class="enum" href="https://doc.rust-lang.org/1.84.0/core/option/enum.Option.html" title="enum core::option::Option">Option</a><<a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.usize.html">usize</a>>, <a class="enum" href="enum.GraphemeIncomplete.html" title="enum unicode_segmentation::GraphemeIncomplete">GraphemeIncomplete</a>></h4></section></summary><div class="docblock"><p>Find the next boundary after the current cursor position. Only a part of
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the string need be supplied. If the chunk is incomplete, then this
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method might return <code>GraphemeIncomplete::PreContext</code> or
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<code>GraphemeIncomplete::NextChunk</code>. In the former case, the caller should
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call <code>provide_context</code> with the requested chunk, then retry. In the
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latter case, the caller should provide the chunk following the one
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given, then retry.</p>
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<p>See <code>is_boundary</code> for expectations on the provided chunk.</p>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">let </span>flags = <span class="string">"\u{1F1F7}\u{1F1F8}\u{1F1EE}\u{1F1F4}"</span>;
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<span class="kw">let </span><span class="kw-2">mut </span>cursor = GraphemeCursor::new(<span class="number">4</span>, flags.len(), <span class="bool-val">false</span>);
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<span class="macro">assert_eq!</span>(cursor.next_boundary(flags, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">8</span>)));
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<span class="macro">assert_eq!</span>(cursor.next_boundary(flags, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">16</span>)));
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<span class="macro">assert_eq!</span>(cursor.next_boundary(flags, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">None</span>));</code></pre></div>
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<p>And an example that uses partial strings:</p>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">let </span>s = <span class="string">"abcd"</span>;
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<span class="kw">let </span><span class="kw-2">mut </span>cursor = GraphemeCursor::new(<span class="number">0</span>, s.len(), <span class="bool-val">false</span>);
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<span class="macro">assert_eq!</span>(cursor.next_boundary(<span class="kw-2">&</span>s[..<span class="number">2</span>], <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">1</span>)));
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<span class="macro">assert_eq!</span>(cursor.next_boundary(<span class="kw-2">&</span>s[..<span class="number">2</span>], <span class="number">0</span>), <span class="prelude-val">Err</span>(GraphemeIncomplete::NextChunk));
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<span class="macro">assert_eq!</span>(cursor.next_boundary(<span class="kw-2">&</span>s[<span class="number">2</span>..<span class="number">4</span>], <span class="number">2</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">2</span>)));
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<span class="macro">assert_eq!</span>(cursor.next_boundary(<span class="kw-2">&</span>s[<span class="number">2</span>..<span class="number">4</span>], <span class="number">2</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">3</span>)));
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<span class="macro">assert_eq!</span>(cursor.next_boundary(<span class="kw-2">&</span>s[<span class="number">2</span>..<span class="number">4</span>], <span class="number">2</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">4</span>)));
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<span class="macro">assert_eq!</span>(cursor.next_boundary(<span class="kw-2">&</span>s[<span class="number">2</span>..<span class="number">4</span>], <span class="number">2</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">None</span>));</code></pre></div>
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</div></details><details class="toggle method-toggle" open><summary><section id="method.prev_boundary" class="method"><a class="src rightside" href="../src/unicode_segmentation/grapheme.rs.html#776-836">Source</a><h4 class="code-header">pub fn <a href="#method.prev_boundary" class="fn">prev_boundary</a>(
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&mut self,
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chunk: &<a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.str.html">str</a>,
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chunk_start: <a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.usize.html">usize</a>,
