12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879808182 |
- <!doctype HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
- <html>
- <!--
- (C) Copyright 2002-4 Robert Ramey - http://www.rrsd.com .
- Use, modification and distribution is subject to the Boost Software
- License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
- http://www.boost.org/LICENSE_1_0.txt)
- -->
- <head>
- <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
- <link rel="stylesheet" type="text/css" href="../../../boost.css">
- <link rel="stylesheet" type="text/css" href="style.css">
- <title>Serialization - <code style="white-space: normal">state_saver</code></title>
- </head>
- <body link="#0000ff" vlink="#800080">
- <table border="0" cellpadding="7" cellspacing="0" width="100%" summary="header">
- <tr>
- <td valign="top" width="300">
- <h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../boost.png" border="0"></a></h3>
- </td>
- <td valign="top">
- <h1 align="center">Serialization</h1>
- <h2 align="center"><code style="white-space: normal">state_saver</code</h2>
- </td>
- </tr>
- </table>
- <hr>
- <p>
- Sometimes a certain value has to change only for a limited scope.
- This class wrapper saves a copy of the current state of some object,
- and resets the object's state at destruction time, undoing any change the object
- may have gone through. Here is the interface:
- <pre><code>
- template<class T>
- // T requirements:
- // - POD or object semantic (cannot be reference, function, ...)
- // - copy constructor
- // - operator = (no-throw one preferred)
- class state_saver : private boost::noncopyable
- {
- private:
- ... // implementation
- public:
- state_saver(T & object);
- ~state_saver();
- };
- </code></pre>
- The complete implementation can be found
- <a target="state_saver" href="../../../boost/serialization/state_saver.hpp">here</a>
- The following illustrates how this is expected to be used.
- <pre><code>
- #include <boost/state_saver.hpp>
- void func(A & a)
- boost::state_saver<A> s(a);
- ... // alter state of a by calling non-const functions
- ... // call other functions
- // original state of a automatically restored on exit
- }
- </pre></code>
- <h3>History</h3>
- This is a generalization of Daryle Walker's
- <a href="../../../libs/io/doc/ios_state.html">io_state_saver</a> library.
- <p>
- Robert Ramey made an initial version for the serialization library.
- <p>
- Pavel Vozenilek made several non-obvious refinements to make it more
- secure and boost friendly
- <hr>
- <p><i>© Copyright <a href="http://www.rrsd.com">Robert Ramey</a> 2002-2004.
- Distributed under the Boost Software License, Version 1.0. (See
- accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
- </i></p>
- </body>
- </html>
|