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diff --git a/doc/html/boost/xpressive/value.html b/doc/html/boost/xpressive/value.html index 84169c5cdf..1eace9bd04 100644 --- a/doc/html/boost/xpressive/value.html +++ b/doc/html/boost/xpressive/value.html @@ -3,7 +3,7 @@ <meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> <title>Struct template value</title> <link rel="stylesheet" href="../../../../doc/src/boostbook.css" type="text/css"> -<meta name="generator" content="DocBook XSL Stylesheets V1.76.1"> +<meta name="generator" content="DocBook XSL Stylesheets V1.78.1"> <link rel="home" href="../../index.html" title="The Boost C++ Libraries BoostBook Documentation Subset"> <link rel="up" href="../../xpressive/reference.html#header.boost.xpressive.regex_actions_hpp" title="Header <boost/xpressive/regex_actions.hpp>"> <link rel="prev" href="function.html" title="Struct template function"> @@ -26,42 +26,87 @@ <a name="boost.xpressive.value"></a><div class="titlepage"></div> <div class="refnamediv"> <h2><span class="refentrytitle">Struct template value</span></h2> -<p>boost::xpressive::value</p> +<p>boost::xpressive::value — <code class="computeroutput">value<></code> is a lazy wrapper for a value that can be used in xpressive semantic actions. </p> </div> <h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2> <div xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: <<a class="link" href="../../xpressive/reference.html#header.boost.xpressive.regex_actions_hpp" title="Header <boost/xpressive/regex_actions.hpp>">boost/xpressive/regex_actions.hpp</a>> </span><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> T<span class="special">></span> -<span class="keyword">struct</span> <a class="link" href="value.html" title="Struct template value">value</a> <span class="special">{</span> - <span class="comment">// types</span> - <span class="keyword">typedef</span> <span class="identifier">proto</span><span class="special">::</span><span class="identifier">extends</span><span class="special"><</span> <span class="keyword">typename</span> <span class="identifier">proto</span><span class="special">::</span><span class="identifier">terminal</span><span class="special"><</span> <span class="identifier">T</span> <span class="special">></span><span class="special">::</span><span class="identifier">type</span><span class="special">,</span> <a class="link" href="value.html" title="Struct template value">value</a><span class="special"><</span> <span class="identifier">T</span> <span class="special">></span> <span class="special">></span> <a name="boost.xpressive.value.base_type"></a><span class="identifier">base_type</span><span class="special">;</span> - +<span class="keyword">struct</span> <a class="link" href="value.html" title="Struct template value">value</a> <span class="special">:</span> + <span class="keyword">public</span> <span class="identifier">proto</span><span class="special">::</span><span class="identifier">extends</span><span class="special"><</span> <span class="identifier">proto</span><span class="special">::</span><span class="identifier">terminal</span><span class="special"><</span> <span class="identifier">T</span> <span class="special">></span><span class="special">::</span><span class="identifier">type</span><span class="special">,</span> <span class="identifier">value</span><span class="special"><</span> <span class="identifier">T</span> <span class="special">></span> <span class="special">></span> +<span class="special">{</span> <span class="comment">// <a class="link" href="value.html#boost.xpressive.valueconstruct-copy-destruct">construct/copy/destruct</a></span> - <a class="link" href="value.html#id1891341-bb"><span class="identifier">value</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> - <span class="keyword">explicit</span> <a class="link" href="value.html#id1891342-bb"><span class="identifier">value</span></a><span class="special">(</span><span class="identifier">T</span> <span class="keyword">const</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> + <a class="link" href="value.html#idp355237648-bb"><span class="identifier">value</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> + <span class="keyword">explicit</span> <a class="link" href="value.html#idp355238688-bb"><span class="identifier">value</span></a><span class="special">(</span><span class="identifier">T</span> <span class="keyword">const</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> - <span class="comment">// <a class="link" href="value.html#id1891322-bb">public member functions</a></span> - <span class="identifier">T</span> <span class="special">&</span> <a class="link" href="value.html#id1891326-bb"><span class="identifier">get</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> - <span class="identifier">T</span> <span class="keyword">const</span> <span class="special">&</span> <a class="link" href="value.html#id1891334-bb"><span class="identifier">get</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> + <span class="comment">// <a class="link" href="value.html#idp355234112-bb">public member functions</a></span> + <span class="identifier">T</span> <span class="special">&</span> <a class="link" href="value.html#idp355234672-bb"><span class="identifier">get</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> + <span class="identifier">T</span> <span class="keyword">const</span> <span class="special">&</span> <a class="link" href="value.html#idp355236064-bb"><span class="identifier">get</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> <span class="special">}</span><span class="special">;</span></pre></div> <div class="refsect1"> -<a name="id3890936"></a><h2>Description</h2> +<a name="idp533790656"></a><h2>Description</h2> +<p> +Below is an example that shows where <code class="computeroutput"><code class="computeroutput">value<></code></code> is useful.