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) -> <a class="enum" href="https://doc.rust-lang.org/1.84.0/core/result/enum.Result.html" title="enum core::result::Result">Result</a><<a class="enum" href="https://doc.rust-lang.org/1.84.0/core/option/enum.Option.html" title="enum core::option::Option">Option</a><<a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.usize.html">usize</a>>, <a class="enum" href="enum.GraphemeIncomplete.html" title="enum unicode_segmentation::GraphemeIncomplete">GraphemeIncomplete</a>></h4></section></summary><div class="docblock"><p>Find the previous boundary after the current cursor position. Only a part
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of the string need be supplied. If the chunk is incomplete, then this
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method might return <code>GraphemeIncomplete::PreContext</code> or
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<code>GraphemeIncomplete::PrevChunk</code>. In the former case, the caller should
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call <code>provide_context</code> with the requested chunk, then retry. In the
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latter case, the caller should provide the chunk preceding the one
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given, then retry.</p>
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<p>See <code>is_boundary</code> for expectations on the provided chunk.</p>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">let </span>flags = <span class="string">"\u{1F1F7}\u{1F1F8}\u{1F1EE}\u{1F1F4}"</span>;
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<span class="kw">let </span><span class="kw-2">mut </span>cursor = GraphemeCursor::new(<span class="number">12</span>, flags.len(), <span class="bool-val">false</span>);
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<span class="macro">assert_eq!</span>(cursor.prev_boundary(flags, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">8</span>)));
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<span class="macro">assert_eq!</span>(cursor.prev_boundary(flags, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">0</span>)));
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<span class="macro">assert_eq!</span>(cursor.prev_boundary(flags, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">None</span>));</code></pre></div>
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<p>And an example that uses partial strings (note the exact return is not
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guaranteed, and may be <code>PrevChunk</code> or <code>PreContext</code> arbitrarily):</p>
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<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">let </span>s = <span class="string">"abcd"</span>;
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<span class="kw">let </span><span class="kw-2">mut </span>cursor = GraphemeCursor::new(<span class="number">4</span>, s.len(), <span class="bool-val">false</span>);
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<span class="macro">assert_eq!</span>(cursor.prev_boundary(<span class="kw-2">&</span>s[<span class="number">2</span>..<span class="number">4</span>], <span class="number">2</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">3</span>)));
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<span class="macro">assert_eq!</span>(cursor.prev_boundary(<span class="kw-2">&</span>s[<span class="number">2</span>..<span class="number">4</span>], <span class="number">2</span>), <span class="prelude-val">Err</span>(GraphemeIncomplete::PrevChunk));
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<span class="macro">assert_eq!</span>(cursor.prev_boundary(<span class="kw-2">&</span>s[<span class="number">0</span>..<span class="number">2</span>], <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">2</span>)));
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<span class="macro">assert_eq!</span>(cursor.prev_boundary(<span class="kw-2">&</span>s[<span class="number">0</span>..<span class="number">2</span>], <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">1</span>)));
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<span class="macro">assert_eq!</span>(cursor.prev_boundary(<span class="kw-2">&</span>s[<span class="number">0</span>..<span class="number">2</span>], <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">0</span>)));
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<span class="macro">assert_eq!</span>(cursor.prev_boundary(<span class="kw-2">&</span>s[<span class="number">0</span>..<span class="number">2</span>], <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">None</span>));</code></pre></div>
