| #ifndef BOOST_PP_IS_ITERATING | |
| /////////////////////////////////////////////////////////////////////////////// | |
| /// \file matches.hpp | |
| /// Contains definition of matches\<\> metafunction for determining if | |
| /// a given expression matches a given pattern. | |
| // | |
| // Copyright 2008 Eric Niebler. 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) | |
| #ifndef BOOST_PROTO_MATCHES_HPP_EAN_11_03_2006 | |
| #define BOOST_PROTO_MATCHES_HPP_EAN_11_03_2006 | |
| #include <boost/config.hpp> | |
| #include <boost/detail/workaround.hpp> | |
| #include <boost/preprocessor/cat.hpp> | |
| #include <boost/preprocessor/arithmetic/dec.hpp> | |
| #include <boost/preprocessor/arithmetic/sub.hpp> | |
| #include <boost/preprocessor/iteration/iterate.hpp> | |
| #include <boost/preprocessor/facilities/intercept.hpp> | |
| #include <boost/preprocessor/punctuation/comma_if.hpp> | |
| #include <boost/preprocessor/repetition/enum.hpp> | |
| #include <boost/preprocessor/repetition/enum_params.hpp> | |
| #include <boost/preprocessor/repetition/enum_shifted.hpp> | |
| #include <boost/preprocessor/repetition/enum_binary_params.hpp> | |
| #include <boost/preprocessor/repetition/enum_shifted_params.hpp> | |
| #include <boost/preprocessor/repetition/enum_trailing_params.hpp> | |
| #include <boost/preprocessor/repetition/enum_params_with_a_default.hpp> | |
| #include <boost/preprocessor/repetition/repeat.hpp> | |
| #include <boost/config.hpp> | |
| #include <boost/mpl/logical.hpp> | |
| #include <boost/mpl/eval_if.hpp> | |
| #include <boost/mpl/aux_/template_arity.hpp> | |
| #include <boost/mpl/aux_/lambda_arity_param.hpp> | |
| #include <boost/utility/enable_if.hpp> | |
| #if BOOST_WORKAROUND(BOOST_MSVC, == 1310) | |
| #include <boost/type_traits/is_array.hpp> | |
| #endif | |
| #include <boost/type_traits/is_const.hpp> | |
| #include <boost/type_traits/is_convertible.hpp> | |
| #include <boost/type_traits/is_reference.hpp> | |
| #include <boost/type_traits/is_pointer.hpp> | |
| #include <boost/proto/proto_fwd.hpp> | |
| #include <boost/proto/traits.hpp> | |
| #include <boost/proto/transform/when.hpp> | |
| #include <boost/proto/transform/impl.hpp> | |
| // Some compilers (like GCC) need extra help figuring out a template's arity. | |
| // I use MPL's BOOST_MPL_AUX_LAMBDA_ARITY_PARAM() macro to disambiguate, which | |
| // which is controlled by the BOOST_MPL_LIMIT_METAFUNCTION_ARITY macro. If | |
| // You define BOOST_PROTO_MAX_ARITY to be greater than | |
| // BOOST_MPL_LIMIT_METAFUNCTION_ARITY on these compilers, things don't work. | |
| // You must define BOOST_MPL_LIMIT_METAFUNCTION_ARITY to be greater. | |
| #ifdef BOOST_MPL_CFG_EXTENDED_TEMPLATE_PARAMETERS_MATCHING | |
| # if BOOST_PROTO_MAX_ARITY > BOOST_MPL_LIMIT_METAFUNCTION_ARITY | |
| # error BOOST_MPL_LIMIT_METAFUNCTION_ARITY must be at least as large as BOOST_PROTO_MAX_ARITY | |
| # endif | |
| #endif | |
| #if defined(_MSC_VER) && (_MSC_VER >= 1020) | |
| # pragma warning(push) | |
| # pragma warning(disable:4305) // 'specialization' : truncation from 'const int' to 'bool' | |
| #endif | |
| namespace boost { namespace proto | |
| { | |
| namespace detail | |
| { | |
| template<typename Expr, typename BasicExpr, typename Grammar> | |
| struct matches_; | |
| template<bool B, typename Pred> | |
| struct and_2; | |
| template<typename And, typename Expr, typename State, typename Data> | |
| struct _and_impl; | |
| template<typename T, typename U> | |
| struct array_matches | |
| : mpl::false_ | |
| {}; | |
| template<typename T, std::size_t M> | |
| struct array_matches<T[M], T *> | |
| : mpl::true_ | |
| {}; | |
| template<typename T, std::size_t M> | |
| struct array_matches<T[M], T const *> | |
| : mpl::true_ | |
| {}; | |
| template<typename T, std::size_t M> | |
| struct array_matches<T[M], T[proto::N]> | |
| : mpl::true_ | |
| {}; | |
| template<typename T, typename U | |
| BOOST_MPL_AUX_LAMBDA_ARITY_PARAM(long Arity = mpl::aux::template_arity<U>::value) | |
| > | |
| struct lambda_matches | |
| : mpl::false_ | |
| {}; | |
| template<typename T> | |
| struct lambda_matches<T, proto::_ BOOST_MPL_AUX_LAMBDA_ARITY_PARAM(-1)> | |
| : mpl::true_ | |
| {}; | |
| template<typename T> | |
| struct lambda_matches<T, T BOOST_MPL_AUX_LAMBDA_ARITY_PARAM(-1)> | |
| : mpl::true_ | |
| {}; | |
| template<typename T, std::size_t M, typename U> | |
| struct lambda_matches<T[M], U BOOST_MPL_AUX_LAMBDA_ARITY_PARAM(-1)> | |
| : array_matches<T[M], U> | |
| {}; | |
| template<typename T, std::size_t M> | |
| struct lambda_matches<T[M], _ BOOST_MPL_AUX_LAMBDA_ARITY_PARAM(-1)> | |
| : mpl::true_ | |
| {}; | |
| template<typename T, std::size_t M> | |
| struct lambda_matches<T[M], T[M] BOOST_MPL_AUX_LAMBDA_ARITY_PARAM(-1)> | |
| : mpl::true_ | |
| {}; | |
| template<template<typename> class T, typename Expr0, typename Grammar0> | |
| struct lambda_matches<T<Expr0>, T<Grammar0> BOOST_MPL_AUX_LAMBDA_ARITY_PARAM(1) > | |
