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| <a name="boost.log.fallback_to_default"></a><div class="titlepage"></div> |
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| <h2><span class="refentrytitle">Struct template fallback_to_default</span></h2> |
| <p>boost::log::fallback_to_default</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: <<a class="link" href="../../attributes.html#header.boost.log.attributes.fallback_policy_fwd_hpp" title="Header <boost/log/attributes/fallback_policy_fwd.hpp>">boost/log/attributes/fallback_policy_fwd.hpp</a>> |
| |
| </span><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> DefaultT<span class="special">></span> |
| <span class="keyword">struct</span> <a class="link" href="fallback_to_default.html" title="Struct template fallback_to_default">fallback_to_default</a> <span class="special">{</span> |
| <span class="comment">// <a class="link" href="fallback_to_default.html#boost.log.fallback_to_defaultconstruct-copy-destruct">construct/copy/destruct</a></span> |
| <a class="link" href="fallback_to_default.html#idp42062848-bb"><span class="identifier">fallback_to_default</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> |
| <span class="keyword">explicit</span> <a class="link" href="fallback_to_default.html#idp42063552-bb"><span class="identifier">fallback_to_default</span></a><span class="special">(</span><span class="identifier">default_type</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="fallback_to_default.html#idp42055856-bb">public member functions</a></span> |
| <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> FunT<span class="special">></span> <span class="keyword">bool</span> <a class="link" href="fallback_to_default.html#idp42056416-bb"><span class="identifier">apply_default</span></a><span class="special">(</span><span class="identifier">FunT</span> <span class="special">&</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> |
| <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> FunT<span class="special">></span> <span class="keyword">bool</span> <a class="link" href="fallback_to_default.html#idp42059552-bb"><span class="identifier">apply_default</span></a><span class="special">(</span><span class="identifier">FunT</span> <span class="keyword">const</span> <span class="special">&</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> |
| |
| <span class="comment">// <a class="link" href="fallback_to_default.html#idp42065232-bb">public static functions</a></span> |
| <span class="keyword">static</span> <span class="keyword">void</span> <a class="link" href="fallback_to_default.html#idp42065792-bb"><span class="identifier">on_invalid_type</span></a><span class="special">(</span><span class="identifier">type_info_wrapper</span> <span class="keyword">const</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> |
| <span class="keyword">static</span> <span class="keyword">void</span> <a class="link" href="fallback_to_default.html#idp42068128-bb"><span class="identifier">on_missing_value</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> |
| <span class="special">}</span><span class="special">;</span></pre></div> |
| <div class="refsect1"> |
| <a name="idp107469664"></a><h2>Description</h2> |
| <p>The <code class="computeroutput"><a class="link" href="fallback_to_default.html" title="Struct template fallback_to_default">fallback_to_default</a></code> policy results in a default value if the attribute value cannot be extracted. </p> |
| <div class="refsect2"> |
| <a name="idp107471648"></a><h3> |
| <a name="boost.log.fallback_to_defaultconstruct-copy-destruct"></a><code class="computeroutput">fallback_to_default</code> |
| public |
| construct/copy/destruct</h3> |
| <div class="orderedlist"><ol class="orderedlist" type="1"> |
| <li class="listitem"> |
| <pre class="literallayout"><a name="idp42062848-bb"></a><span class="identifier">fallback_to_default</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre> |
| <p>Default constructor. </p> |
| </li> |
| <li class="listitem"> |
| <pre class="literallayout"><span class="keyword">explicit</span> <a name="idp42063552-bb"></a><span class="identifier">fallback_to_default</span><span class="special">(</span><span class="identifier">default_type</span> <span class="keyword">const</span> <span class="special">&</span> def_val<span class="special">)</span><span class="special">;</span></pre> |
| <p>Initializing constructor. </p> |
| </li> |
| </ol></div> |
| </div> |
| <div class="refsect2"> |
| <a name="idp107484544"></a><h3> |
| <a name="idp42055856-bb"></a><code class="computeroutput">fallback_to_default</code> public member functions</h3> |
| <div class="orderedlist"><ol class="orderedlist" type="1"> |
| <li class="listitem"> |
| <pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> FunT<span class="special">></span> <span class="keyword">bool</span> <a name="idp42056416-bb"></a><span class="identifier">apply_default</span><span class="special">(</span><span class="identifier">FunT</span> <span class="special">&</span> fun<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> |
| <p>The method is called in order to apply a function object to the default value. </p> |
| </li> |
| <li class="listitem"> |
| <pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> FunT<span class="special">></span> <span class="keyword">bool</span> <a name="idp42059552-bb"></a><span class="identifier">apply_default</span><span class="special">(</span><span class="identifier">FunT</span> <span class="keyword">const</span> <span class="special">&</span> fun<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> |
| <p>The method is called in order to apply a function object to the default value. </p> |
| </li> |
| </ol></div> |
| </div> |
| <div class="refsect2"> |
| <a name="idp107506048"></a><h3> |
| <a name="idp42065232-bb"></a><code class="computeroutput">fallback_to_default</code> public static functions</h3> |
| <div class="orderedlist"><ol class="orderedlist" type="1"> |
| <li class="listitem"> |
| <pre class="literallayout"><span class="keyword">static</span> <span class="keyword">void</span> <a name="idp42065792-bb"></a><span class="identifier">on_invalid_type</span><span class="special">(</span><span class="identifier">type_info_wrapper</span> <span class="keyword">const</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span></pre> |
| <p>The method is called when value extraction failed because the attribute value has different type than requested. </p> |
| </li> |
| <li class="listitem"> |
| <pre class="literallayout"><span class="keyword">static</span> <span class="keyword">void</span> <a name="idp42068128-bb"></a><span class="identifier">on_missing_value</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre> |
| <p>The method is called when value extraction failed because the attribute value was not found. </p> |
| </li> |
| </ol></div> |
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| </div> |
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| <td align="right"><div class="copyright-footer">Copyright © 2007-2015 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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