1 /*
2  *          Copyright Andrey Semashev 2007 - 2014.
3  * Distributed under the Boost Software License, Version 1.0.
4  *    (See accompanying file LICENSE_1_0.txt or copy at
5  *          http://www.boost.org/LICENSE_1_0.txt)
6  */
7 /*!
8  * \file   null_deleter.hpp
9  * \author Andrey Semashev
10  * \date   22.04.2007
11  *
12  * This header contains a \c null_deleter implementation. This is an empty
13  * function object that receives a pointer and does nothing with it.
14  * Such empty deletion strategy may be convenient, for example, when
15  * constructing <tt>shared_ptr</tt>s that point to some object that should not be
16  * deleted (i.e. a variable on the stack or some global singleton, like <tt>std::cout</tt>).
17  */
18 
19 #ifndef BOOST_CORE_NULL_DELETER_HPP
20 #define BOOST_CORE_NULL_DELETER_HPP
21 
22 #include <boost/config.hpp>
23 
24 #ifdef BOOST_HAS_PRAGMA_ONCE
25 #pragma once
26 #endif
27 
28 namespace boost {
29 
30 //! A function object that does nothing and can be used as an empty deleter for \c shared_ptr
31 struct null_deleter
32 {
33     //! Function object result type
34     typedef void result_type;
35     /*!
36      * Does nothing
37      */
38     template< typename T >
operator ()boost::null_deleter39     void operator() (T*) const BOOST_NOEXCEPT {}
40 };
41 
42 } // namespace boost
43 
44 #endif // BOOST_CORE_NULL_DELETER_HPP
45