| : lambda_matches<Expr0, Grammar0> | |
| {}; | |
| // vararg_matches_impl | |
| template<typename Args1, typename Back, long From, long To> | |
| struct vararg_matches_impl; | |
| // vararg_matches | |
| template<typename Expr, typename Args1, typename Args2, typename Back, bool Can, bool Zero, typename Void = void> | |
| struct vararg_matches | |
| : mpl::false_ | |
| {}; | |
| template<typename Expr, typename Args1, typename Args2, typename Back> | |
| struct vararg_matches<Expr, Args1, Args2, Back, true, true, typename Back::proto_is_vararg_> | |
| : matches_< | |
| Expr | |
| , proto::basic_expr<ignore, Args1, Args1::arity> | |
| , proto::basic_expr<ignore, Args2, Args1::arity> | |
| > | |
| {}; | |
| template<typename Expr, typename Args1, typename Args2, typename Back> | |
| struct vararg_matches<Expr, Args1, Args2, Back, true, false, typename Back::proto_is_vararg_> | |
| : and_2< | |
| matches_< | |
| Expr | |
| , proto::basic_expr<ignore, Args1, Args2::arity> | |
| , proto::basic_expr<ignore, Args2, Args2::arity> | |
| >::value | |
| , vararg_matches_impl<Args1, typename Back::proto_grammar, Args2::arity + 1, Args1::arity> | |
| > | |
| {}; | |
| // How terminal_matches<> handles references and cv-qualifiers. | |
| // The cv and ref matter *only* if the grammar has a top-level ref. | |
| // | |
| // Expr | Grammar | Matches? | |
| // ------------------------------------- | |
| // T T yes | |
| // T & T yes | |
| // T const & T yes | |
| // T T & no | |
| // T & T & yes | |
| // T const & T & no | |
| // T T const & no | |
| // T & T const & no | |
| // T const & T const & yes | |
| template<typename T, typename U> | |
| struct is_cv_ref_compatible | |
| : mpl::true_ | |
| {}; | |
| template<typename T, typename U> | |
| struct is_cv_ref_compatible<T, U &> | |
| : mpl::false_ | |
| {}; | |
| template<typename T, typename U> | |
| struct is_cv_ref_compatible<T &, U &> | |
| : mpl::bool_<is_const<T>::value == is_const<U>::value> | |
| {}; | |
| #if BOOST_WORKAROUND(BOOST_MSVC, == 1310) | |
| // MSVC-7.1 has lots of problems with array types that have been | |
| // deduced. Partially specializing terminal_matches<> on array types | |
| // doesn't seem to work. | |
| template< | |
| typename T | |
| , typename U | |
| , bool B = is_array<BOOST_PROTO_UNCVREF(T)>::value | |
| > | |
| struct terminal_array_matches | |
| : mpl::false_ | |
| {}; | |
| template<typename T, typename U, std::size_t M> | |
| struct terminal_array_matches<T, U(&)[M], true> | |
| : is_convertible<T, U(&)[M]> | |
| {}; | |
| template<typename T, typename U> | |
| struct terminal_array_matches<T, U(&)[proto::N], true> | |
| : is_convertible<T, U *> | |
| {}; | |
| template<typename T, typename U> | |
| struct terminal_array_matches<T, U *, true> | |
| : is_convertible<T, U *> | |
| {}; | |
| // terminal_matches | |
| template<typename T, typename U> | |
| struct terminal_matches | |
| : mpl::or_< | |
| mpl::and_< | |
| is_cv_ref_compatible<T, U> | |
| , lambda_matches< | |
| BOOST_PROTO_UNCVREF(T) | |
| , BOOST_PROTO_UNCVREF(U) | |
| > | |
| > | |
| , terminal_array_matches<T, U> | |
| > | |
| {}; | |
| #else | |
| // terminal_matches | |
| template<typename T, typename U> | |
| struct terminal_matches | |
| : mpl::and_< | |
| is_cv_ref_compatible<T, U> | |
| , lambda_matches< | |
| BOOST_PROTO_UNCVREF(T) | |
| , BOOST_PROTO_UNCVREF(U) | |
| > | |
| > | |
| {}; | |
| template<typename T, std::size_t M> | |
| struct terminal_matches<T(&)[M], T(&)[proto::N]> | |
| : mpl::true_ | |
| {}; | |
| template<typename T, std::size_t M> | |
| struct terminal_matches<T(&)[M], T *> | |
| : mpl::true_ | |
| {}; | |
| // Avoid ambiguity errors on MSVC | |
| #if BOOST_WORKAROUND(BOOST_MSVC, BOOST_TESTED_AT(1500)) | |
| template<typename T, std::size_t M> | |
| struct terminal_matches<T const (&)[M], T const[M]> | |
| : mpl::true_ | |
| {}; | |
| #endif | |
| #endif | |
| template<typename T> | |
| struct terminal_matches<T, T> | |
| : mpl::true_ | |
| {}; | |
| template<typename T> | |
| struct terminal_matches<T &, T> | |
| : mpl::true_ | |
| {}; | |
| template<typename T> | |
| struct terminal_matches<T const &, T> | |
| : mpl::true_ | |
| {}; | |
| template<typename T> | |
| struct terminal_matches<T, proto::_> | |
| : mpl::true_ | |
| {}; | |
| template<typename T> | |
| struct terminal_matches<T, exact<T> > | |
| : mpl::true_ | |
| {}; | |
| template<typename T, typename U> | |
| struct terminal_matches<T, proto::convertible_to<U> > | |
| : is_convertible<T, U> | |
| {}; | |
| // matches_ | |
| template<typename Expr, typename BasicExpr, typename Grammar> | |
| struct matches_ | |
| : mpl::false_ | |
| {}; | |
| template<typename Expr, typename BasicExpr> | |
| struct matches_< Expr, BasicExpr, proto::_ > | |
| : mpl::true_ | |
| {}; | |
| template<typename Expr, typename Tag, typename Args1, long N1, typename Args2, long N2> | |