</p> +<pre class="programlisting"><span class="identifier">sregex</span> <span class="identifier">good_voodoo</span><span class="special">(</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">shared_ptr</span><span class="special"><</span><span class="keyword">int</span><span class="special">></span> <span class="identifier">pi</span><span class="special">)</span> +<span class="special">{</span> + <span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">xpressive</span><span class="special">;</span> + <span class="comment">// Use val() to hold the shared_ptr by value:</span> + <a class="link" href="basic_regex.html" title="Struct template basic_regex">sregex</a> <span class="identifier">rex</span> <span class="special">=</span> <span class="special">+</span><span class="special">(</span> <span class="identifier">_d</span> <span class="special">[</span> <span class="special">++</span><span class="special">*</span><span class="identifier">val</span><span class="special">(</span><span class="identifier">pi</span><span class="special">)</span> <span class="special">]</span> <span class="special">>></span> <span class="char">'!'</span> <span class="special">)</span><span class="special">;</span> + <span class="comment">// OK, rex holds a reference count to the integer.</span> + <span class="keyword">return</span> <span class="identifier">rex</span><span class="special">;</span> +<span class="special">}</span> +</pre> +<p> In the above code, <code class="computeroutput">xpressive::val()</code> is a function that returns a <code class="computeroutput">value<></code> object. Had <code class="computeroutput">val()</code> not been used here, the operation <code class="computeroutput">++*pi</code> would have been evaluated eagerly once, instead of lazily when the regex match happens. </p> +<div class="refsect2"> +<a name="idp533821856"></a><h3>Template Parameters</h3> +<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"> +<pre class="literallayout"><span class="keyword">typename</span> T</pre> +<p>The type of the value to store.</p> +</li></ol></div> +</div> <div class="refsect2"> -<a name="id3890940"></a><h3> +<a name="idp533824992"></a><h3> <a name="boost.xpressive.valueconstruct-copy-destruct"></a><code class="computeroutput">value</code> public construct/copy/destruct</h3> <div class="orderedlist"><ol class="orderedlist" type="1"> -<li class="listitem"><pre class="literallayout"><a name="id1891341-bb"></a><span class="identifier">value</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre></li> -<li class="listitem"><pre class="literallayout"><span class="keyword">explicit</span> <a name="id1891342-bb"></a><span class="identifier">value</span><span class="special">(</span><span class="identifier">T</span> <span class="keyword">const</span> <span class="special">&</span> t<span class="special">)</span><span class="special">;</span></pre></li> +<li class="listitem"> +<pre class="literallayout"><a name="idp355237648-bb"></a><span class="identifier">value</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre>Store a default-constructed <code class="computeroutput">T</code>. </li> +<li class="listitem"> +<pre class="literallayout"><span class="keyword">explicit</span> <a name="idp355238688-bb"></a><span class="identifier">value</span><span class="special">(</span><span class="identifier">T</span> <span class="keyword">const</span> <span class="special">&</span> t<span class="special">)</span><span class="special">;</span></pre>Store a copy of <code class="computeroutput">t</code>. <p> +</p> +<div class="variablelist"><table border="0" class="variablelist compact"> +<colgroup> +<col align="left" valign="top"> +<col> +</colgroup> +<tbody><tr> +<td><p><span class="term">Parameters:</span></p></td> +<td><div class="variablelist"><table border="0" class="variablelist compact"> +<colgroup> +<col align="left" valign="top"> +<col> +</colgroup> +<tbody><tr> +<td><p><span class="term"><code class="computeroutput">t</code></span></p></td> +<td><p>The initial value. </p></td> +</tr></tbody> +</table></div></td> +</tr></tbody> +</table></div> +</li> </ol></div> </div> <div class="refsect2"> -<a name="id3891040"></a><h3> -<a name="id1891322-bb"></a><code class="computeroutput">value</code> public member functions</h3> +<a name="idp533842032"></a><h3> +<a name="idp355234112-bb"></a><code class="computeroutput">value</code> public member functions</h3> <div class="orderedlist"><ol class="orderedlist" type="1"> -<li class="listitem"><pre class="literallayout"><span class="identifier">T</span> <span class="special">&</span> <a name="id1891326-bb"></a><span class="identifier">get</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre></li> -<li class="listitem"><pre class="literallayout"><span class="identifier">T</span> <span class="keyword">const</span> <span class="special">&</span> <a name="id1891334-bb"></a><span class="identifier">get</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre></li> +<li class="listitem"> +<pre class="literallayout"><span class="identifier">T</span> <span class="special">&</span> <a name="idp355234672-bb"></a><span class="identifier">get</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre> +<p>This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. </p> +</li> +<li class="listitem"> +<pre class="literallayout"><span class="identifier">T</span> <span class="keyword">const</span> <span class="special">&</span> <a name="idp355236064-bb"></a><span class="identifier">get</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre>Fetch the stored value. </li> </ol></div> </div> </div> |