mpl/aux_/count_args.hpp

0001
0002 // NO INCLUDE GUARDS, THE HEADER IS INTENDED FOR MULTIPLE INCLUSION
0003
0004 // Copyright Aleksey Gurtovoy 2000-2004
0005 //
0006 // Distributed under the Boost Software License, Version 1.0.
0007 // (See accompanying file LICENSE_1_0.txt or copy at
0008 // http://www.boost.org/LICENSE_1_0.txt)
0009 //
0010 // See http://www.boost.org/libs/mpl for documentation.
0011
0012 // $Id$
0013 // $Date$
0014 // $Revision$
0015
0016 #include <boost/preprocessor/expr_if.hpp>
0017 #include <boost/preprocessor/inc.hpp>
0018 #include <boost/preprocessor/cat.hpp>
0019
0020 #if !defined(AUX778076_COUNT_ARGS_PARAM_NAME)
0021 #   define AUX778076_COUNT_ARGS_PARAM_NAME T
0022 #endif
0023
0024 #if !defined(AUX778076_COUNT_ARGS_TEMPLATE_PARAM)
0025 #   define AUX778076_COUNT_ARGS_TEMPLATE_PARAM typename AUX778076_COUNT_ARGS_PARAM_NAME
0026 #endif
0027
0028 // local macros, #undef-ined at the end of the header
0029
0030 #if !defined(AUX778076_COUNT_ARGS_USE_STANDARD_PP_PRIMITIVES)
0031
0032 #   include <boost/mpl/aux_/preprocessor/repeat.hpp>
0033 #   include <boost/mpl/aux_/preprocessor/params.hpp>
0034
0035 #   define AUX778076_COUNT_ARGS_REPEAT BOOST_MPL_PP_REPEAT
0036 #   define AUX778076_COUNT_ARGS_PARAMS(param) \
0037     BOOST_MPL_PP_PARAMS( \
0038           AUX778076_COUNT_ARGS_ARITY \
0039         , param \
0040         ) \
0041     /**/
0042
0043 #else
0044
0045 #   include <boost/preprocessor/enum_shifted_params.hpp>
0046 #   include <boost/preprocessor/repeat.hpp>
0047 #   include <boost/preprocessor/inc.hpp>
0048
0049 #   define AUX778076_COUNT_ARGS_REPEAT BOOST_PP_REPEAT
0050 #   define AUX778076_COUNT_ARGS_PARAMS(param) \
0051     BOOST_PP_ENUM_SHIFTED_PARAMS( \
0052           BOOST_PP_INC(AUX778076_COUNT_ARGS_ARITY) \
0053         , param \
0054         ) \
0055     /**/
0056
0057 #endif // AUX778076_COUNT_ARGS_USE_STANDARD_PP_PRIMITIVES
0058
0059
0060 #define AUX778076_IS_ARG_TEMPLATE_NAME \
0061     BOOST_PP_CAT(is_,BOOST_PP_CAT(AUX778076_COUNT_ARGS_PREFIX,_arg)) \
0062 /**/
0063
0064 #define AUX778076_COUNT_ARGS_FUNC(unused, i, param) \
0065     BOOST_PP_EXPR_IF(i, +) \
0066     AUX778076_IS_ARG_TEMPLATE_NAME<BOOST_PP_CAT(param,BOOST_PP_INC(i))>::value \
0067 /**/
0068
0069 // is_<xxx>_arg
0070 template< AUX778076_COUNT_ARGS_TEMPLATE_PARAM >
0071 struct AUX778076_IS_ARG_TEMPLATE_NAME
0072 {
0073     BOOST_STATIC_CONSTANT(bool, value = true);
0074 };
0075
0076 template<>
0077 struct AUX778076_IS_ARG_TEMPLATE_NAME<AUX778076_COUNT_ARGS_DEFAULT>
0078 {
0079     BOOST_STATIC_CONSTANT(bool, value = false);
0080 };
0081
0082 // <xxx>_count_args
0083 template<
0084       AUX778076_COUNT_ARGS_PARAMS(AUX778076_COUNT_ARGS_TEMPLATE_PARAM)
0085     >
0086 struct BOOST_PP_CAT(AUX778076_COUNT_ARGS_PREFIX,_count_args)
0087 {
0088     BOOST_STATIC_CONSTANT(int, value = AUX778076_COUNT_ARGS_REPEAT(
0089           AUX778076_COUNT_ARGS_ARITY
0090         , AUX778076_COUNT_ARGS_FUNC
0091         , AUX778076_COUNT_ARGS_PARAM_NAME
0092         ));
0093 };
0094
0095 #undef AUX778076_COUNT_ARGS_FUNC
0096 #undef AUX778076_IS_ARG_TEMPLATE_NAME
0097 #undef AUX778076_COUNT_ARGS_PARAMS
0098 #undef AUX778076_COUNT_ARGS_REPEAT
0099
0100 #undef AUX778076_COUNT_ARGS_ARITY
0101 #undef AUX778076_COUNT_ARGS_DEFAULT
0102 #undef AUX778076_COUNT_ARGS_PREFIX
0103 #undef AUX778076_COUNT_ARGS_USE_STANDARD_PP_PRIMITIVES
0104 #undef AUX778076_COUNT_ARGS_TEMPLATE_PARAM
0105 #undef AUX778076_COUNT_ARGS_PARAM_NAME