boost/utility/in_place_factory.hpp

// Copyright (C) 2003, Fernando Luis Cacciola Carballal.
//
// 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)
//
// See http://www.boost.org/lib/optional for documentation.
//
// You are welcome to contact the author at:
//  fernando_cacciola@hotmail.com
//
#ifndef BOOST_UTILITY_INPLACE_FACTORY_25AGO2003_HPP
#define BOOST_UTILITY_INPLACE_FACTORY_25AGO2003_HPP

#include <boost/utility/detail/in_place_factory_prefix.hpp>

#include <boost/type.hpp>

namespace boost {

class in_place_factory_base {} ;

#define BOOST_DEFINE_INPLACE_FACTORY_CLASS(z,n,_) \
template< BOOST_PP_ENUM_PARAMS(BOOST_PP_INC(n),class A) > \
class BOOST_PP_CAT(in_place_factory, BOOST_PP_INC(n) ) : public in_place_factory_base \
{ \
public: \
\
  BOOST_PP_CAT(in_place_factory, BOOST_PP_INC(n) ) ( BOOST_PP_ENUM_BINARY_PARAMS(BOOST_PP_INC(n),A,const& a) ) \
    : \
    BOOST_PP_ENUM( BOOST_PP_INC(n), BOOST_DEFINE_INPLACE_FACTORY_CLASS_MEMBER_INIT, _ ) \
  {} \
\
  template<class T> \
  void apply ( void* address BOOST_APPEND_EXPLICIT_TEMPLATE_TYPE(T) ) const \
  { \
    new ( address ) T ( BOOST_PP_ENUM_PARAMS( BOOST_PP_INC(n), m_a ) ) ; \
  } \
\
  BOOST_PP_REPEAT( BOOST_PP_INC(n), BOOST_DEFINE_INPLACE_FACTORY_CLASS_MEMBER_DECL, _) \
} ; \
\
template< BOOST_PP_ENUM_PARAMS(BOOST_PP_INC(n),class A) > \
BOOST_PP_CAT(in_place_factory, BOOST_PP_INC(n) ) < BOOST_PP_ENUM_PARAMS( BOOST_PP_INC(n), A ) > \
in_place ( BOOST_PP_ENUM_BINARY_PARAMS(BOOST_PP_INC(n),A, const& a) ) \
{ \
  return BOOST_PP_CAT(in_place_factory, BOOST_PP_INC(n) ) < BOOST_PP_ENUM_PARAMS( BOOST_PP_INC(n), A ) > \
           ( BOOST_PP_ENUM_PARAMS( BOOST_PP_INC(n), a ) ) ; \
} ; \

BOOST_PP_REPEAT( BOOST_MAX_INPLACE_FACTORY_ARITY, BOOST_DEFINE_INPLACE_FACTORY_CLASS, BOOST_PP_EMPTY() )

} // namespace boost

#include <boost/utility/detail/in_place_factory_suffix.hpp>

#endif

Boost C++ Libraries

boost/utility/in_place_factory.hpp