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</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-GraphemeCursor" class="impl"><a class="src rightside" href="../src/unicode_segmentation/grapheme.rs.html#187">Source</a><a href="#impl-Clone-for-GraphemeCursor" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/clone/trait.Clone.html" title="trait core::clone::Clone">Clone</a> for <a class="struct" href="struct.GraphemeCursor.html" title="struct unicode_segmentation::GraphemeCursor">GraphemeCursor</a></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/unicode_segmentation/grapheme.rs.html#187">Source</a><a href="#method.clone" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.84.0/core/clone/trait.Clone.html#tymethod.clone" class="fn">clone</a>(&self) -> <a class="struct" href="struct.GraphemeCursor.html" title="struct unicode_segmentation::GraphemeCursor">GraphemeCursor</a></h4></section></summary><div class='docblock'>Returns a copy of the value. <a href="https://doc.rust-lang.org/1.84.0/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"><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/1.84.0/src/core/clone.rs.html#174">Source</a></span><a href="#method.clone_from" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.84.0/core/clone/trait.Clone.html#method.clone_from" class="fn">clone_from</a>(&mut self, source: &Self)</h4></section></summary><div class='docblock'>Performs copy-assignment from <code>source</code>. <a href="https://doc.rust-lang.org/1.84.0/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-GraphemeCursor" class="impl"><a class="src rightside" href="../src/unicode_segmentation/grapheme.rs.html#187">Source</a><a href="#impl-Debug-for-GraphemeCursor" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> for <a class="struct" href="struct.GraphemeCursor.html" title="struct unicode_segmentation::GraphemeCursor">GraphemeCursor</a></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/unicode_segmentation/grapheme.rs.html#187">Source</a><a href="#method.fmt" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.84.0/core/fmt/trait.Debug.html#tymethod.fmt" class="fn">fmt</a>(&self, f: &mut <a class="struct" href="https://doc.rust-lang.org/1.84.0/core/fmt/struct.Formatter.html" title="struct core::fmt::Formatter">Formatter</a><'_>) -> <a class="type" href="https://doc.rust-lang.org/1.84.0/core/fmt/type.Result.html" title="type core::fmt::Result">Result</a></h4></section></summary><div class='docblock'>Formats the value using the given formatter. <a href="https://doc.rust-lang.org/1.84.0/core/fmt/trait.Debug.html#tymethod.fmt">Read more</a></div></details></div></details></div><h2 id="synthetic-implementations" class="section-header">Auto Trait Implementations<a href="#synthetic-implementations" class="anchor">§</a></h2><div id="synthetic-implementations-list"><section id="impl-Freeze-for-GraphemeCursor" class="impl"><a href="#impl-Freeze-for-GraphemeCursor" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/marker/trait.Freeze.html" title="trait core::marker::Freeze">Freeze</a> for <a class="struct" href="struct.GraphemeCursor.html" title="struct unicode_segmentation::GraphemeCursor">GraphemeCursor</a></h3></section><section id="impl-RefUnwindSafe-for-GraphemeCursor" class="impl"><a href="#impl-RefUnwindSafe-for-GraphemeCursor" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/panic/unwind_safe/trait.RefUnwindSafe.html" title="trait core::panic::unwind_safe::RefUnwindSafe">RefUnwindSafe</a> for <a class="struct" href="struct.GraphemeCursor.html" title="struct unicode_segmentation::GraphemeCursor">GraphemeCursor</a></h3></section><section id="impl-Send-for-GraphemeCursor" class="impl"><a href="#impl-Send-for-GraphemeCursor" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> for <a class="struct" href="struct.GraphemeCursor.html" title="struct unicode_segmentation::GraphemeCursor">GraphemeCursor</a></h3></section><section id="impl-Sync-for-GraphemeCursor" class="impl"><a href="#impl-Sync-for-GraphemeCursor" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> for <a class="struct" href="struct.GraphemeCursor.html" title="struct unicode_segmentation::GraphemeCursor">GraphemeCursor</a></h3></section><section id="impl-Unpin-for-GraphemeCursor" class="impl"><a href="#impl-Unpin-for-GraphemeCursor" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/marker/trait.Unpin.html" title="trait core::marker::Unpin">Unpin</a> for <a class="struct" href="struct.GraphemeCursor.html" title="struct unicode_segmentation::GraphemeCursor">GraphemeCursor</a></h3></section><section id="impl-UnwindSafe-for-GraphemeCursor" class="impl"><a href="#impl-UnwindSafe-for-GraphemeCursor" class="anchor">§</a><h3 class="code-header">impl <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/panic/unwind_safe/trait.UnwindSafe.html" title="trait core::panic::unwind_safe::UnwindSafe">UnwindSafe</a> for <a class="struct" href="struct.GraphemeCursor.html" title="struct unicode_segmentation::GraphemeCursor">GraphemeCursor</a></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/1.84.0/src/core/any.rs.html#138">Source</a><a href="#impl-Any-for-T" class="anchor">§</a><h3 class="code-header">impl<T> <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/any/trait.Any.html" title="trait core::any::Any">Any</a> for T<div class="where">where