| struct matches_< Expr, proto::basic_expr<Tag, Args1, N1>, proto::basic_expr<Tag, Args2, N2> > | |
| : vararg_matches< Expr, Args1, Args2, typename Args2::back_, (N1+2 > N2), (N2 > N1) > | |
| {}; | |
| template<typename Expr, typename Tag, typename Args1, long N1, typename Args2, long N2> | |
| struct matches_< Expr, proto::basic_expr<Tag, Args1, N1>, proto::basic_expr<proto::_, Args2, N2> > | |
| : vararg_matches< Expr, Args1, Args2, typename Args2::back_, (N1+2 > N2), (N2 > N1) > | |
| {}; | |
| template<typename Expr, typename Tag, typename Args1, typename Args2> | |
| struct matches_< Expr, proto::basic_expr<Tag, Args1, 0>, proto::basic_expr<Tag, Args2, 0> > | |
| : terminal_matches<typename Args1::child0, typename Args2::child0> | |
| {}; | |
| template<typename Expr, typename Tag, typename Args1, typename Args2, long N2> | |
| struct matches_< Expr, proto::basic_expr<Tag, Args1, 0>, proto::basic_expr<proto::_, Args2, N2> > | |
| : mpl::false_ | |
| {}; | |
| template<typename Expr, typename Tag, typename Args1, typename Args2> | |
| struct matches_< Expr, proto::basic_expr<Tag, Args1, 0>, proto::basic_expr<proto::_, Args2, 0> > | |
| : terminal_matches<typename Args1::child0, typename Args2::child0> | |
| {}; | |
| template<typename Expr, typename Tag, typename Args1, typename Args2> | |
| struct matches_< Expr, proto::basic_expr<Tag, Args1, 1>, proto::basic_expr<Tag, Args2, 1> > | |
| : matches_< | |
| typename detail::expr_traits<typename Args1::child0>::value_type::proto_derived_expr | |
| , typename detail::expr_traits<typename Args1::child0>::value_type::proto_grammar | |
| , typename Args2::child0::proto_grammar | |
| > | |
| {}; | |
| template<typename Expr, typename Tag, typename Args1, typename Args2> | |
| struct matches_< Expr, proto::basic_expr<Tag, Args1, 1>, proto::basic_expr<proto::_, Args2, 1> > | |
| : matches_< | |
| typename detail::expr_traits<typename Args1::child0>::value_type::proto_derived_expr | |
| , typename detail::expr_traits<typename Args1::child0>::value_type::proto_grammar | |
| , typename Args2::child0::proto_grammar | |
| > | |
| {}; | |
| #define BOOST_PROTO_MATCHES_N_FUN(Z, N, DATA) \ | |
| matches_< \ | |
| typename detail::expr_traits<typename Args1::BOOST_PP_CAT(child, N)>::value_type::proto_derived_expr \ | |
| , typename detail::expr_traits<typename Args1::BOOST_PP_CAT(child, N)>::value_type::proto_grammar \ | |
| , typename Args2::BOOST_PP_CAT(child, N)::proto_grammar \ | |
| > | |
| #define BOOST_PROTO_DEFINE_MATCHES(Z, N, DATA) \ | |
| matches_< \ | |
| Expr \ | |
| , BasicExpr \ | |
| , typename BOOST_PP_CAT(G, N)::proto_grammar \ | |
| > | |
| #define BOOST_PROTO_DEFINE_LAMBDA_MATCHES(Z, N, DATA) \ | |
| lambda_matches< \ | |
| BOOST_PP_CAT(Expr, N) \ | |
| , BOOST_PP_CAT(Grammar, N) \ | |
| > | |
| #if BOOST_PROTO_MAX_LOGICAL_ARITY > BOOST_PROTO_MAX_ARITY | |
| #define BOOST_PP_ITERATION_PARAMS_1 (4, (2, BOOST_PROTO_MAX_LOGICAL_ARITY, <boost/proto/matches.hpp>, 1)) | |
| #else | |
| #define BOOST_PP_ITERATION_PARAMS_1 (4, (2, BOOST_PROTO_MAX_ARITY, <boost/proto/matches.hpp>, 1)) | |
| #endif | |
| #include BOOST_PP_ITERATE() | |
| #define BOOST_PP_ITERATION_PARAMS_1 (4, (2, BOOST_PROTO_MAX_ARITY, <boost/proto/matches.hpp>, 2)) | |
| #include BOOST_PP_ITERATE() | |
| #undef BOOST_PROTO_MATCHES_N_FUN | |
| #undef BOOST_PROTO_DEFINE_MATCHES | |
| #undef BOOST_PROTO_DEFINE_LAMBDA_MATCHES | |
| // handle proto::if_ | |
| template<typename Expr, typename Tag, typename Args, long Arity, typename If, typename Then, typename Else> | |
| struct matches_<Expr, proto::basic_expr<Tag, Args, Arity>, proto::if_<If, Then, Else> > | |
| : mpl::eval_if_c< | |
| remove_reference< | |
| typename when<_, If>::template impl<Expr, int, int>::result_type | |
| >::type::value | |
| , matches_<Expr, proto::basic_expr<Tag, Args, Arity>, typename Then::proto_grammar> | |
| , matches_<Expr, proto::basic_expr<Tag, Args, Arity>, typename Else::proto_grammar> | |
| >::type | |
| { | |
| typedef | |
| typename mpl::if_c< | |
| remove_reference< | |
| typename when<_, If>::template impl<Expr, int, int>::result_type | |
| >::type::value | |
| , Then | |
| , Else | |
| >::type | |
| which; | |
| }; | |
| // handle degenerate cases of proto::or_ | |
| template<typename Expr, typename BasicExpr> | |
| struct matches_<Expr, BasicExpr, or_<> > | |
| : mpl::false_ | |
| { | |
| typedef not_<_> which; | |
| }; | |
| template<typename Expr, typename BasicExpr, typename G0> | |
| struct matches_<Expr, BasicExpr, or_<G0> > | |
| : matches_<Expr, BasicExpr, typename G0::proto_grammar> | |
| { | |
| typedef G0 which; | |
| }; | |
| // handle degenerate cases of proto::and_ | |
| template<typename Expr, typename BasicExpr> | |
| struct matches_<Expr, BasicExpr, and_<> > | |
| : mpl::true_ | |
| {}; | |
| template<typename Expr, typename BasicExpr, typename G0> | |
| struct matches_<Expr, BasicExpr, and_<G0> > | |
