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<p class='location'>Struct GraphemeCursor</p><div class="block items"><ul><li><a href="#methods">Methods</a></li><li><a href="#implementations">Trait Implementations</a></li></ul></div><p class='location'><a href='index.html'>unicode_segmentation</a></p><script>window.sidebarCurrent = {name: 'GraphemeCursor', ty: 'struct', relpath: ''};</script><script defer src="sidebar-items.js"></script>
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<h1 class='fqn'><span class='in-band'>Struct <a href='index.html'>unicode_segmentation</a>::<wbr><a class="struct" href=''>GraphemeCursor</a></span><span class='out-of-band'><span id='render-detail'>
<a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">
[<span class='inner'>&#x2212;</span>]
</a>
</span><a class='srclink' href='../src/unicode_segmentation/grapheme.rs.html#157-181' title='goto source code'>[src]</a></span></h1>
<pre class='rust struct'>pub struct GraphemeCursor { /* fields omitted */ }</pre><div class='docblock'><p>Cursor-based segmenter for grapheme clusters.</p>
</div>
<h2 id='methods' class='small-section-header'>
Methods<a href='#methods' class='anchor'></a>
</h2>
<h3 class='impl'><span class='in-band'><code>impl <a class="struct" href="../unicode_segmentation/struct.GraphemeCursor.html" title="struct unicode_segmentation::GraphemeCursor">GraphemeCursor</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/unicode_segmentation/grapheme.rs.html#252-661' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.new' class="method"><span id='new.v' class='invisible'><code>fn <a href='#method.new' class='fnname'>new</a>(offset: usize, len: usize, is_extended: bool) -&gt; <a class="struct" href="../unicode_segmentation/struct.GraphemeCursor.html" title="struct unicode_segmentation::GraphemeCursor">GraphemeCursor</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/unicode_segmentation/grapheme.rs.html#267-284' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Create a new cursor. The string and initial offset are given at creation
time, but the contents of the string are not. The <code>is_extended</code> parameter
controls whether extended grapheme clusters are selected.</p>
<p>The <code>offset</code> parameter must be on a codepoint boundary.</p>
<pre class="rust rust-example-rendered">
<span class="kw">let</span> <span class="ident">s</span> <span class="op">=</span> <span class="string">&quot;हिन्दी&quot;</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">legacy</span> <span class="op">=</span> <span class="ident">GraphemeCursor</span>::<span class="ident">new</span>(<span class="number">0</span>, <span class="ident">s</span>.<span class="ident">len</span>(), <span class="bool-val">false</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">legacy</span>.<span class="ident">next_boundary</span>(<span class="ident">s</span>, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="string">&quot;ह&quot;</span>.<span class="ident">len</span>())));
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">extended</span> <span class="op">=</span> <span class="ident">GraphemeCursor</span>::<span class="ident">new</span>(<span class="number">0</span>, <span class="ident">s</span>.<span class="ident">len</span>(), <span class="bool-val">true</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">extended</span>.<span class="ident">next_boundary</span>(<span class="ident">s</span>, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="string">&quot;हि&quot;</span>.<span class="ident">len</span>())));</pre>
</div><h4 id='method.set_cursor' class="method"><span id='set_cursor.v' class='invisible'><code>fn <a href='#method.set_cursor' class='fnname'>set_cursor</a>(&amp;mut self, offset: usize)</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/unicode_segmentation/grapheme.rs.html#298-311' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Set the cursor to a new location in the same string.</p>
<pre class="rust rust-example-rendered">
<span class="kw">let</span> <span class="ident">s</span> <span class="op">=</span> <span class="string">&quot;abcd&quot;</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">cursor</span> <span class="op">=</span> <span class="ident">GraphemeCursor</span>::<span class="ident">new</span>(<span class="number">0</span>, <span class="ident">s</span>.<span class="ident">len</span>(), <span class="bool-val">false</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">cur_cursor</span>(), <span class="number">0</span>);
<span class="ident">cursor</span>.<span class="ident">set_cursor</span>(<span class="number">2</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">cur_cursor</span>(), <span class="number">2</span>);</pre>
</div><h4 id='method.cur_cursor' class="method"><span id='cur_cursor.v' class='invisible'><code>fn <a href='#method.cur_cursor' class='fnname'>cur_cursor</a>(&amp;self) -&gt; usize</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/unicode_segmentation/grapheme.rs.html#326-328' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>The current offset of the cursor. Equal to the last value provided to
<code>new()</code> or <code>set_cursor()</code>, or returned from <code>next_boundary()</code> or
<code>prev_boundary()</code>.</p>
<pre class="rust rust-example-rendered">
<span class="comment">// Two flags (🇷🇸🇮🇴), each flag is two RIS codepoints, each RIS is 4 bytes.</span>
<span class="kw">let</span> <span class="ident">flags</span> <span class="op">=</span> <span class="string">&quot;\u{1F1F7}\u{1F1F8}\u{1F1EE}\u{1F1F4}&quot;</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">cursor</span> <span class="op">=</span> <span class="ident">GraphemeCursor</span>::<span class="ident">new</span>(<span class="number">4</span>, <span class="ident">flags</span>.<span class="ident">len</span>(), <span class="bool-val">false</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">cur_cursor</span>(), <span class="number">4</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">next_boundary</span>(<span class="ident">flags</span>, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">8</span>)));
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">cur_cursor</span>(), <span class="number">8</span>);</pre>
</div><h4 id='method.provide_context' class="method"><span id='provide_context.v' class='invisible'><code>fn <a href='#method.provide_context' class='fnname'>provide_context</a>(&amp;mut self, chunk: &amp;str, chunk_start: usize)</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/unicode_segmentation/grapheme.rs.html#349-365' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Provide additional pre-context when it is needed to decide a boundary.
