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<h1 class='fqn'><span class='in-band'>Struct <a href='index.html'>regex</a>::<wbr><a class='struct' href=''>Captures</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'>−</span>]
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</span><a class='srclink' href='../src/regex/re_unicode.rs.html#927-931' title='goto source code'>[src]</a></span></h1>
<pre class='rust struct'>pub struct Captures<'t> { /* fields omitted */ }</pre><div class='docblock'><p>Captures represents a group of captured strings for a single match.</p>
<p>The 0th capture always corresponds to the entire match. Each subsequent
index corresponds to the next capture group in the regex. If a capture
group is named, then the matched string is <em>also</em> available via the <code>name</code>
method. (Note that the 0th capture is always unnamed and so must be
accessed with the <code>get</code> method.)</p>
<p>Positions returned from a capture group are always byte indices.</p>
<p><code>'t</code> is the lifetime of the matched text.</p>
</div><h2 id='methods'>Methods</h2><h3 class='impl'><span class='in-band'><code>impl<'t> <a class='struct' href='../regex/struct.Captures.html' title='regex::Captures'>Captures</a><'t></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/regex/re_unicode.rs.html#933-1003' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.get' class='method'><span id='get.v' class='invisible'><code>fn <a href='#method.get' class='fnname'>get</a>(&self, i: <a class='primitive' href='https://doc.rust-lang.org/nightly/std/primitive.usize.html'>usize</a>) -> <a class='enum' href='https://doc.rust-lang.org/nightly/core/option/enum.Option.html' title='core::option::Option'>Option</a><<a class='struct' href='../regex/struct.Match.html' title='regex::Match'>Match</a><'t>></code></span></h4>
<div class='docblock'><p>Returns the match associated with the capture group at index <code>i</code>. If
<code>i</code> does not correspond to a capture group, or if the capture group
did not participate in the match, then <code>None</code> is returned.</p>
<h1 id='examples' class='section-header'><a href='#examples'>Examples</a></h1>
<p>Get the text of the match with a default of an empty string if this
group didn't participate in the match:</p>
<pre class='rust rust-example-rendered'>
<span class='kw'>let</span> <span class='ident'>re</span> <span class='op'>=</span> <span class='ident'>Regex</span>::<span class='ident'>new</span>(<span class='string'>r"[a-z]+(?:([0-9]+)|([A-Z]+))"</span>).<span class='ident'>unwrap</span>();
<span class='kw'>let</span> <span class='ident'>caps</span> <span class='op'>=</span> <span class='ident'>re</span>.<span class='ident'>captures</span>(<span class='string'>"abc123"</span>).<span class='ident'>unwrap</span>();
<span class='kw'>let</span> <span class='ident'>text1</span> <span class='op'>=</span> <span class='ident'>caps</span>.<span class='ident'>get</span>(<span class='number'>1</span>).<span class='ident'>map_or</span>(<span class='string'>""</span>, <span class='op'>|</span><span class='ident'>m</span><span class='op'>|</span> <span class='ident'>m</span>.<span class='ident'>as_str</span>());
<span class='kw'>let</span> <span class='ident'>text2</span> <span class='op'>=</span> <span class='ident'>caps</span>.<span class='ident'>get</span>(<span class='number'>2</span>).<span class='ident'>map_or</span>(<span class='string'>""</span>, <span class='op'>|</span><span class='ident'>m</span><span class='op'>|</span> <span class='ident'>m</span>.<span class='ident'>as_str</span>());
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>text1</span>, <span class='string'>"123"</span>);
<span class='macro'>assert_eq</span><span class='macro'>!</span>(<span class='ident'>text2</span>, <span class='string'>""</span>);</pre>
