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26<div class="titlepage"><div><div><h3 class="title">
27<a name="boost_typetraits.reference.is_object"></a><a class="link" href="is_object.html" title="is_object">is_object</a>
28</h3></div></div></div>
29<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span>
30<span class="keyword">struct</span> <span class="identifier">is_object</span> <span class="special">:</span> <span class="keyword">public</span> <em class="replaceable"><code><a class="link" href="integral_constant.html" title="integral_constant">true_type</a>-or-<a class="link" href="integral_constant.html" title="integral_constant">false_type</a></code></em> <span class="special">{};</span>
31</pre>
32<p>
33 <span class="bold"><strong>Inherits:</strong></span> If T is a (possibly cv-qualified)
34 object type then inherits from <a class="link" href="integral_constant.html" title="integral_constant">true_type</a>,
35 otherwise inherits from <a class="link" href="integral_constant.html" title="integral_constant">false_type</a>.
36 All types are object types except references, void, and function types.
37 </p>
38<p>
39 <span class="bold"><strong>C++ Standard Reference:</strong></span> 3.9p9.
40 </p>
41<p>
42 <span class="bold"><strong>Compiler Compatibility:</strong></span> All current compilers
43 are supported by this trait.
44 </p>
45<p>
46 <span class="bold"><strong>Header:</strong></span> <code class="computeroutput"> <span class="preprocessor">#include</span>
47 <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">type_traits</span><span class="special">/</span><span class="identifier">is_object</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>
48 or <code class="computeroutput"> <span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">type_traits</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>
49 </p>
50<p>
51 <span class="bold"><strong>Examples:</strong></span>
52 </p>
53<div class="blockquote"><blockquote class="blockquote"><p>
54 <code class="computeroutput"><span class="identifier">is_object</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&gt;</span></code>
55 inherits from <code class="computeroutput"><a class="link" href="integral_constant.html" title="integral_constant">true_type</a></code>.
56 </p></blockquote></div>
57<div class="blockquote"><blockquote class="blockquote"><p>
58 <code class="computeroutput"><span class="identifier">is_object</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">*&gt;::</span><span class="identifier">type</span></code> is the type <code class="computeroutput"><a class="link" href="integral_constant.html" title="integral_constant">true_type</a></code>.
59 </p></blockquote></div>
60<div class="blockquote"><blockquote class="blockquote"><p>
61 <code class="computeroutput"><span class="identifier">is_object</span><span class="special">&lt;</span><span class="keyword">int</span> <span class="special">(*)(</span><span class="keyword">void</span><span class="special">)&gt;::</span><span class="identifier">value</span></code> is an integral constant expression
62 that evaluates to <span class="emphasis"><em>true</em></span>.
63 </p></blockquote></div>
64<div class="blockquote"><blockquote class="blockquote"><p>
65 <code class="computeroutput"><span class="identifier">is_object</span><span class="special">&lt;</span><span class="keyword">int</span> <span class="special">(</span><span class="identifier">MyClass</span><span class="special">::*)(</span><span class="keyword">void</span><span class="special">)</span><span class="keyword">const</span><span class="special">&gt;::</span><span class="identifier">value</span></code> is an integral constant expression
66 that evaluates to <span class="emphasis"><em>true</em></span>.
67 </p></blockquote></div>
68<div class="blockquote"><blockquote class="blockquote"><p>
69 <code class="computeroutput"><span class="identifier">is_object</span><span class="special">&lt;</span><span class="keyword">int</span> <span class="special">&amp;&gt;::</span><span class="identifier">value</span></code> is an integral constant expression
70 that evaluates to <span class="emphasis"><em>false</em></span>: reference types are not objects
71 </p></blockquote></div>
72<div class="blockquote"><blockquote class="blockquote"><p>
73 <code class="computeroutput"><span class="identifier">is_object</span><span class="special">&lt;</span><span class="keyword">int</span> <span class="special">(</span><span class="keyword">double</span><span class="special">)&gt;::</span><span class="identifier">value</span></code>
74 is an integral constant expression that evaluates to <span class="emphasis"><em>false</em></span>:
75 function types are not objects
76 </p></blockquote></div>
77<div class="blockquote"><blockquote class="blockquote"><p>
78 <code class="computeroutput"><span class="identifier">is_object</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="keyword">void</span><span class="special">&gt;::</span><span class="identifier">value</span></code>
79 is an integral constant expression that evaluates to <span class="emphasis"><em>false</em></span>:
80 void is not an object type
81 </p></blockquote></div>
82<div class="blockquote"><blockquote class="blockquote"><p>
83 <code class="computeroutput"><span class="identifier">is_object</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;::</span><span class="identifier">value_type</span></code> is the type <code class="computeroutput"><span class="keyword">bool</span></code>.
84 </p></blockquote></div>
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