The end of the chunk must coincide with the value given in the
<code>GraphemeIncomplete::PreContext</code> request.</p>
<pre class="rust rust-example-rendered">
<span class="kw">let</span> <span class="ident">flags</span> <span class="op">=</span> <span class="string">&quot;\u{1F1F7}\u{1F1F8}\u{1F1EE}\u{1F1F4}&quot;</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">cursor</span> <span class="op">=</span> <span class="ident">GraphemeCursor</span>::<span class="ident">new</span>(<span class="number">8</span>, <span class="ident">flags</span>.<span class="ident">len</span>(), <span class="bool-val">false</span>);
<span class="comment">// Not enough pre-context to decide if there&#39;s a boundary between the two flags.</span>
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">is_boundary</span>(<span class="kw-2">&amp;</span><span class="ident">flags</span>[<span class="number">8</span>..], <span class="number">8</span>), <span class="prelude-val">Err</span>(<span class="ident">GraphemeIncomplete</span>::<span class="ident">PreContext</span>(<span class="number">8</span>)));
<span class="comment">// Provide one more Regional Indicator Symbol of pre-context</span>
<span class="ident">cursor</span>.<span class="ident">provide_context</span>(<span class="kw-2">&amp;</span><span class="ident">flags</span>[<span class="number">4</span>..<span class="number">8</span>], <span class="number">4</span>);
<span class="comment">// Still not enough context to decide.</span>
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">is_boundary</span>(<span class="kw-2">&amp;</span><span class="ident">flags</span>[<span class="number">8</span>..], <span class="number">8</span>), <span class="prelude-val">Err</span>(<span class="ident">GraphemeIncomplete</span>::<span class="ident">PreContext</span>(<span class="number">4</span>)));
<span class="comment">// Provide additional requested context.</span>
<span class="ident">cursor</span>.<span class="ident">provide_context</span>(<span class="kw-2">&amp;</span><span class="ident">flags</span>[<span class="number">0</span>..<span class="number">4</span>], <span class="number">0</span>);
<span class="comment">// That&#39;s enough to decide (it always is when context goes to the start of the string)</span>
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">is_boundary</span>(<span class="kw-2">&amp;</span><span class="ident">flags</span>[<span class="number">8</span>..], <span class="number">8</span>), <span class="prelude-val">Ok</span>(<span class="bool-val">true</span>));</pre>
</div><h4 id='method.is_boundary' class="method"><span id='is_boundary.v' class='invisible'><code>fn <a href='#method.is_boundary' class='fnname'>is_boundary</a>(<br>&nbsp;&nbsp;&nbsp;&nbsp;&amp;mut self, <br>&nbsp;&nbsp;&nbsp;&nbsp;chunk: &amp;str, <br>&nbsp;&nbsp;&nbsp;&nbsp;chunk_start: usize<br>) -&gt; <a class="enum" href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;bool, <a class="enum" href="../unicode_segmentation/enum.GraphemeIncomplete.html" title="enum unicode_segmentation::GraphemeIncomplete">GraphemeIncomplete</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/unicode_segmentation/grapheme.rs.html#456-512' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Determine whether the current cursor location is a grapheme cluster boundary.
Only a part of the string need be supplied. If <code>chunk_start</code> is nonzero or
the length of <code>chunk</code> is not equal to <code>len</code> on creation, then this method
may return <code>GraphemeIncomplete::PreContext</code>. The caller should then
call <code>provide_context</code> with the requested chunk, then retry calling this
method.</p>
<p>For partial chunks, if the cursor is not at the beginning or end of the
string, the chunk should contain at least the codepoint following the cursor.