| : matches_<Expr, BasicExpr, typename G0::proto_grammar> | |
| {}; | |
| // handle proto::not_ | |
| template<typename Expr, typename BasicExpr, typename Grammar> | |
| struct matches_<Expr, BasicExpr, not_<Grammar> > | |
| : mpl::not_<matches_<Expr, BasicExpr, typename Grammar::proto_grammar> > | |
| {}; | |
| // handle proto::switch_ | |
| template<typename Expr, typename Tag, typename Args, long Arity, typename Cases> | |
| struct matches_<Expr, proto::basic_expr<Tag, Args, Arity>, switch_<Cases> > | |
| : matches_< | |
| Expr | |
| , proto::basic_expr<Tag, Args, Arity> | |
| , typename Cases::template case_<Tag>::proto_grammar | |
| > | |
| { | |
| typedef typename Cases::template case_<Tag> which; | |
| }; | |
| } | |
| /// \brief A Boolean metafunction that evaluates whether a given | |
| /// expression type matches a grammar. | |
| /// | |
| /// <tt>matches\<Expr,Grammar\></tt> inherits (indirectly) from | |
| /// \c mpl::true_ if <tt>Expr::proto_grammar</tt> matches | |
| /// <tt>Grammar::proto_grammar</tt>, and from \c mpl::false_ | |
| /// otherwise. | |
| /// | |
| /// Non-terminal expressions are matched against a grammar | |
| /// according to the following rules: | |
| /// | |
| /// \li The wildcard pattern, \c _, matches any expression. | |
| /// \li An expression <tt>expr\<AT, listN\<A0,A1,...An\> \></tt> | |
| /// matches a grammar <tt>expr\<BT, listN\<B0,B1,...Bn\> \></tt> | |
| /// if \c BT is \c _ or \c AT, and if \c Ax matches \c Bx for | |
| /// each \c x in <tt>[0,n)</tt>. | |
| /// \li An expression <tt>expr\<AT, listN\<A0,...An,U0,...Um\> \></tt> | |
| /// matches a grammar <tt>expr\<BT, listM\<B0,...Bn,vararg\<V\> \> \></tt> | |
| /// if \c BT is \c _ or \c AT, and if \c Ax matches \c Bx | |
| /// for each \c x in <tt>[0,n)</tt> and if \c Ux matches \c V | |
| /// for each \c x in <tt>[0,m)</tt>. | |
| /// \li An expression \c E matches <tt>or_\<B0,B1,...Bn\></tt> if \c E | |
| /// matches some \c Bx for \c x in <tt>[0,n)</tt>. | |
| /// \li An expression \c E matches <tt>and_\<B0,B1,...Bn\></tt> if \c E | |
| /// matches all \c Bx for \c x in <tt>[0,n)</tt>. | |
| /// \li An expression \c E matches <tt>if_\<T,U,V\></tt> if | |
| /// <tt>boost::result_of\<when\<_,T\>(E,int,int)\>::type::value</tt> | |
| /// is \c true and \c E matches \c U; or, if | |
| /// <tt>boost::result_of\<when\<_,T\>(E,int,int)\>::type::value</tt> | |
| /// is \c false and \c E matches \c V. (Note: \c U defaults to \c _ | |
| /// and \c V defaults to \c not_\<_\>.) | |
| /// \li An expression \c E matches <tt>not_\<T\></tt> if \c E does | |
| /// not match \c T. | |
| /// \li An expression \c E matches <tt>switch_\<C\></tt> if | |
| /// \c E matches <tt>C::case_\<E::proto_tag\></tt>. | |
| /// | |
| /// A terminal expression <tt>expr\<AT,term\<A\> \></tt> matches | |
| /// a grammar <tt>expr\<BT,term\<B\> \></tt> if \c BT is \c AT or | |
| /// \c proto::_ and if one of the following is true: | |
| /// | |
| /// \li \c B is the wildcard pattern, \c _ | |
| /// \li \c A is \c B | |
| /// \li \c A is <tt>B &</tt> | |
| /// \li \c A is <tt>B const &</tt> | |
| /// \li \c B is <tt>exact\<A\></tt> | |
| /// \li \c B is <tt>convertible_to\<X\></tt> and | |
| /// <tt>is_convertible\<A,X\>::value</tt> is \c true. | |
| /// \li \c A is <tt>X[M]</tt> or <tt>X(&)[M]</tt> and | |
| /// \c B is <tt>X[proto::N]</tt>. | |
| /// \li \c A is <tt>X(&)[M]</tt> and \c B is <tt>X(&)[proto::N]</tt>. | |
| /// \li \c A is <tt>X[M]</tt> or <tt>X(&)[M]</tt> and | |
| /// \c B is <tt>X*</tt>. | |
| /// \li \c B lambda-matches \c A (see below). | |
| /// | |
| /// A type \c B lambda-matches \c A if one of the following is true: | |
| /// | |
| /// \li \c B is \c A | |
| /// \li \c B is the wildcard pattern, \c _ | |
| /// \li \c B is <tt>T\<B0,B1,...Bn\></tt> and \c A is | |
| /// <tt>T\<A0,A1,...An\></tt> and for each \c x in | |
| /// <tt>[0,n)</tt>, \c Ax and \c Bx are types | |
| /// such that \c Ax lambda-matches \c Bx | |
| template<typename Expr, typename Grammar> | |
| struct matches | |
| : detail::matches_< | |
| typename Expr::proto_derived_expr | |
| , typename Expr::proto_grammar | |
| , typename Grammar::proto_grammar | |
| > | |
| {}; | |
| /// INTERNAL ONLY | |
| /// | |
| template<typename Expr, typename Grammar> | |
| struct matches<Expr &, Grammar> | |
| : detail::matches_< | |
| typename Expr::proto_derived_expr | |
| , typename Expr::proto_grammar | |
| , typename Grammar::proto_grammar | |
| > | |
| {}; | |
| /// \brief A wildcard grammar element that matches any expression, | |
| /// and a transform that returns the current expression unchanged. | |
| /// | |
| /// The wildcard type, \c _, is a grammar element such that | |
| /// <tt>matches\<E,_\>::value</tt> is \c true for any expression | |
| /// type \c E. | |
| /// | |
| /// The wildcard can also be used as a stand-in for a template | |
