1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Class template has_attribute</title> 5<link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="../../../index.html" title="Chapter 1. Boost.Log v2"> 8<link rel="up" href="../../../expressions.html#header.boost.log.expressions.predicates.has_attr_hpp" title="Header <boost/log/expressions/predicates/has_attr.hpp>"> 9<link rel="prev" href="ends_wit_idm46079577858224.html" title="Function template ends_with"> 10<link rel="next" href="has_attr_idm46079577837584.html" title="Class has_attribute<void>"> 11</head> 12<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 13<table cellpadding="2" width="100%"><tr><td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../../boost.png"></td></tr></table> 14<hr> 15<div class="spirit-nav"> 16<a accesskey="p" href="ends_wit_idm46079577858224.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../expressions.html#header.boost.log.expressions.predicates.has_attr_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="has_attr_idm46079577837584.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a> 17</div> 18<div class="refentry"> 19<a name="boost.log.expressions.has_attribute"></a><div class="titlepage"></div> 20<div class="refnamediv"> 21<h2><span class="refentrytitle">Class template has_attribute</span></h2> 22<p>boost::log::expressions::has_attribute</p> 23</div> 24<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2> 25<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="../../../expressions.html#header.boost.log.expressions.predicates.has_attr_hpp" title="Header <boost/log/expressions/predicates/has_attr.hpp>">boost/log/expressions/predicates/has_attr.hpp</a>> 26 27</span><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> T<span class="special">></span> 28<span class="keyword">class</span> <a class="link" href="has_attribute.html" title="Class template has_attribute">has_attribute</a> <span class="special">{</span> 29<span class="keyword">public</span><span class="special">:</span> 30 <span class="comment">// types</span> 31 <span class="keyword">typedef</span> <span class="keyword">bool</span> <a name="boost.log.expressions.has_attribute.result_type"></a><span class="identifier">result_type</span><span class="special">;</span> <span class="comment">// Function result_type. </span> 32 <span class="keyword">typedef</span> <span class="identifier">T</span> <a name="boost.log.expressions.has_attribute.value_type"></a><span class="identifier">value_type</span><span class="special">;</span> <span class="comment">// Expected attribute value type. </span> 33 34 <span class="comment">// <a class="link" href="has_attribute.html#boost.log.expressions.has_attributeconstruct-copy-destruct">construct/copy/destruct</a></span> 35 <span class="keyword">explicit</span> <a class="link" href="has_attribute.html#idm46079577839968-bb"><span class="identifier">has_attribute</span></a><span class="special">(</span><span class="identifier">attribute_name</span> <span class="keyword">const</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 36 37 <span class="comment">// <a class="link" href="has_attribute.html#idm46079577845856-bb">public member functions</a></span> 38 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> ArgT<span class="special">></span> <span class="identifier">result_type</span> <a class="link" href="has_attribute.html#idm46079577845296-bb"><span class="keyword">operator</span><span class="special">(</span><span class="special">)</span></a><span class="special">(</span><span class="identifier">ArgT</span> <span class="keyword">const</span> <span class="special">&</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 39<span class="special">}</span><span class="special">;</span></pre></div> 40<div class="refsect1"> 41<a name="idm44984871664576"></a><h2>Description</h2> 42<p>An attribute value presence checker. </p> 43<div class="refsect2"> 44<a name="idm44984871663856"></a><h3> 45<a name="boost.log.expressions.has_attributeconstruct-copy-destruct"></a><code class="computeroutput">has_attribute</code> 46 public 47 construct/copy/destruct</h3> 48<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"> 49<pre class="literallayout"><span class="keyword">explicit</span> <a name="idm46079577839968-bb"></a><span class="identifier">has_attribute</span><span class="special">(</span><span class="identifier">attribute_name</span> <span class="keyword">const</span> <span class="special">&</span> name<span class="special">)</span><span class="special">;</span></pre> 50<p>Initializing constructor</p> 51<p> 52</p> 53<div class="variablelist"><table border="0" class="variablelist compact"> 54<colgroup> 55<col align="left" valign="top"> 56<col> 57</colgroup> 58<tbody><tr> 59<td><p><span class="term">Parameters:</span></p></td> 60<td><div class="variablelist"><table border="0" class="variablelist compact"> 61<colgroup> 62<col align="left" valign="top"> 63<col> 64</colgroup> 65<tbody><tr> 66<td><p><span class="term"><code class="computeroutput">name</code></span></p></td> 67<td><p>Attribute name </p></td> 68</tr></tbody> 69</table></div></td> 70</tr></tbody> 71</table></div> 72</li></ol></div> 73</div> 74<div class="refsect2"> 75<a name="idm44984871651728"></a><h3> 76<a name="idm46079577845856-bb"></a><code class="computeroutput">has_attribute</code> public member functions</h3> 77<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"> 78<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> ArgT<span class="special">></span> <span class="identifier">result_type</span> <a name="idm46079577845296-bb"></a><span class="keyword">operator</span><span class="special">(</span><span class="special">)</span><span class="special">(</span><span class="identifier">ArgT</span> <span class="keyword">const</span> <span class="special">&</span> arg<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 79<p>Checking operator</p> 80<p> 81 82</p> 83<div class="variablelist"><table border="0" class="variablelist compact"> 84<colgroup> 85<col align="left" valign="top"> 86<col> 87</colgroup> 88<tbody> 89<tr> 90<td><p><span class="term">Parameters:</span></p></td> 91<td><div class="variablelist"><table border="0" class="variablelist compact"> 92<colgroup> 93<col align="left" valign="top"> 94<col> 95</colgroup> 96<tbody><tr> 97<td><p><span class="term"><code class="computeroutput">arg</code></span></p></td> 98<td><p>A set of attribute values or a log record </p></td> 99</tr></tbody> 100</table></div></td> 101</tr> 102<tr> 103<td><p><span class="term">Returns:</span></p></td> 104<td><p><code class="computeroutput">true</code> if the log record contains the sought attribute value, <code class="computeroutput">false</code> otherwise </p></td> 105</tr> 106</tbody> 107</table></div> 108</li></ol></div> 109</div> 110<div class="refsect2"> 111<a name="idm44984871633312"></a><h3>Specializations</h3> 112<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p><a class="link" href="has_attr_idm46079577837584.html" title="Class has_attribute<void>">Class has_attribute<void></a></p></li></ul></div> 113</div> 114</div> 115</div> 116<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 117<td align="left"></td> 118<td align="right"><div class="copyright-footer">Copyright © 2007-2019 Andrey Semashev<p> 119 Distributed under the Boost Software License, Version 1.0. (See accompanying 120 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>). 121 </p> 122</div></td> 123</tr></table> 124<hr> 125<div class="spirit-nav"> 126<a accesskey="p" href="ends_wit_idm46079577858224.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../expressions.html#header.boost.log.expressions.predicates.has_attr_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="has_attr_idm46079577837584.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a> 127</div> 128</body> 129</html> 130
