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diff --git a/3rdParty/Boost/src/boost/proto/matches.hpp b/3rdParty/Boost/src/boost/proto/matches.hpp new file mode 100644 index 0000000..38ff962 --- /dev/null +++ b/3rdParty/Boost/src/boost/proto/matches.hpp @@ -0,0 +1,947 @@ +/////////////////////////////////////////////////////////////////////////////// +/// \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/proto/detail/template_arity.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> + +#if defined(_MSC_VER) && (_MSC_VER >= 1020) +# pragma warning(push) +# pragma warning(disable:4305) // 'specialization' : truncation from 'const int' to 'bool' +#endif + +#define BOOST_PROTO_LOGICAL_typename_G BOOST_PP_ENUM_PARAMS(BOOST_PROTO_MAX_LOGICAL_ARITY, typename G) +#define BOOST_PROTO_LOGICAL_G BOOST_PP_ENUM_PARAMS(BOOST_PROTO_MAX_LOGICAL_ARITY, G) + +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_PROTO_TEMPLATE_ARITY_PARAM(long Arity = detail::template_arity<U>::value) + > + struct lambda_matches + : mpl::false_ + {}; + + template<typename T> + struct lambda_matches<T, proto::_ BOOST_PROTO_TEMPLATE_ARITY_PARAM(-1)> + : mpl::true_ + {}; + + template<typename T> + struct lambda_matches<T, T BOOST_PROTO_TEMPLATE_ARITY_PARAM(-1)> + : mpl::true_ + {}; + + template<typename T, std::size_t M, typename U> + struct lambda_matches<T[M], U BOOST_PROTO_TEMPLATE_ARITY_PARAM(-1)> + : array_matches<T[M], U> + {}; + + template<typename T, std::size_t M> + struct lambda_matches<T[M], _ BOOST_PROTO_TEMPLATE_ARITY_PARAM(-1)> + : mpl::true_ + {}; + + template<typename T, std::size_t M> + struct lambda_matches<T[M], T[M] BOOST_PROTO_TEMPLATE_ARITY_PARAM(-1)> + : mpl::true_ + {}; + + template<template<typename> class T, typename Expr0, typename Grammar0> + struct lambda_matches<T<Expr0>, T<Grammar0> BOOST_PROTO_TEMPLATE_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 + > + {}; + + #include <boost/proto/detail/and_n.hpp> + #include <boost/proto/detail/or_n.hpp> + #include <boost/proto/detail/matches_.hpp> + #include <boost/proto/detail/vararg_matches_impl.hpp> + #include <boost/proto/detail/lambda_matches.hpp> + + // 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< + static_cast<bool>( + 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< + static_cast<bool>( + 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, typename Transform> + struct matches_<Expr, proto::basic_expr<Tag, Args, Arity>, switch_<Cases, Transform> > + : matches_< + Expr + , proto::basic_expr<Tag, Args, Arity> + , typename Cases::template case_< + typename when<_,Transform>::template impl<Expr,int,int>::result_type + >::proto_grammar + > + { + typedef + typename Cases::template case_< + typename when<_, Transform>::template impl<Expr, int, int>::result_type + > + which; + }; + + // handle proto::switch_ with the default Transform for specially for better compile times + 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,T\></tt> if + /// \c E matches <tt>C::case_\<boost::result_of\<T(E)\>::type\></tt>. + /// (Note: T defaults to <tt>tag_of\<_\>()</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 + BOOST_PROTO_RETURN_TYPE_STRICT_LOOSE(result_type, typename impl::expr_param) + 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 + BOOST_PROTO_RETURN_TYPE_STRICT_LOOSE(result_type, typename impl::expr_param) + 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< + static_cast<bool>(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_PROTO_LOGICAL_typename_G> + struct or_ : transform<or_<BOOST_PROTO_LOGICAL_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_PROTO_LOGICAL_typename_G> + struct and_ : transform<and_<BOOST_PROTO_LOGICAL_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 some property of an expression. The + /// property on which to dispatch is specified by the \c Transform + /// template parameter, which defaults to <tt>tag_of\<_\>()</tt>. + /// That is, when the \c Trannsform is not specified, the alternate + /// grammar is looked up using the tag type of the current expression. + /// + /// 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 using the + /// result of the specified transform to find a sub-grammar that may + /// potentially match the expression. + /// + /// An expression type \c E matches <tt>switch_\<C,T\></tt> if \c E + /// matches <tt>C::case_\<boost::result_of\<T(E)\>::type\></tt>. + /// + /// When applying <tt>switch_\<C,T\></tt> as a transform with an + /// expression \c e of type \c E, state \c s of type \S and data + /// \c d of type \c D, it is equivalent to + /// <tt>C::case_\<boost::result_of\<T(E,S,D)\>::type\>()(e, s, d)</tt>. + template<typename Cases, typename Transform> + struct switch_ : transform<switch_<Cases, Transform> > + { + typedef switch_ proto_grammar; + + template<typename Expr, typename State, typename Data> + struct impl + : Cases::template case_< + typename when<_, Transform>::template impl<Expr, State, Data>::result_type + >::template impl<Expr, State, Data> + {}; + }; + + /// INTERNAL ONLY (This is merely a compile-time optimization for the common case) + /// + template<typename Cases> + struct switch_<Cases> : transform<switch_<Cases> > + { + typedef switch_ proto_grammar; + + 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_PROTO_LOGICAL_typename_G> + struct is_callable<or_<BOOST_PROTO_LOGICAL_G> > + : mpl::true_ + {}; + + /// INTERNAL ONLY + /// + template<BOOST_PROTO_LOGICAL_typename_G> + struct is_callable<and_<BOOST_PROTO_LOGICAL_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, typename Transform> + struct is_callable<switch_<Cases, Transform> > + : mpl::true_ + {}; + +}} + +#undef BOOST_PROTO_LOGICAL_typename_G +#undef BOOST_PROTO_LOGICAL_G + +#if defined(_MSC_VER) && (_MSC_VER >= 1020) +# pragma warning(pop) +#endif + +#endif |