| /// argument when matching terminals. For instance, the following | |
| /// is a grammar that will match any <tt>std::complex\<\></tt> | |
| /// terminal: | |
| /// | |
| /// \code | |
| /// BOOST_MPL_ASSERT(( | |
| /// matches< | |
| /// terminal<std::complex<double> >::type | |
| /// , terminal<std::complex< _ > > | |
| /// > | |
| /// )); | |
| /// \endcode | |
| /// | |
| /// When used as a transform, \c _ returns the current expression | |
| /// unchanged. For instance, in the following, \c _ is used with | |
| /// the \c fold\<\> transform to fold the children of a node: | |
| /// | |
| /// \code | |
| /// struct CountChildren | |
| /// : or_< | |
| /// // Terminals have no children | |
| /// when<terminal<_>, mpl::int_<0>()> | |
| /// // Use fold<> to count the children of non-terminals | |
| /// , otherwise< | |
| /// fold< | |
| /// _ // <-- fold the current expression | |
| /// , mpl::int_<0>() | |
| /// , mpl::plus<_state, mpl::int_<1> >() | |
| /// > | |
| /// > | |
| /// > | |
| /// {}; | |
| /// \endcode | |
| struct _ : transform<_> | |
| { | |
| typedef _ proto_grammar; | |
| template<typename Expr, typename State, typename Data> | |
| struct impl : transform_impl<Expr, State, Data> | |
| { | |
| typedef Expr result_type; | |
| /// \param expr An expression | |
| /// \return \c e | |
| #ifdef BOOST_PROTO_STRICT_RESULT_OF | |
| result_type | |
| #else | |
| typename impl::expr_param | |
| #endif | |
| operator()( | |
| typename impl::expr_param e | |
| , typename impl::state_param | |
| , typename impl::data_param | |
| ) const | |
| { | |
| return e; | |
| } | |
| }; | |
| }; | |
| namespace detail | |
| { | |
| template<typename Expr, typename State, typename Data> | |
| struct _and_impl<proto::and_<>, Expr, State, Data> | |
| : proto::_::impl<Expr, State, Data> | |
| {}; | |
| template<typename G0, typename Expr, typename State, typename Data> | |
| struct _and_impl<proto::and_<G0>, Expr, State, Data> | |
| : proto::when<proto::_, G0>::template impl<Expr, State, Data> | |
| {}; | |
| } | |
| /// \brief Inverts the set of expressions matched by a grammar. When | |
| /// used as a transform, \c not_\<\> returns the current expression | |
| /// unchanged. | |
| /// | |
| /// If an expression type \c E does not match a grammar \c G, then | |
| /// \c E \e does match <tt>not_\<G\></tt>. For example, | |
| /// <tt>not_\<terminal\<_\> \></tt> will match any non-terminal. | |
| template<typename Grammar> | |
| struct not_ : transform<not_<Grammar> > | |
| { | |
| typedef not_ proto_grammar; | |
| template<typename Expr, typename State, typename Data> | |
| struct impl : transform_impl<Expr, State, Data> | |
| { | |
| typedef Expr result_type; | |
| /// \param e An expression | |
| /// \pre <tt>matches\<Expr,not_\>::value</tt> is \c true. | |
| /// \return \c e | |
| #ifdef BOOST_PROTO_STRICT_RESULT_OF | |
| result_type | |
| #else | |
| typename impl::expr_param | |
| #endif | |
| operator()( | |
| typename impl::expr_param e | |
| , typename impl::state_param | |
| , typename impl::data_param | |
| ) const | |
| { | |
| return e; | |
| } | |
| }; | |
| }; | |
| /// \brief Used to select one grammar or another based on the result | |
| /// of a compile-time Boolean. When used as a transform, \c if_\<\> | |
| /// selects between two transforms based on a compile-time Boolean. | |
| /// | |
| /// When <tt>if_\<If,Then,Else\></tt> is used as a grammar, \c If | |
| /// must be a Proto transform and \c Then and \c Else must be grammars. | |
| /// An expression type \c E matches <tt>if_\<If,Then,Else\></tt> if | |
| /// <tt>boost::result_of\<when\<_,If\>(E,int,int)\>::type::value</tt> | |
| /// is \c true and \c E matches \c U; or, if | |
| /// <tt>boost::result_of\<when\<_,If\>(E,int,int)\>::type::value</tt> | |
| /// is \c false and \c E matches \c V. | |
| /// | |
| /// The template parameter \c Then defaults to \c _ | |
| /// and \c Else defaults to \c not\<_\>, so an expression type \c E | |
| /// will match <tt>if_\<If\></tt> if and only if | |
| /// <tt>boost::result_of\<when\<_,If\>(E,int,int)\>::type::value</tt> | |
| /// is \c true. | |
| /// | |
| /// \code | |
| /// // A grammar that only matches integral terminals, | |
| /// // using is_integral<> from Boost.Type_traits. | |
| /// struct IsIntegral | |
| /// : and_< | |
| /// terminal<_> | |
| /// , if_< is_integral<_value>() > | |
| /// > | |
| /// {}; | |
| /// \endcode | |
| /// | |
| /// When <tt>if_\<If,Then,Else\></tt> is used as a transform, \c If, | |
| /// \c Then and \c Else must be Proto transforms. When applying | |
| /// the transform to an expression \c E, state \c S and data \c V, | |
| /// if <tt>boost::result_of\<when\<_,If\>(E,S,V)\>::type::value</tt> | |
| /// is \c true then the \c Then transform is applied; otherwise | |
| /// the \c Else transform is applied. | |
| /// | |
| /// \code | |
| /// // Match a terminal. If the terminal is integral, return | |