</div><h4 id='method.name' class='method'><span id='name.v' class='invisible'><code>fn <a href='#method.name' class='fnname'>name</a>(&self, name: &<a class='primitive' href='https://doc.rust-lang.org/nightly/std/primitive.str.html'>str</a>) -> <a class='enum' href='https://doc.rust-lang.org/nightly/core/option/enum.Option.html' title='core::option::Option'>Option</a><<a class='struct' href='../regex/struct.Match.html' title='regex::Match'>Match</a><'t>></code></span></h4>
<div class='docblock'><p>Returns the match for the capture group named <code>name</code>. If <code>name</code> isn't a
valid capture group or didn't match anything, then <code>None</code> is returned.</p>
</div><h4 id='method.iter' class='method'><span id='iter.v' class='invisible'><code>fn <a href='#method.iter' class='fnname'>iter</a><'c>(&'c self) -> <a class='struct' href='../regex/struct.SubCaptureMatches.html' title='regex::SubCaptureMatches'>SubCaptureMatches</a><'c, 't></code></span></h4>
<div class='docblock'><p>An iterator that yields all capturing matches in the order in which
they appear in the regex. If a particular capture group didn't
participate in the match, then <code>None</code> is yielded for that capture.</p>
<p>The first match always corresponds to the overall match of the regex.</p>
</div><h4 id='method.expand' class='method'><span id='expand.v' class='invisible'><code>fn <a href='#method.expand' class='fnname'>expand</a>(&self, replacement: &<a class='primitive' href='https://doc.rust-lang.org/nightly/std/primitive.str.html'>str</a>, dst: &mut <a class='struct' href='https://doc.rust-lang.org/nightly/collections/string/struct.String.html' title='collections::string::String'>String</a>)</code></span></h4>
<div class='docblock'><p>Expands all instances of <code>$name</code> in <code>text</code> to the corresponding capture
group <code>name</code>, and writes them to the <code>dst</code> buffer given.</p>
<p><code>name</code> may be an integer corresponding to the index of the
capture group (counted by order of opening parenthesis where <code>0</code> is the
entire match) or it can be a name (consisting of letters, digits or
underscores) corresponding to a named capture group.</p>
<p>If <code>name</code> isn't a valid capture group (whether the name doesn't exist
or isn't a valid index), then it is replaced with the empty string.</p>
<p>The longest possible name is used. e.g., <code>$1a</code> looks up the capture
group named <code>1a</code> and not the capture group at index <code>1</code>. To exert more
precise control over the name, use braces, e.g., <code>${1}a</code>.</p>
<p>To write a literal <code>$</code> use <code>$$</code>.</p>
</div><h4 id='method.len' class='method'><span id='len.v' class='invisible'><code>fn <a href='#method.len' class='fnname'>len</a>(&self) -> <a class='primitive' href='https://doc.rust-lang.org/nightly/std/primitive.usize.html'>usize</a></code></span></h4>
<div class='docblock'><p>Returns the number of captured groups.</p>
<p>This is always at least <code>1</code>, since every regex has at least one capture
group that corresponds to the full match.</p>
</div></div><h2 id='implementations'>Trait Implementations</h2><h3 class='impl'><span class='in-band'><code>impl<'t> <a class='trait' href='https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html' title='core::fmt::Debug'>Debug</a> for <a class='struct' href='../regex/struct.Captures.html' title='regex::Captures'>Captures</a><'t></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/regex/re_unicode.rs.html#1005-1009' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.fmt' class='method'><span id='fmt.v' class='invisible'><code>fn <a href='https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html#tymethod.fmt' class='fnname'>fmt</a>(&self, f: &mut <a class='struct' href='https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html' title='core::fmt::Formatter'>Formatter</a>) -> <a class='type' href='https://doc.rust-lang.org/nightly/core/fmt/type.Result.html' title='core::fmt::Result'>Result</a></code></span></h4>
<div class='docblock'><p>Formats the value using the given formatter.</p>
