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boost/core/null_deleter.hpp

/*
 *          Copyright Andrey Semashev 2007 - 2014.
 * 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)
 */
/*!
 * \file   null_deleter.hpp
 * \author Andrey Semashev
 * \date   22.04.2007
 *
 * This header contains a \c null_deleter implementation. This is an empty
 * function object that receives a pointer and does nothing with it.
 * Such empty deletion strategy may be convenient, for example, when
 * constructing <tt>shared_ptr</tt>s that point to some object that should not be
 * deleted (i.e. a variable on the stack or some global singleton, like <tt>std::cout</tt>).
 */

#ifndef BOOST_CORE_NULL_DELETER_HPP
#define BOOST_CORE_NULL_DELETER_HPP

#include <boost/config.hpp>

#ifdef BOOST_HAS_PRAGMA_ONCE
#pragma once
#endif

namespace boost {

// Block unintended ADL
namespace null_deleter_ns {

//! A function object that does nothing and can be used as an empty deleter for \c shared_ptr
struct null_deleter
{
    //! Function object result type
    typedef void result_type;
    /*!
     * Does nothing
     */
    template< typename T >
    void operator() (T*) const BOOST_NOEXCEPT {}
};

} // namespace null_deleter_ns

using null_deleter_ns::null_deleter;

} // namespace boost

#endif // BOOST_CORE_NULL_DELETER_HPP