| /// // mpl::true_; otherwise, return mpl::false_. | |
| /// struct IsIntegral2 | |
| /// : when< | |
| /// terminal<_> | |
| /// , if_< | |
| /// is_integral<_value>() | |
| /// , mpl::true_() | |
| /// , mpl::false_() | |
| /// > | |
| /// > | |
| /// {}; | |
| /// \endcode | |
| template< | |
| typename If | |
| , typename Then // = _ | |
| , typename Else // = not_<_> | |
| > | |
| struct if_ : transform<if_<If, Then, Else> > | |
| { | |
| typedef if_ proto_grammar; | |
| template<typename Expr, typename State, typename Data> | |
| struct impl : transform_impl<Expr, State, Data> | |
| { | |
| typedef | |
| typename when<_, If>::template impl<Expr, State, Data>::result_type | |
| condition; | |
| typedef | |
| typename mpl::if_c< | |
| remove_reference<condition>::type::value | |
| , when<_, Then> | |
| , when<_, Else> | |
| >::type | |
| which; | |
| typedef typename which::template impl<Expr, State, Data>::result_type result_type; | |
| /// \param e An expression | |
| /// \param s The current state | |
| /// \param d A data of arbitrary type | |
| /// \return <tt>which::impl<Expr, State, Data>()(e, s, d)</tt> | |
| result_type operator ()( | |
| typename impl::expr_param e | |
| , typename impl::state_param s | |
| , typename impl::data_param d | |
| ) const | |
| { | |
| return typename which::template impl<Expr, State, Data>()(e, s, d); | |
| } | |
| }; | |
| }; | |
| /// \brief For matching one of a set of alternate grammars. Alternates | |
| /// tried in order to avoid ambiguity. When used as a transform, \c or_\<\> | |
| /// applies the transform associated with the first grammar that matches | |
| /// the expression. | |
| /// | |
| /// An expression type \c E matches <tt>or_\<B0,B1,...Bn\></tt> if \c E | |
| /// matches any \c Bx for \c x in <tt>[0,n)</tt>. | |
| /// | |
| /// When applying <tt>or_\<B0,B1,...Bn\></tt> as a transform with an | |
| /// expression \c e of type \c E, state \c s and data \c d, it is | |
| /// equivalent to <tt>Bx()(e, s, d)</tt>, where \c x is the lowest | |
| /// number such that <tt>matches\<E,Bx\>::value</tt> is \c true. | |
| template<BOOST_PP_ENUM_PARAMS(BOOST_PROTO_MAX_LOGICAL_ARITY, typename G)> | |
| struct or_ : transform<or_<BOOST_PP_ENUM_PARAMS(BOOST_PROTO_MAX_LOGICAL_ARITY, G)> > | |
| { | |
| typedef or_ proto_grammar; | |
| /// \param e An expression | |
| /// \param s The current state | |
| /// \param d A data of arbitrary type | |
| /// \pre <tt>matches\<Expr,or_\>::value</tt> is \c true. | |
| /// \return <tt>which()(e, s, d)</tt>, where <tt>which</tt> is the | |
| /// sub-grammar that matched <tt>Expr</tt>. | |
| template<typename Expr, typename State, typename Data> | |
| struct impl | |
| : detail::matches_< | |
| typename Expr::proto_derived_expr | |
| , typename Expr::proto_grammar | |
| , or_ | |
| >::which::template impl<Expr, State, Data> | |
| {}; | |
| template<typename Expr, typename State, typename Data> | |
| struct impl<Expr &, State, Data> | |
| : detail::matches_< | |
| typename Expr::proto_derived_expr | |
| , typename Expr::proto_grammar | |
| , or_ | |
| >::which::template impl<Expr &, State, Data> | |
| {}; | |
| }; | |
| /// \brief For matching all of a set of grammars. When used as a | |
| /// transform, \c and_\<\> applies the transforms associated with | |
| /// the each grammar in the set, and returns the result of the last. | |
| /// | |
| /// An expression type \c E matches <tt>and_\<B0,B1,...Bn\></tt> if \c E | |
| /// matches all \c Bx for \c x in <tt>[0,n)</tt>. | |
| /// | |
| /// When applying <tt>and_\<B0,B1,...Bn\></tt> as a transform with an | |
| /// expression \c e, state \c s and data \c d, it is | |
| /// equivalent to <tt>(B0()(e, s, d),B1()(e, s, d),...Bn()(e, s, d))</tt>. | |
| template<BOOST_PP_ENUM_PARAMS(BOOST_PROTO_MAX_LOGICAL_ARITY, typename G)> | |
| struct and_ : transform<and_<BOOST_PP_ENUM_PARAMS(BOOST_PROTO_MAX_LOGICAL_ARITY, G)> > | |
| { | |
| typedef and_ proto_grammar; | |
| template<typename Expr, typename State, typename Data> | |
| struct impl | |
| : detail::_and_impl<and_, Expr, State, Data> | |
| {}; | |
| }; | |
| /// \brief For matching one of a set of alternate grammars, which | |
| /// are looked up based on an expression's tag type. When used as a | |
| /// transform, \c switch_\<\> applies the transform associated with | |
| /// the grammar that matches the expression. | |
| /// | |
| /// \note \c switch_\<\> is functionally identical to \c or_\<\> but | |
| /// is often more efficient. It does a fast, O(1) lookup based on an | |
| /// expression's tag type to find a sub-grammar that may potentially | |
| /// match the expression. | |
| /// | |
| /// An expression type \c E matches <tt>switch_\<C\></tt> if \c E | |
| /// matches <tt>C::case_\<E::proto_tag\></tt>. | |
| /// | |
| /// When applying <tt>switch_\<C\></tt> as a transform with an | |
| /// expression \c e of type \c E, state \c s and data \c d, it is | |