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T: 'static + ?<a class="trait" href="https://doc.rust-lang.org/1.84.0/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.type_id" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.84.0/src/core/any.rs.html#139">Source</a><a href="#method.type_id" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.84.0/core/any/trait.Any.html#tymethod.type_id" class="fn">type_id</a>(&self) -> <a class="struct" href="https://doc.rust-lang.org/1.84.0/core/any/struct.TypeId.html" title="struct core::any::TypeId">TypeId</a></h4></section></summary><div class='docblock'>Gets the <code>TypeId</code> of <code>self</code>. <a href="https://doc.rust-lang.org/1.84.0/core/any/trait.Any.html#tymethod.type_id">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-Borrow%3CT%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.84.0/src/core/borrow.rs.html#209">Source</a><a href="#impl-Borrow%3CT%3E-for-T" class="anchor">§</a><h3 class="code-header">impl<T> <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/borrow/trait.Borrow.html" title="trait core::borrow::Borrow">Borrow</a><T> for T<div class="where">where
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T: ?<a class="trait" href="https://doc.rust-lang.org/1.84.0/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.borrow" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.84.0/src/core/borrow.rs.html#211">Source</a><a href="#method.borrow" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.84.0/core/borrow/trait.Borrow.html#tymethod.borrow" class="fn">borrow</a>(&self) -> <a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.reference.html">&T</a></h4></section></summary><div class='docblock'>Immutably borrows from an owned value. <a href="https://doc.rust-lang.org/1.84.0/core/borrow/trait.Borrow.html#tymethod.borrow">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-BorrowMut%3CT%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.84.0/src/core/borrow.rs.html#217">Source</a><a href="#impl-BorrowMut%3CT%3E-for-T" class="anchor">§</a><h3 class="code-header">impl<T> <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/borrow/trait.BorrowMut.html" title="trait core::borrow::BorrowMut">BorrowMut</a><T> for T<div class="where">where
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T: ?<a class="trait" href="https://doc.rust-lang.org/1.84.0/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.borrow_mut" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.84.0/src/core/borrow.rs.html#218">Source</a><a href="#method.borrow_mut" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.84.0/core/borrow/trait.BorrowMut.html#tymethod.borrow_mut" class="fn">borrow_mut</a>(&mut self) -> <a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.reference.html">&mut T</a></h4></section></summary><div class='docblock'>Mutably borrows from an owned value. <a href="https://doc.rust-lang.org/1.84.0/core/borrow/trait.BorrowMut.html#tymethod.borrow_mut">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-CloneToUninit-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.84.0/src/core/clone.rs.html#273">Source</a><a href="#impl-CloneToUninit-for-T" class="anchor">§</a><h3 class="code-header">impl<T> <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/clone/trait.CloneToUninit.html" title="trait core::clone::CloneToUninit">CloneToUninit</a> for T<div class="where">where
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T: <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/clone/trait.Clone.html" title="trait core::clone::Clone">Clone</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.clone_to_uninit" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.84.0/src/core/clone.rs.html#275">Source</a><a href="#method.clone_to_uninit" class="anchor">§</a><h4 class="code-header">unsafe fn <a href="https://doc.rust-lang.org/1.84.0/core/clone/trait.CloneToUninit.html#tymethod.clone_to_uninit" class="fn">clone_to_uninit</a>(&self, dst: <a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.pointer.html">*mut </a><a class="primitive" href="https://doc.rust-lang.org/1.84.0/core/primitive.u8.html">u8</a>)</h4></section></summary><span class="item-info"><div class="stab unstable"><span class="emoji">🔬</span><span>This is a nightly-only experimental API. (<code>clone_to_uninit</code>)</span></div></span><div class='docblock'>Performs copy-assignment from <code>self</code> to <code>dst</code>. <a href="https://doc.rust-lang.org/1.84.0/core/clone/trait.CloneToUninit.html#tymethod.clone_to_uninit">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-From%3CT%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.84.0/src/core/convert/mod.rs.html#765">Source</a><a href="#impl-From%3CT%3E-for-T" class="anchor">§</a><h3 class="code-header">impl<T> <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/convert/trait.From.html" title="trait core::convert::From">From</a><T> for T</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.from" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.84.0/src/core/convert/mod.rs.html#768">Source</a><a href="#method.from" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.84.0/core/convert/trait.From.html#tymethod.from" class="fn">from</a>(t: T) -> T</h4></section></summary><div class="docblock"><p>Returns the argument unchanged.</p>
