boost/core/null_deleter.hpp

0001 /*
0002  *          Copyright Andrey Semashev 2007 - 2014.
0003  * Distributed under the Boost Software License, Version 1.0.
0004  *    (See accompanying file LICENSE_1_0.txt or copy at
0005  *          http://www.boost.org/LICENSE_1_0.txt)
0006  */
0007 /*!
0008  * \file   null_deleter.hpp
0009  * \author Andrey Semashev
0010  * \date   22.04.2007
0011  *
0012  * This header contains a \c null_deleter implementation. This is an empty
0013  * function object that receives a pointer and does nothing with it.
0014  * Such empty deletion strategy may be convenient, for example, when
0015  * constructing <tt>shared_ptr</tt>s that point to some object that should not be
0016  * deleted (i.e. a variable on the stack or some global singleton, like <tt>std::cout</tt>).
0017  */
0018
0019 #ifndef BOOST_CORE_NULL_DELETER_HPP
0020 #define BOOST_CORE_NULL_DELETER_HPP
0021
0022 #include <boost/config.hpp>
0023
0024 #ifdef BOOST_HAS_PRAGMA_ONCE
0025 #pragma once
0026 #endif
0027
0028 namespace boost {
0029
0030 //! A function object that does nothing and can be used as an empty deleter for \c shared_ptr
0031 struct null_deleter
0032 {
0033     //! Function object result type
0034     typedef void result_type;
0035     /*!
0036      * Does nothing
0037      */
0038     template< typename T >
0039     void operator() (T*) const BOOST_NOEXCEPT {}
0040 };
0041
0042 } // namespace boost
0043
0044 #endif // BOOST_CORE_NULL_DELETER_HPP