| /// equivalent to <tt>C::case_\<E::proto_tag\>()(e, s, d)</tt>. | |
| template<typename Cases> | |
| struct switch_ : transform<switch_<Cases> > | |
| { | |
| typedef switch_ proto_grammar; | |
| /// \param e An expression | |
| /// \param s The current state | |
| /// \param d A data of arbitrary type | |
| /// \pre <tt>matches\<Expr,switch_\>::value</tt> is \c true. | |
| /// \return <tt>which()(e, s, d)</tt>, where <tt>which</tt> is | |
| /// <tt>Cases::case_<typename Expr::proto_tag></tt> | |
| template<typename Expr, typename State, typename Data> | |
| struct impl | |
| : Cases::template case_<typename Expr::proto_tag>::template impl<Expr, State, Data> | |
| {}; | |
| template<typename Expr, typename State, typename Data> | |
| struct impl<Expr &, State, Data> | |
| : Cases::template case_<typename Expr::proto_tag>::template impl<Expr &, State, Data> | |
| {}; | |
| }; | |
| /// \brief For forcing exact matches of terminal types. | |
| /// | |
| /// By default, matching terminals ignores references and | |
| /// cv-qualifiers. For instance, a terminal expression of | |
| /// type <tt>terminal\<int const &\>::type</tt> will match | |
| /// the grammar <tt>terminal\<int\></tt>. If that is not | |
| /// desired, you can force an exact match with | |
| /// <tt>terminal\<exact\<int\> \></tt>. This will only | |
| /// match integer terminals where the terminal is held by | |
| /// value. | |
| template<typename T> | |
| struct exact | |
| {}; | |
| /// \brief For matching terminals that are convertible to | |
| /// a type. | |
| /// | |
| /// Use \c convertible_to\<\> to match a terminal that is | |
| /// convertible to some type. For example, the grammar | |
| /// <tt>terminal\<convertible_to\<int\> \></tt> will match | |
| /// any terminal whose argument is convertible to an integer. | |
| /// | |
| /// \note The trait \c is_convertible\<\> from Boost.Type_traits | |
| /// is used to determinal convertibility. | |
| template<typename T> | |
| struct convertible_to | |
| {}; | |
| /// \brief For matching a Grammar to a variable number of | |
| /// sub-expressions. | |
| /// | |
| /// An expression type <tt>expr\<AT, listN\<A0,...An,U0,...Um\> \></tt> | |
| /// matches a grammar <tt>expr\<BT, listM\<B0,...Bn,vararg\<V\> \> \></tt> | |
| /// if \c BT is \c _ or \c AT, and if \c Ax matches \c Bx | |
| /// for each \c x in <tt>[0,n)</tt> and if \c Ux matches \c V | |
| /// for each \c x in <tt>[0,m)</tt>. | |
| /// | |
| /// For example: | |
| /// | |
| /// \code | |
| /// // Match any function call expression, irregardless | |
| /// // of the number of function arguments: | |
| /// struct Function | |
| /// : function< vararg<_> > | |
| /// {}; | |
| /// \endcode | |
| /// | |
| /// When used as a transform, <tt>vararg\<G\></tt> applies | |
| /// <tt>G</tt>'s transform. | |
| template<typename Grammar> | |
| struct vararg | |
| : Grammar | |
| { | |
| /// INTERNAL ONLY | |
| typedef void proto_is_vararg_; | |
| }; | |
| /// INTERNAL ONLY | |
| /// | |
| template<BOOST_PP_ENUM_PARAMS(BOOST_PROTO_MAX_LOGICAL_ARITY, typename G)> | |
| struct is_callable<or_<BOOST_PP_ENUM_PARAMS(BOOST_PROTO_MAX_LOGICAL_ARITY, G)> > | |
| : mpl::true_ | |
| {}; | |
| /// INTERNAL ONLY | |
| /// | |
| template<BOOST_PP_ENUM_PARAMS(BOOST_PROTO_MAX_LOGICAL_ARITY, typename G)> | |
| struct is_callable<and_<BOOST_PP_ENUM_PARAMS(BOOST_PROTO_MAX_LOGICAL_ARITY, G)> > | |
| : mpl::true_ | |
| {}; | |
| /// INTERNAL ONLY | |
| /// | |
| template<typename Grammar> | |
| struct is_callable<not_<Grammar> > | |
| : mpl::true_ | |
| {}; | |
| /// INTERNAL ONLY | |
| /// | |
| template<typename If, typename Then, typename Else> | |
| struct is_callable<if_<If, Then, Else> > | |
| : mpl::true_ | |
| {}; | |
| /// INTERNAL ONLY | |
| /// | |
| template<typename Grammar> | |
| struct is_callable<vararg<Grammar> > | |
| : mpl::true_ | |
| {}; | |
| /// INTERNAL ONLY | |
| /// | |
| template<typename Cases> | |
| struct is_callable<switch_<Cases> > | |
| : mpl::true_ | |
| {}; | |
| }} | |
| #if defined(_MSC_VER) && (_MSC_VER >= 1020) | |
| # pragma warning(pop) | |
| #endif | |
| #endif | |
| #elif BOOST_PP_ITERATION_FLAGS() == 1 | |
| #define N BOOST_PP_ITERATION() | |
| // Assymetry here between the handling of and_N and or_N because | |
| // and_N is used by lambda_matches up to BOOST_PROTO_MAX_ARITY, | |
| // regardless of how low BOOST_PROTO_MAX_LOGICAL_ARITY is. | |
| template<bool B, BOOST_PP_ENUM_PARAMS(BOOST_PP_DEC(N), typename P)> | |
| struct BOOST_PP_CAT(and_, N) | |
| #if 2 == N | |
| : mpl::bool_<P0::value> | |
| {}; | |
| #else | |
| : BOOST_PP_CAT(and_, BOOST_PP_DEC(N))< | |
| P0::value BOOST_PP_COMMA_IF(BOOST_PP_SUB(N,2)) | |
| BOOST_PP_ENUM_SHIFTED_PARAMS(BOOST_PP_DEC(N), P) | |
| > | |
| {}; | |
| #endif | |
| template<BOOST_PP_ENUM_PARAMS(BOOST_PP_DEC(N), typename P)> | |
| struct BOOST_PP_CAT(and_, N)<false, BOOST_PP_ENUM_PARAMS(BOOST_PP_DEC(N), P)> | |
