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25</div> 26<div class="refentry"> 27<a name="boost.program_options.variable_value"></a><div class="titlepage"></div> 28<div class="refnamediv"> 29<h2><span class="refentrytitle">Class variable_value</span></h2> 30<p>boost::program_options::variable_value</p> 31</div> 32<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2> 33<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="../../program_options/reference.html#header.boost.program_options.variables_map_hpp" title="Header <boost/program_options/variables_map.hpp>">boost/program_options/variables_map.hpp</a>> 34 35</span> 36<span class="keyword">class</span> <a class="link" href="variable_value.html" title="Class variable_value">variable_value</a> <span class="special">{</span> 37<span class="keyword">public</span><span class="special">:</span> 38 <span class="comment">// <a class="link" href="variable_value.html#boost.program_options.variable_valueconstruct-copy-destruct">construct/copy/destruct</a></span> 39 <a class="link" href="variable_value.html#id-1_3_31_9_11_1_1_3_4-bb"><span class="identifier">variable_value</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> 40 <a class="link" href="variable_value.html#id-1_3_31_9_11_1_1_3_5-bb"><span class="identifier">variable_value</span></a><span class="special">(</span><span class="keyword">const</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">any</span> <span class="special">&</span><span class="special">,</span> <span class="keyword">bool</span><span class="special">)</span><span class="special">;</span> 41 42 <span class="comment">// <a class="link" href="variable_value.html#id-1_3_31_9_11_1_1_3_2-bb">friend functions</a></span> 43 <span class="keyword">friend</span> <span class="identifier">BOOST_PROGRAM_OPTIONS_DECL</span> <span class="keyword">void</span> 44 <a class="link" href="variable_value.html#id-1_3_31_9_11_1_1_3_2_1-bb"><span class="identifier">store</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="basic_parsed_options.html" title="Class template basic_parsed_options">basic_parsed_options</a><span class="special"><</span> <span class="keyword">char</span> <span class="special">></span> <span class="special">&</span><span class="special">,</span> <a class="link" href="variables_map.html" title="Class variables_map">variables_map</a> <span class="special">&</span><span class="special">,</span> <span class="keyword">bool</span><span class="special">)</span><span class="special">;</span> 45 46 <span class="comment">// <a class="link" href="variable_value.html#id-1_3_31_9_11_1_1_3_3-bb">public member functions</a></span> 47 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> T<span class="special">></span> <span class="keyword">const</span> <span class="identifier">T</span> <span class="special">&</span> <a class="link" href="variable_value.html#id-1_3_31_9_11_1_1_3_3_1-bb"><span class="identifier">as</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 48 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> T<span class="special">></span> <span class="identifier">T</span> <span class="special">&</span> <a class="link" href="variable_value.html#id-1_3_31_9_11_1_1_3_3_2-bb"><span class="identifier">as</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> 49 <span class="keyword">bool</span> <a class="link" href="variable_value.html#id-1_3_31_9_11_1_1_3_3_3-bb"><span class="identifier">empty</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 50 <span class="keyword">bool</span> <a class="link" href="variable_value.html#id-1_3_31_9_11_1_1_3_3_4-bb"><span class="identifier">defaulted</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 51 <span class="keyword">const</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">any</span> <span class="special">&</span> <a class="link" href="variable_value.html#id-1_3_31_9_11_1_1_3_3_5-bb"><span class="identifier">value</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 52 <span class="identifier">boost</span><span class="special">::</span><span class="identifier">any</span> <span class="special">&</span> <a class="link" href="variable_value.html#id-1_3_31_9_11_1_1_3_3_6-bb"><span class="identifier">value</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> 53<span class="special">}</span><span class="special">;</span></pre></div> 54<div class="refsect1"> 55<a name="id-1.3.31.9.12.5.4"></a><h2>Description</h2> 56<p>Class holding value of option. Contains details about how the value is set and allows to conveniently obtain the value. </p> 57<div class="refsect2"> 58<a name="id-1.3.31.9.12.5.4.3"></a><h3> 59<a name="boost.program_options.variable_valueconstruct-copy-destruct"></a><code class="computeroutput">variable_value</code> 60 public 61 construct/copy/destruct</h3> 62<div class="orderedlist"><ol class="orderedlist" type="1"> 63<li class="listitem"><pre class="literallayout"><a name="id-1_3_31_9_11_1_1_3_4-bb"></a><span