If the string is nonempty, the chunk must be nonempty.</p>
<p>All calls should have consistent chunk contents (ie, if a chunk provides
content for a given slice, all further chunks covering that slice must have
the same content for it).</p>
<pre class="rust rust-example-rendered">
<span class="kw">let</span> <span class="ident">flags</span> <span class="op">=</span> <span class="string">&quot;\u{1F1F7}\u{1F1F8}\u{1F1EE}\u{1F1F4}&quot;</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">cursor</span> <span class="op">=</span> <span class="ident">GraphemeCursor</span>::<span class="ident">new</span>(<span class="number">8</span>, <span class="ident">flags</span>.<span class="ident">len</span>(), <span class="bool-val">false</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">is_boundary</span>(<span class="ident">flags</span>, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="bool-val">true</span>));
<span class="ident">cursor</span>.<span class="ident">set_cursor</span>(<span class="number">12</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">is_boundary</span>(<span class="ident">flags</span>, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="bool-val">false</span>));</pre>
</div><h4 id='method.next_boundary' class="method"><span id='next_boundary.v' class='invisible'><code>fn <a href='#method.next_boundary' class='fnname'>next_boundary</a>(<br>&nbsp;&nbsp;&nbsp;&nbsp;&amp;mut self, <br>&nbsp;&nbsp;&nbsp;&nbsp;chunk: &amp;str, <br>&nbsp;&nbsp;&nbsp;&nbsp;chunk_start: usize<br>) -&gt; <a class="enum" href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;<a class="enum" href="https://doc.rust-lang.org/nightly/core/option/enum.Option.html" title="enum core::option::Option">Option</a>&lt;usize&gt;, <a class="enum" href="../unicode_segmentation/enum.GraphemeIncomplete.html" title="enum unicode_segmentation::GraphemeIncomplete">GraphemeIncomplete</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/unicode_segmentation/grapheme.rs.html#546-587' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Find the next boundary after the current cursor position. Only a part of
the string need be supplied. If the chunk is incomplete, then this
method might return <code>GraphemeIncomplete::PreContext</code> or
<code>GraphemeIncomplete::NextChunk</code>. In the former case, the caller should
call <code>provide_context</code> with the requested chunk, then retry. In the
latter case, the caller should provide the chunk following the one
given, then retry.</p>
<p>See <code>is_boundary</code> for expectations on the provided chunk.</p>
<pre class="rust rust-example-rendered">
<span class="kw">let</span> <span class="ident">flags</span> <span class="op">=</span> <span class="string">&quot;\u{1F1F7}\u{1F1F8}\u{1F1EE}\u{1F1F4}&quot;</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">cursor</span> <span class="op">=</span> <span class="ident">GraphemeCursor</span>::<span class="ident">new</span>(<span class="number">4</span>, <span class="ident">flags</span>.<span class="ident">len</span>(), <span class="bool-val">false</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">next_boundary</span>(<span class="ident">flags</span>, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">8</span>)));
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">next_boundary</span>(<span class="ident">flags</span>, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">16</span>)));
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">next_boundary</span>(<span class="ident">flags</span>, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">None</span>));</pre>
<p>And an example that uses partial strings:</p>
<pre class="rust rust-example-rendered">
<span class="kw">let</span> <span class="ident">s</span> <span class="op">=</span> <span class="string">&quot;abcd&quot;</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">cursor</span> <span class="op">=</span> <span class="ident">GraphemeCursor</span>::<span class="ident">new</span>(<span class="number">0</span>, <span class="ident">s</span>.<span class="ident">len</span>(), <span class="bool-val">false</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">next_boundary</span>(<span class="kw-2">&amp;</span><span class="ident">s</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>)));
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">next_boundary</span>(<span class="kw-2">&amp;</span><span class="ident">s</span>[..<span class="number">2</span>], <span class="number">0</span>), <span class="prelude-val">Err</span>(<span class="ident">GraphemeIncomplete</span>::<span class="ident">NextChunk</span>));
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">next_boundary</span>(<span class="kw-2">&amp;</span><span class="ident">s</span>[<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>)));
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">next_boundary</span>(<span class="kw-2">&amp;</span><span class="ident">s</span>[<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>)));
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">next_boundary</span>(<span class="kw-2">&amp;</span><span class="ident">s</span>[<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>)));
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">next_boundary</span>(<span class="kw-2">&amp;</span><span class="ident">s</span>[<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>));</pre>
</div><h4 id='method.prev_boundary' class="method"><span id='prev_boundary.v' class='invisible'><code>fn <a href='#method.prev_boundary' class='fnname'>prev_boundary</a>(<br>&nbsp;&nbsp;&nbsp;&nbsp;&amp;mut self, <br>&nbsp;&nbsp;&nbsp;&nbsp;chunk: &amp;str, <br>&nbsp;&nbsp;&nbsp;&nbsp;chunk_start: usize<br>) -&gt; <a class="enum" href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;<a class="enum" href="https://doc.rust-lang.org/nightly/core/option/enum.Option.html" title="enum core::option::Option">Option</a>&lt;usize&gt;, <a class="enum" href="../unicode_segmentation/enum.GraphemeIncomplete.html" title="enum unicode_segmentation::GraphemeIncomplete">GraphemeIncomplete</a>&gt;</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/unicode_segmentation/grapheme.rs.html#622-660' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Find the previous boundary after the current cursor position. Only a part