</div></div><h3 class='impl'><span class='in-band'><code>impl<'t> <a class='trait' href='https://doc.rust-lang.org/nightly/core/ops/trait.Index.html' title='core::ops::Index'>Index</a><<a class='primitive' href='https://doc.rust-lang.org/nightly/std/primitive.usize.html'>usize</a>> for <a class='struct' href='../regex/struct.Captures.html' title='regex::Captures'>Captures</a><'t></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/regex/re_unicode.rs.html#1043-1050' title='goto source code'>[src]</a></span></h3>
<div class='docblock'><p>Get a group by index.</p>
<p><code>'t</code> is the lifetime of the matched text.</p>
<p>The text can't outlive the <code>Captures</code> object if this method is
used, because of how <code>Index</code> is defined (normally <code>a[i]</code> is part
of <code>a</code> and can't outlive it); to do that, use <code>get()</code> instead.</p>
<h1 id='panics' class='section-header'><a href='#panics'>Panics</a></h1>
<p>If there is no group at the given index.</p>
</div><div class='impl-items'><h4 id='associatedtype.Output' class='type'><span id='Output.t' class='invisible'><code>type <a href='https://doc.rust-lang.org/nightly/core/ops/trait.Index.html#associatedtype.Output' class='type'>Output</a> = <a class='primitive' href='https://doc.rust-lang.org/nightly/std/primitive.str.html'>str</a></code></span></h4>
<div class='docblock'><p>The returned type after indexing</p>
</div><h4 id='method.index' class='method'><span id='index.v' class='invisible'><code>fn <a href='https://doc.rust-lang.org/nightly/core/ops/trait.Index.html#tymethod.index' class='fnname'>index</a>(&self, i: <a class='primitive' href='https://doc.rust-lang.org/nightly/std/primitive.usize.html'>usize</a>) -> &<a class='primitive' href='https://doc.rust-lang.org/nightly/std/primitive.str.html'>str</a></code></span></h4>
<div class='docblock'><p>The method for the indexing (<code>container[index]</code>) operation</p>
</div></div><h3 class='impl'><span class='in-band'><code>impl<'t, 'i> <a class='trait' href='https://doc.rust-lang.org/nightly/core/ops/trait.Index.html' title='core::ops::Index'>Index</a><&'i <a class='primitive' href='https://doc.rust-lang.org/nightly/std/primitive.str.html'>str</a>> for <a class='struct' href='../regex/struct.Captures.html' title='regex::Captures'>Captures</a><'t></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/regex/re_unicode.rs.html#1064-1071' title='goto source code'>[src]</a></span></h3>
<div class='docblock'><p>Get a group by name.</p>
<p><code>'t</code> is the lifetime of the matched text and <code>'i</code> is the lifetime
of the group name (the index).</p>
<p>The text can't outlive the <code>Captures</code> object if this method is
used, because of how <code>Index</code> is defined (normally <code>a[i]</code> is part
of <code>a</code> and can't outlive it); to do that, use <code>name</code> instead.</p>
<h1 id='panics-1' class='section-header'><a href='#panics-1'>Panics</a></h1>
<p>If there is no group named by the given value.</p>
</div><div class='impl-items'><h4 id='associatedtype.Output-1' class='type'><span id='Output.t-1' class='invisible'><code>type <a href='https://doc.rust-lang.org/nightly/core/ops/trait.Index.html#associatedtype.Output' class='type'>Output</a> = <a class='primitive' href='https://doc.rust-lang.org/nightly/std/primitive.str.html'>str</a></code></span></h4>
<div class='docblock'><p>The returned type after indexing</p>
</div><h4 id='method.index-1' class='method'><span id='index.v-1' class='invisible'><code>fn <a href='https://doc.rust-lang.org/nightly/core/ops/trait.Index.html#tymethod.index' class='fnname'>index</a><'a>(&'a self, name: &'i <a class='primitive' href='https://doc.rust-lang.org/nightly/std/primitive.str.html'>str</a>) -> &'a <a class='primitive' href='https://doc.rust-lang.org/nightly/std/primitive.str.html'>str</a></code></span></h4>
<div class='docblock'><p>The method for the indexing (<code>container[index]</code>) operation</p>
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