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<h2><span class="refentrytitle">Function template if_</span></h2>
<p>boost::log::expressions::if_</p>
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<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: &lt;<a class="link" href="../../../expressions.html#header.boost.log.expressions.formatters.if_hpp" title="Header &lt;boost/log/expressions/formatters/if.hpp&gt;">boost/log/expressions/formatters/if.hpp</a>&gt;

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<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> CondT<span class="special">&gt;</span> <span class="emphasis"><em><span class="identifier">unspecified</span></em></span> <span class="identifier">if_</span><span class="special">(</span><span class="identifier">CondT</span> <span class="keyword">const</span> <span class="special">&amp;</span> cond<span class="special">)</span><span class="special">;</span></pre></div>
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<a name="idp96941552"></a><h2>Description</h2>
<p>The function returns a conditional formatter generator object. The generator provides <code class="computeroutput">operator[]</code> that can be used to construct the actual formatter. The formatter must participate in a streaming expression.</p>
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<td><p><span class="term"><code class="computeroutput">cond</code></span></p></td>
<td><p>A filter expression that will be used as the condition </p></td>
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<td align="right"><div class="copyright-footer">Copyright &#169; 2007-2014 Andrey Semashev<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>).
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