class="identifier">variable_value</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre></li> 64<li class="listitem"><pre class="literallayout"><a name="id-1_3_31_9_11_1_1_3_5-bb"></a><span class="identifier">variable_value</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">any</span> <span class="special">&</span> xv<span class="special">,</span> <span class="keyword">bool</span> xdefaulted<span class="special">)</span><span class="special">;</span></pre></li> 65</ol></div> 66</div> 67<div class="refsect2"> 68<a name="id-1.3.31.9.12.5.4.4"></a><h3> 69<a name="id-1_3_31_9_11_1_1_3_2-bb"></a><code class="computeroutput">variable_value</code> friend functions</h3> 70<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"> 71<pre class="literallayout"><span class="keyword">friend</span> <span class="identifier">BOOST_PROGRAM_OPTIONS_DECL</span> <span class="keyword">void</span> 72<a name="id-1_3_31_9_11_1_1_3_2_1-bb"></a><span class="identifier">store</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="basic_parsed_options.html" title="Class template basic_parsed_options">basic_parsed_options</a><span class="special"><</span> <span class="keyword">char</span> <span class="special">></span> <span class="special">&</span> options<span class="special">,</span> <a class="link" href="variables_map.html" title="Class variables_map">variables_map</a> <span class="special">&</span> m<span class="special">,</span> <span class="keyword">bool</span><span class="special">)</span><span class="special">;</span></pre> 73<p>Stores in 'm' all options that are defined in 'options'. If 'm' already has a non-defaulted value of an option, that value is not changed, even if 'options' specify some value. </p> 74</li></ol></div> 75</div> 76<div class="refsect2"> 77<a name="id-1.3.31.9.12.5.4.5"></a><h3> 78<a name="id-1_3_31_9_11_1_1_3_3-bb"></a><code class="computeroutput">variable_value</code> public member functions</h3> 79<div class="orderedlist"><ol class="orderedlist" type="1"> 80<li class="listitem"> 81<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> T<span class="special">></span> <span class="keyword">const</span> <span class="identifier">T</span> <span class="special">&</span> <a name="id-1_3_31_9_11_1_1_3_3_1-bb"></a><span class="identifier">as</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 82<p>If stored value if of type T, returns that value. Otherwise, throws boost::bad_any_cast exception. </p> 83</li> 84<li class="listitem"> 85<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> T<span class="special">></span> <span class="identifier">T</span> <span class="special">&</span> <a name="id-1_3_31_9_11_1_1_3_3_2-bb"></a><span class="identifier">as</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre> 86<p>This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. </p> 87</li> 88<li class="listitem"> 89<pre class="literallayout"><span class="keyword">bool</span> <a name="id-1_3_31_9_11_1_1_3_3_3-bb"></a><span class="identifier">empty</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre>Returns true if no value is stored. </li> 90<li class="listitem"> 91<pre class="literallayout"><span class="keyword">bool</span> <a name="id-1_3_31_9_11_1_1_3_3_4-bb"></a><span class="identifier">defaulted</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 92<p>Returns true if the value was not explicitly given, but has default value. </p> 93</li> 94<li class="listitem"> 95<pre class="literallayout"><span class="keyword">const</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">any</span> <span class="special">&</span> <a name="id-1_3_31_9_11_1_1_3_3_5-bb"></a><span class="identifier">value</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 96<p>Returns the contained value. </p> 97</li> 98<li class="listitem"> 99<pre class="literallayout"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">any</span> <span class="special">&</span> <a name="id-1_3_31_9_11_1_1_3_3_6-bb"></a><span class="identifier">value</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre> 100<p>Returns the contained value. </p> 101</li> 102</ol></div> 103</div> 104</div> 105</div> 106<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 107<td align="left"></td> 108<td align="right"><div class="copyright-footer">Copyright © 2002-2004 Vladimir Prus<p>Distributed under the Boost Software License, Version 1.0. 109 (See accompanying file <code class="filename">LICENSE_1_0.txt</code> or copy at 110 <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) 111 </p> 112</div></td> 113</tr></table> 114<hr> 115<div class="spirit-nav"> 116<a accesskey="p" href="basic_parsed_options.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../program_options/reference.html#header.boost.program_options.variables_map_hpp"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="variables_map.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> 117</div> 118</body> 119</html> 120