of the string need be supplied. If the chunk is incomplete, then this
method might return <code>GraphemeIncomplete::PreContext</code> or
<code>GraphemeIncomplete::PrevChunk</code>. In the former case, the caller should
call <code>provide_context</code> with the requested chunk, then retry. In the
latter case, the caller should provide the chunk preceding the one
given, then retry.</p>
<p>See <code>is_boundary</code> for expectations on the provided chunk.</p>
<pre class="rust rust-example-rendered">
<span class="kw">let</span> <span class="ident">flags</span> <span class="op">=</span> <span class="string">&quot;\u{1F1F7}\u{1F1F8}\u{1F1EE}\u{1F1F4}&quot;</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">cursor</span> <span class="op">=</span> <span class="ident">GraphemeCursor</span>::<span class="ident">new</span>(<span class="number">12</span>, <span class="ident">flags</span>.<span class="ident">len</span>(), <span class="bool-val">false</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">prev_boundary</span>(<span class="ident">flags</span>, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">8</span>)));
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">prev_boundary</span>(<span class="ident">flags</span>, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(<span class="number">0</span>)));
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">prev_boundary</span>(<span class="ident">flags</span>, <span class="number">0</span>), <span class="prelude-val">Ok</span>(<span class="prelude-val">None</span>));</pre>
<p>And an example that uses partial strings (note the exact return is not
guaranteed, and may be <code>PrevChunk</code> or <code>PreContext</code> arbitrarily):</p>
<pre class="rust rust-example-rendered">
<span class="kw">let</span> <span class="ident">s</span> <span class="op">=</span> <span class="string">&quot;abcd&quot;</span>;
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">cursor</span> <span class="op">=</span> <span class="ident">GraphemeCursor</span>::<span class="ident">new</span>(<span class="number">4</span>, <span class="ident">s</span>.<span class="ident">len</span>(), <span class="bool-val">false</span>);
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">prev_boundary</span>(<span class="kw-2">&amp;</span><span class="ident">s</span>[<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>)));
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">prev_boundary</span>(<span class="kw-2">&amp;</span><span class="ident">s</span>[<span class="number">2</span>..<span class="number">4</span>], <span class="number">2</span>), <span class="prelude-val">Err</span>(<span class="ident">GraphemeIncomplete</span>::<span class="ident">PrevChunk</span>));
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">prev_boundary</span>(<span class="kw-2">&amp;</span><span class="ident">s</span>[<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>)));
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">prev_boundary</span>(<span class="kw-2">&amp;</span><span class="ident">s</span>[<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>)));
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">prev_boundary</span>(<span class="kw-2">&amp;</span><span class="ident">s</span>[<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>)));
<span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">cursor</span>.<span class="ident">prev_boundary</span>(<span class="kw-2">&amp;</span><span class="ident">s</span>[<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>));</pre>
</div></div>
<h2 id='implementations' class='small-section-header'>
Trait Implementations<a href='#implementations' class='anchor'></a>
</h2>
<h3 class='impl'><span class='in-band'><code>impl <a class="trait" href="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html" title="trait core::clone::Clone">Clone</a> for <a class="struct" href="../unicode_segmentation/struct.GraphemeCursor.html" title="struct unicode_segmentation::GraphemeCursor">GraphemeCursor</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/unicode_segmentation/grapheme.rs.html#156' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.clone' class="method"><span id='clone.v' class='invisible'><code>fn <a href='https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#tymethod.clone' class='fnname'>clone</a>(&amp;self) -&gt; <a class="struct" href="../unicode_segmentation/struct.GraphemeCursor.html" title="struct unicode_segmentation::GraphemeCursor">GraphemeCursor</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/unicode_segmentation/grapheme.rs.html#156' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Returns a copy of the value. <a href="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#tymethod.clone">Read more</a></p>
</div><h4 id='method.clone_from' class="method"><span id='clone_from.v' class='invisible'><code>fn <a href='https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#method.clone_from' class='fnname'>clone_from</a>(&amp;mut self, source: &amp;Self)</code></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.0.0'>1.0.0</div><a class='srclink' href='https://doc.rust-lang.org/nightly/src/core/clone.rs.html#112-114' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Performs copy-assignment from <code>source</code>. <a href="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#method.clone_from">Read more</a></p>
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