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  27 <a name="core.ignore_unused"></a><a class="link" href="ignore_unused.html" title="ignore_unused">ignore_unused</a>
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  29 <div class="toc"><dl class="toc">
  30 <dt><span class="section"><a href="ignore_unused.html#core.ignore_unused.header_boost_core_ignore_unused_">Header
  31       &lt;boost/core/ignore_unused.hpp&gt;</a></span></dt>
  32 <dt><span class="section"><a href="ignore_unused.html#core.ignore_unused.acknowledgments">Acknowledgments</a></span></dt>
  33 </dl></div>
  34 <div class="simplesect">
  35 <div class="titlepage"><div><div><h3 class="title">
  36 <a name="idm46687075522192"></a>Authors</h3></div></div></div>
  37 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
  38           Adam Wulkiewicz
  39         </li></ul></div>
  40 </div>
  41 <div class="section">
  42 <div class="titlepage"><div><div><h3 class="title">
  43 <a name="core.ignore_unused.header_boost_core_ignore_unused_"></a><a class="link" href="ignore_unused.html#core.ignore_unused.header_boost_core_ignore_unused_" title="Header &lt;boost/core/ignore_unused.hpp&gt;">Header
  44       &lt;boost/core/ignore_unused.hpp&gt;</a>
  45 </h3></div></div></div>
  46 <p>
  47         The header <code class="computeroutput"><span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">core</span><span class="special">/</span><span class="identifier">ignore_unused</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>
  48         defines the function template <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">ignore_unused</span><span class="special">()</span></code>. It may be used to suppress the "unused
  49         variable" or "unused local typedefs" compiler warnings when
  50         the variable or typedef can't be removed or commented out, e.g. when some
  51         blocks of the code are conditionally activated. C++11 variadic templates
  52         are used if they're supported, otherwise they're emulated with overloads.
  53       </p>
  54 <div class="section">
  55 <div class="titlepage"><div><div><h4 class="title">
  56 <a name="core.ignore_unused.header_boost_core_ignore_unused_.usage"></a><a class="link" href="ignore_unused.html#core.ignore_unused.header_boost_core_ignore_unused_.usage" title="Usage">Usage</a>
  57 </h4></div></div></div>
  58 <pre class="programlisting"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">ignore_unused</span><span class="special">(</span><span class="identifier">v1</span><span class="special">,</span> <span class="identifier">v2</span><span class="special">,</span> <span class="identifier">v3</span><span class="special">);</span>
  59 <span class="identifier">boost</span><span class="special">::</span><span class="identifier">ignore_unused</span><span class="special">&lt;</span><span class="identifier">T1</span><span class="special">,</span> <span class="identifier">T2</span><span class="special">,</span> <span class="identifier">T3</span><span class="special">&gt;();</span>
  60 </pre>
  61 </div>
  62 <div class="section">
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  64 <a name="core.ignore_unused.header_boost_core_ignore_unused_.example"></a><a class="link" href="ignore_unused.html#core.ignore_unused.header_boost_core_ignore_unused_.example" title="Example">Example</a>
  65 </h4></div></div></div>
  66 <pre class="programlisting"><span class="keyword">int</span> <span class="identifier">fun</span><span class="special">(</span> <span class="keyword">int</span> <span class="identifier">foo</span><span class="special">,</span> <span class="keyword">int</span> <span class="identifier">bar</span> <span class="special">)</span>
  67 <span class="special">{</span>
  68     <span class="identifier">boost</span><span class="special">::</span><span class="identifier">ignore_unused</span><span class="special">(</span><span class="identifier">bar</span><span class="special">);</span>
  69 <span class="preprocessor">#ifdef</span> <span class="identifier">ENABLE_DEBUG_OUTPUT</span>
  70     <span class="keyword">if</span> <span class="special">(</span> <span class="identifier">foo</span> <span class="special">&lt;</span> <span class="identifier">bar</span> <span class="special">)</span>
  71         <span class="identifier">std</span><span class="special">::</span><span class="identifier">cerr</span> <span class="special">&lt;&lt;</span> <span class="string">"warning! foo &lt; bar"</span><span class="special">;</span>
  72 <span class="preprocessor">#endif</span>
  73     <span class="keyword">return</span> <span class="identifier">foo</span> <span class="special">+</span> <span class="number">2</span><span class="special">;</span>
  74 <span class="special">}</span>
  75 </pre>
  76 </div>
  77 </div>
  78 <div class="section">
  79 <div class="titlepage"><div><div><h3 class="title">
  80 <a name="core.ignore_unused.acknowledgments"></a><a class="link" href="ignore_unused.html#core.ignore_unused.acknowledgments" title="Acknowledgments">Acknowledgments</a>
  81 </h3></div></div></div>
  82 <p>
  83         <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">ignore_unused</span><span class="special">()</span></code>
  84         was contributed by Adam Wulkiewicz.
  85       </p>
  86 </div>
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  88 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
  89 <td align="left"></td>
  90 <td align="right"><div class="copyright-footer">Copyright &#169; 2014 Peter Dimov<br>Copyright &#169; 2014 Glen Fernandes<br>Copyright &#169; 2014 Andrey Semashev<p>
  91         Distributed under the <a href="http://boost.org/LICENSE_1_0.txt" target="_top">Boost
  92         Software License, Version 1.0</a>.
  93       </p>
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