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</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/1.84.0/src/core/convert/mod.rs.html#748-750">Source</a><a href="#impl-Into%3CU%3E-for-T" class="anchor">§</a><h3 class="code-header">impl<T, U> <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/convert/trait.Into.html" title="trait core::convert::Into">Into</a><U> for T<div class="where">where
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U: <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/convert/trait.From.html" title="trait core::convert::From">From</a><T>,</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/1.84.0/src/core/convert/mod.rs.html#758">Source</a><a href="#method.into" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.84.0/core/convert/trait.Into.html#tymethod.into" class="fn">into</a>(self) -> U</h4></section></summary><div class="docblock"><p>Calls <code>U::from(self)</code>.</p>
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<p>That is, this conversion is whatever the implementation of
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<code><a href="https://doc.rust-lang.org/1.84.0/core/convert/trait.From.html" title="trait core::convert::From">From</a><T> for U</code> chooses to do.</p>
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</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/1.84.0/src/core/convert/mod.rs.html#805-807">Source</a><a href="#impl-TryFrom%3CU%3E-for-T" class="anchor">§</a><h3 class="code-header">impl<T, U> <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a><U> for T<div class="where">where
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U: <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/convert/trait.Into.html" title="trait core::convert::Into">Into</a><T>,</div></h3></section></summary><div class="impl-items"><details class="toggle" open><summary><section id="associatedtype.Error-1" class="associatedtype trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.84.0/src/core/convert/mod.rs.html#809">Source</a><a href="#associatedtype.Error-1" class="anchor">§</a><h4 class="code-header">type <a href="https://doc.rust-lang.org/1.84.0/core/convert/trait.TryFrom.html#associatedtype.Error" class="associatedtype">Error</a> = <a class="enum" href="https://doc.rust-lang.org/1.84.0/core/convert/enum.Infallible.html" title="enum core::convert::Infallible">Infallible</a></h4></section></summary><div class='docblock'>The type returned in the event of a conversion error.</div></details><details class="toggle method-toggle" open><summary><section id="method.try_from" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.84.0/src/core/convert/mod.rs.html#812">Source</a><a href="#method.try_from" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.84.0/core/convert/trait.TryFrom.html#tymethod.try_from" class="fn">try_from</a>(value: U) -> <a class="enum" href="https://doc.rust-lang.org/1.84.0/core/result/enum.Result.html" title="enum core::result::Result">Result</a><T, <T as <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a><U>>::<a class="associatedtype" href="https://doc.rust-lang.org/1.84.0/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a>></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/1.84.0/src/core/convert/mod.rs.html#790-792">Source</a><a href="#impl-TryInto%3CU%3E-for-T" class="anchor">§</a><h3 class="code-header">impl<T, U> <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/convert/trait.TryInto.html" title="trait core::convert::TryInto">TryInto</a><U> for T<div class="where">where
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U: <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a><T>,</div></h3></section></summary><div class="impl-items"><details class="toggle" open><summary><section id="associatedtype.Error" class="associatedtype trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.84.0/src/core/convert/mod.rs.html#794">Source</a><a href="#associatedtype.Error" class="anchor">§</a><h4 class="code-header">type <a href="https://doc.rust-lang.org/1.84.0/core/convert/trait.TryInto.html#associatedtype.Error" class="associatedtype">Error</a> = <U as <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a><T>>::<a class="associatedtype" href="https://doc.rust-lang.org/1.84.0/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a></h4></section></summary><div class='docblock'>The type returned in the event of a conversion error.</div></details><details class="toggle method-toggle" open><summary><section id="method.try_into" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.84.0/src/core/convert/mod.rs.html#797">Source</a><a href="#method.try_into" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.84.0/core/convert/trait.TryInto.html#tymethod.try_into" class="fn">try_into</a>(self) -> <a class="enum" href="https://doc.rust-lang.org/1.84.0/core/result/enum.Result.html" title="enum core::result::Result">Result</a><U, <U as <a class="trait" href="https://doc.rust-lang.org/1.84.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a><T>>::<a class="associatedtype" href="https://doc.rust-lang.org/1.84.0/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a>></h4></section></summary><div class='docblock'>Performs the conversion.</div></details></div></details></div></section></div></main></body></html> |