boost_mpl/include/boost/mpl/aux_/integral_wrapper.hpp

// + file: boost/mpl/aux_/intergal_wrapper.hpp
// + last modified: 12/apr/03

// Copyright (c) 2000-03
// Aleksey Gurtovoy
//
// Permission to use, copy, modify, distribute and sell this software
// and its documentation for any purpose is hereby granted without fee, 
// provided that the above copyright notice appears in all copies and 
// that both the copyright notice and this permission notice appear in 
// supporting documentation. No representations are made about the 
// suitability of this software for any purpose. It is provided "as is" 
// without express or implied warranty.
//
// See http://www.boost.org/libs/mpl for documentation.

// no include guards, the header is intended for multiple inclusion!

#include "boost/mpl/aux_/static_cast.hpp"
#include "boost/mpl/aux_/config/nttp.hpp"
#include "boost/mpl/aux_/config/static_constant.hpp"
#include "boost/mpl/aux_/config/workaround.hpp"

#include "boost/preprocessor/cat.hpp"

#if !defined(AUX_WRAPPER_NAME)
#   define AUX_WRAPPER_NAME BOOST_PP_CAT(AUX_WRAPPER_VALUE_TYPE,_)
#endif

#if !defined(AUX_WRAPPER_PARAMS)
#   define AUX_WRAPPER_PARAMS(N) BOOST_MPL_AUX_NTTP_DECL(AUX_WRAPPER_VALUE_TYPE, N)
#endif

#if !defined(AUX_WRAPPER_INST)
#   if BOOST_WORKAROUND(__MWERKS__, <= 0x2407)
#       define AUX_WRAPPER_INST(value) AUX_WRAPPER_NAME< value >
#   else 
#       define AUX_WRAPPER_INST(value) mpl::AUX_WRAPPER_NAME< value >
#   endif
#endif

namespace boost { namespace mpl {

template< AUX_WRAPPER_PARAMS(N) >
struct AUX_WRAPPER_NAME
{
    BOOST_STATIC_CONSTANT(AUX_WRAPPER_VALUE_TYPE, value = N);
// agurt, 08/mar/03: SGI MIPSpro C++ workaround, have to #ifdef because some 
// other compilers (e.g. MSVC) are not particulary happy about it
#if BOOST_WORKAROUND(__EDG_VERSION__, <= 238)
    typedef struct AUX_WRAPPER_NAME type;
#else
    typedef AUX_WRAPPER_NAME type;
#endif
    typedef AUX_WRAPPER_VALUE_TYPE value_type;

// have to #ifdef here: some compilers don't like the 'N + 1' form (MSVC),
// while some other don't like 'value + 1' (Borland), and some don't like
// either
#if BOOST_WORKAROUND(__EDG_VERSION__, <= 243)
 private:
    BOOST_STATIC_CONSTANT(AUX_WRAPPER_VALUE_TYPE, next_value = BOOST_MPL_AUX_STATIC_CAST(AUX_WRAPPER_VALUE_TYPE, (N + 1)));
    BOOST_STATIC_CONSTANT(AUX_WRAPPER_VALUE_TYPE, prior_value = BOOST_MPL_AUX_STATIC_CAST(AUX_WRAPPER_VALUE_TYPE, (N - 1)));
 public:
    typedef AUX_WRAPPER_INST(next_value) next;
    typedef AUX_WRAPPER_INST(prior_value) prior;
#elif BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x561)) \
    || BOOST_WORKAROUND(__IBMCPP__, BOOST_TESTED_AT(502)) \
    || BOOST_WORKAROUND(__HP_aCC, BOOST_TESTED_AT(53800))
    typedef AUX_WRAPPER_INST( BOOST_MPL_AUX_STATIC_CAST(AUX_WRAPPER_VALUE_TYPE, (N + 1)) ) next;
    typedef AUX_WRAPPER_INST( BOOST_MPL_AUX_STATIC_CAST(AUX_WRAPPER_VALUE_TYPE, (N - 1)) ) prior;
#else
    typedef AUX_WRAPPER_INST( BOOST_MPL_AUX_STATIC_CAST(AUX_WRAPPER_VALUE_TYPE, (value + 1)) ) next;
    typedef AUX_WRAPPER_INST( BOOST_MPL_AUX_STATIC_CAST(AUX_WRAPPER_VALUE_TYPE, (value - 1)) ) prior;
#endif

    // enables uniform function call syntax for families of overloaded 
    // functions that return objects of both arithmetic ('int', 'long',
    // 'double', etc.) and wrapped integral types (for an example, see 
    // "mpl/example/power.cpp")
    operator AUX_WRAPPER_VALUE_TYPE() const { return static_cast<AUX_WRAPPER_VALUE_TYPE>(this->value); } 
};

#if !defined(BOOST_NO_INCLASS_MEMBER_INITIALIZATION)
template< AUX_WRAPPER_PARAMS(N) >
AUX_WRAPPER_VALUE_TYPE const AUX_WRAPPER_INST(N)::value;
#endif

}} // namespace boost::mpl

#undef AUX_WRAPPER_NAME
#undef AUX_WRAPPER_PARAMS
#undef AUX_WRAPPER_INST
#undef AUX_WRAPPER_VALUE_TYPE