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<h1>Copy Constructible</h1>
<h3>Description</h3>
<p>A type is Copy Constructible if it is possible to copy objects of that
type.</p>
<h3>Notation</h3>
<table summary="">
<tr>
<td valign="top"><tt>T</tt></td>
<td valign="top">is type that is a model of Copy Constructible</td>
</tr>
<tr>
<td valign="top"><tt>t</tt></td>
<td valign="top">is an object of type <tt>T</tt></td>
</tr>
<tr>
<td valign="top"><tt>u</tt></td>
<td valign="top">is an object of type <tt>const T</tt></td>
</tr>
</table>
<h3>Definitions</h3>
<h3>Valid expressions</h3>
<table border summary="">
<tr>
<th>Name</th>
<th>Expression</th>
<th>Return type</th>
<th>Semantics</th>
</tr>
<tr>
<td valign="top">Copy constructor</td>
<td valign="top"><tt>T(t)</tt></td>
<td valign="top"><tt>T</tt></td>
<td valign="top"><tt>t</tt> is equivalent to <tt>T(t)</tt></td>
</tr>
<tr>
<td valign="top">Copy constructor</td>
<td valign="top">
<pre>
T(u)
</pre>
</td>
<td valign="top"><tt>T</tt></td>
<td valign="top"><tt>u</tt> is equivalent to <tt>T(u)</tt></td>
</tr>
<tr>
<td valign="top">Destructor</td>
<td valign="top">
<pre>
t.~T()
</pre>
</td>
<td valign="top"><tt>T</tt></td>
<td valign="top"> </td>
</tr>
<tr>
<td valign="top">Address Operator</td>
<td valign="top">
<pre>
&t
</pre>
</td>
<td valign="top"><tt>T*</tt></td>
<td valign="top">denotes the address of <tt>t</tt></td>
</tr>
<tr>
<td valign="top">Address Operator</td>
<td valign="top">
<pre>
&u
</pre>
</td>
<td valign="top"><tt>T*</tt></td>
<td valign="top">denotes the address of <tt>u</tt></td>
</tr>
</table>
<h3>Models</h3>
<ul>
<li><tt>int</tt></li>
<li><tt>std::pair</tt></li>
</ul>
<h3>Concept Checking Class</h3>
<pre>
template <class T>
struct CopyConstructibleConcept
{
void constraints() {
T a(b); // require copy constructor
T* ptr = &a; // require address of operator
const_constraints(a);
ignore_unused_variable_warning(ptr);
}
void const_constraints(const T& a) {
T c(a); // require const copy constructor
const T* ptr = &a; // require const address of operator
ignore_unused_variable_warning(c);
ignore_unused_variable_warning(ptr);
}
T b;
};
</pre>
<h3>See also</h3>
<p><a href="http://www.sgi.com/tech/stl/DefaultConstructible.html">Default
Constructible</a> and <a href="./Assignable.html">Assignable</a><br></p>
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<p>Revised
<!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %B, %Y" startspan -->05
December, 2006<!--webbot bot="Timestamp" endspan i-checksum="38516" --></p>
<table summary="">
<tr valign="top">
<td nowrap><i>Copyright © 2000</i></td>
<td><i><a href="http://www.lsc.nd.edu/~jsiek">Jeremy Siek</a>, Univ.of
Notre Dame (<a href=
"mailto:jsiek@lsc.nd.edu">jsiek@lsc.nd.edu</a>)</i></td>
</tr>
</table>
<p><i>Distributed under the Boost Software License, Version 1.0. (See
accompanying file <a href="../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
copy at <a href=
"http://www.boost.org/LICENSE_1_0.txt">http://www.boost.org/LICENSE_1_0.txt</a>)</i></p>
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