| : mpl::false_ | |
| {}; | |
| #if N <= BOOST_PROTO_MAX_LOGICAL_ARITY | |
| template<BOOST_PP_ENUM_PARAMS(N, typename G), typename Expr, typename State, typename Data> | |
| struct _and_impl<proto::and_<BOOST_PP_ENUM_PARAMS(N, G)>, Expr, State, Data> | |
| : proto::transform_impl<Expr, State, Data> | |
| { | |
| #define M0(Z, N, DATA) \ | |
| typedef \ | |
| typename proto::when<proto::_, BOOST_PP_CAT(G, N)> \ | |
| ::template impl<Expr, State, Data> \ | |
| BOOST_PP_CAT(Gimpl, N); \ | |
| /**/ | |
| BOOST_PP_REPEAT(N, M0, ~) | |
| #undef M0 | |
| typedef typename BOOST_PP_CAT(Gimpl, BOOST_PP_DEC(N))::result_type result_type; | |
| result_type operator()( | |
| typename _and_impl::expr_param e | |
| , typename _and_impl::state_param s | |
| , typename _and_impl::data_param d | |
| ) const | |
| { | |
| // Fix: jfalcou - 12/29/2010 | |
| // Avoid the use of comma operator here so as not to find Proto's | |
| // by accident. | |
| // expands to G0()(e,s,d); G1()(e,s,d); ... G{N-1}()(e,s,d); | |
| #define M0(Z,N,DATA) BOOST_PP_CAT(Gimpl,N)()(e,s,d); | |
| BOOST_PP_REPEAT(BOOST_PP_DEC(N),M0,~) | |
| return BOOST_PP_CAT(Gimpl,BOOST_PP_DEC(N))()(e,s,d); | |
| #undef M0 | |
| } | |
| }; | |
| template<bool B, typename Expr, typename BasicExpr, BOOST_PP_ENUM_PARAMS(N, typename G)> | |
| struct BOOST_PP_CAT(or_, N) | |
| #if 2 == N | |
| : mpl::bool_<matches_<Expr, BasicExpr, typename G1::proto_grammar>::value> | |
| { | |
| typedef G1 which; | |
| }; | |
| #else | |
| : BOOST_PP_CAT(or_, BOOST_PP_DEC(N))< | |
| matches_<Expr, BasicExpr, typename G1::proto_grammar>::value | |
| , Expr, BasicExpr, BOOST_PP_ENUM_SHIFTED_PARAMS(N, G) | |
| > | |
| {}; | |
| #endif | |
| template<typename Expr, typename BasicExpr BOOST_PP_ENUM_TRAILING_PARAMS(N, typename G)> | |
| struct BOOST_PP_CAT(or_, N)<true, Expr, BasicExpr, BOOST_PP_ENUM_PARAMS(N, G)> | |
| : mpl::true_ | |
| { | |
| typedef G0 which; | |
| }; | |
| // handle proto::or_ | |
| template<typename Expr, typename BasicExpr BOOST_PP_ENUM_TRAILING_PARAMS(N, typename G)> | |
| struct matches_<Expr, BasicExpr, proto::or_<BOOST_PP_ENUM_PARAMS(N, G)> > | |
| : BOOST_PP_CAT(or_, N)< | |
| matches_<Expr, BasicExpr, typename G0::proto_grammar>::value, | |
| Expr, BasicExpr BOOST_PP_ENUM_TRAILING_PARAMS(N, G) | |
| > | |
| {}; | |
| // handle proto::and_ | |
| template<typename Expr, typename BasicExpr, BOOST_PP_ENUM_PARAMS(N, typename G)> | |
| struct matches_<Expr, BasicExpr, proto::and_<BOOST_PP_ENUM_PARAMS(N, G)> > | |
| : detail::BOOST_PP_CAT(and_, N)< | |
| BOOST_PROTO_DEFINE_MATCHES(~, 0, ~)::value, | |
| BOOST_PP_ENUM_SHIFTED(N, BOOST_PROTO_DEFINE_MATCHES, ~) | |
| > | |
| {}; | |
| #endif | |
| #undef N | |
| #elif BOOST_PP_ITERATION_FLAGS() == 2 | |
| #define N BOOST_PP_ITERATION() | |
| template<typename Args, typename Back, long To> | |
| struct vararg_matches_impl<Args, Back, N, To> | |
| : and_2< | |
| matches_< | |
| typename detail::expr_traits<typename Args::BOOST_PP_CAT(child, BOOST_PP_DEC(N))>::value_type::proto_derived_expr | |
| , typename detail::expr_traits<typename Args::BOOST_PP_CAT(child, BOOST_PP_DEC(N))>::value_type::proto_grammar | |
| , Back | |
| >::value | |
| , vararg_matches_impl<Args, Back, N + 1, To> | |
| > | |
| {}; | |
| template<typename Args, typename Back> | |
| struct vararg_matches_impl<Args, Back, N, N> | |
| : matches_< | |
| typename detail::expr_traits<typename Args::BOOST_PP_CAT(child, BOOST_PP_DEC(N))>::value_type::proto_derived_expr | |
| , typename detail::expr_traits<typename Args::BOOST_PP_CAT(child, BOOST_PP_DEC(N))>::value_type::proto_grammar | |
| , Back | |
| > | |
| {}; | |
| template< | |
| template<BOOST_PP_ENUM_PARAMS(N, typename BOOST_PP_INTERCEPT)> class T | |
| BOOST_PP_ENUM_TRAILING_PARAMS(N, typename Expr) | |
| BOOST_PP_ENUM_TRAILING_PARAMS(N, typename Grammar) | |
| > | |
| struct lambda_matches< | |
| T<BOOST_PP_ENUM_PARAMS(N, Expr)> | |
| , T<BOOST_PP_ENUM_PARAMS(N, Grammar)> | |
| BOOST_MPL_AUX_LAMBDA_ARITY_PARAM(N) | |
| > | |
| : BOOST_PP_CAT(and_, N)< | |
| BOOST_PROTO_DEFINE_LAMBDA_MATCHES(~, 0, ~)::value, | |
| BOOST_PP_ENUM_SHIFTED(N, BOOST_PROTO_DEFINE_LAMBDA_MATCHES, ~) | |
| > | |
| {}; | |
| template<typename Expr, typename Tag, typename Args1, typename Args2> | |
| struct matches_< Expr, proto::basic_expr<Tag, Args1, N>, proto::basic_expr<Tag, Args2, N> > | |
| : BOOST_PP_CAT(and_, N)< | |
| BOOST_PROTO_MATCHES_N_FUN(~, 0, ~)::value, | |
| BOOST_PP_ENUM_SHIFTED(N, BOOST_PROTO_MATCHES_N_FUN, ~) | |
| > | |
| {}; | |
| template<typename Expr, typename Tag, typename Args1, typename Args2> | |
| struct matches_< Expr, proto::basic_expr<Tag, Args1, N>, proto::basic_expr<proto::_, Args2, N> > | |
| : BOOST_PP_CAT(and_, N)< | |
| BOOST_PROTO_MATCHES_N_FUN(~, 0, ~)::value, | |
| BOOST_PP_ENUM_SHIFTED(N, BOOST_PROTO_MATCHES_N_FUN, ~) | |
| > | |
| {}; | |
| #undef N | |
| #endif | |