File indexing completed on 2025-01-18 09:53:50
0001
0002
0003
0004
0005
0006
0007
0008 #ifndef BOOST_XPRESSIVE_DETAIL_STATIC_TRANSFORMS_AS_ALTERNATE_HPP_EAN_04_01_2007
0009 #define BOOST_XPRESSIVE_DETAIL_STATIC_TRANSFORMS_AS_ALTERNATE_HPP_EAN_04_01_2007
0010
0011
0012 #if defined(_MSC_VER)
0013 # pragma once
0014 #endif
0015
0016 #include <boost/config.hpp>
0017 #include <boost/mpl/assert.hpp>
0018 #include <boost/type_traits/is_same.hpp>
0019 #include <boost/proto/core.hpp>
0020 #include <boost/xpressive/detail/detail_fwd.hpp>
0021 #include <boost/xpressive/detail/static/static.hpp>
0022 #include <boost/xpressive/detail/core/matcher/alternate_matcher.hpp>
0023 #include <boost/xpressive/detail/utility/cons.hpp>
0024
0025 namespace boost { namespace xpressive
0026 {
0027 namespace detail
0028 {
0029
0030
0031
0032
0033 template<typename Head, typename Tail>
0034 struct alternates_list
0035 : fusion::cons<Head, Tail>
0036 {
0037 BOOST_STATIC_CONSTANT(std::size_t, width = Head::width == Tail::width ? Head::width : detail::unknown_width::value);
0038 BOOST_STATIC_CONSTANT(bool, pure = Head::pure && Tail::pure);
0039
0040 alternates_list(Head const &head, Tail const &tail)
0041 : fusion::cons<Head, Tail>(head, tail)
0042 {
0043 }
0044 };
0045
0046 template<typename Head>
0047 struct alternates_list<Head, fusion::nil>
0048 : fusion::cons<Head, fusion::nil>
0049 {
0050 BOOST_STATIC_CONSTANT(std::size_t, width = Head::width);
0051 BOOST_STATIC_CONSTANT(bool, pure = Head::pure);
0052
0053 alternates_list(Head const &head, fusion::nil const &tail)
0054 : fusion::cons<Head, fusion::nil>(head, tail)
0055 {
0056 }
0057 };
0058 }
0059
0060 namespace grammar_detail
0061 {
0062
0063
0064 template<typename Grammar, typename Callable = proto::callable>
0065 struct in_alternate_list : proto::transform<in_alternate_list<Grammar, Callable> >
0066 {
0067 template<typename Expr, typename State, typename Data>
0068 struct impl : proto::transform_impl<Expr, State, Data>
0069 {
0070 typedef
0071 detail::alternates_list<
0072 typename Grammar::template impl<
0073 Expr
0074 , detail::alternate_end_xpression
0075 , Data
0076 >::result_type
0077 , State
0078 >
0079 result_type;
0080
0081 result_type operator ()(
0082 typename impl::expr_param expr
0083 , typename impl::state_param state
0084 , typename impl::data_param data
0085 ) const
0086 {
0087 return result_type(
0088 typename Grammar::template impl<Expr, detail::alternate_end_xpression, Data>()(
0089 expr
0090 , detail::alternate_end_xpression()
0091 , data
0092 )
0093 , state
0094 );
0095 }
0096 };
0097 };
0098
0099
0100
0101 template<typename Grammar, typename Callable = proto::callable>
0102 struct as_alternate_matcher : proto::transform<as_alternate_matcher<Grammar, Callable> >
0103 {
0104 template<typename Expr, typename State, typename Data>
0105 struct impl : proto::transform_impl<Expr, State, Data>
0106 {
0107 typedef typename impl::data data_type;
0108 typedef
0109 detail::alternate_matcher<
0110 typename Grammar::template impl<Expr, State, Data>::result_type
0111 , typename data_type::traits_type
0112 >
0113 result_type;
0114
0115 result_type operator ()(
0116 typename impl::expr_param expr
0117 , typename impl::state_param state
0118 , typename impl::data_param data
0119 ) const
0120 {
0121 return result_type(
0122 typename Grammar::template impl<Expr, State, Data>()(expr, state, data)
0123 );
0124 }
0125 };
0126 };
0127 }
0128
0129 }}
0130
0131 #endif