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Diffstat (limited to '3rdParty/Boost/src/boost/proto/transform/pass_through.hpp')
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diff --git a/3rdParty/Boost/src/boost/proto/transform/pass_through.hpp b/3rdParty/Boost/src/boost/proto/transform/pass_through.hpp new file mode 100644 index 0000000..216097b --- /dev/null +++ b/3rdParty/Boost/src/boost/proto/transform/pass_through.hpp @@ -0,0 +1,204 @@ +#ifndef BOOST_PP_IS_ITERATING + /////////////////////////////////////////////////////////////////////////////// + /// \file pass_through.hpp + /// + /// Definition of the pass_through transform, which is the default transform + /// of all of the expression generator metafunctions such as unary_plus<>, plus<> + /// and nary_expr<>. + // + // 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_TRANSFORM_PASS_THROUGH_HPP_EAN_12_26_2006 + #define BOOST_PROTO_TRANSFORM_PASS_THROUGH_HPP_EAN_12_26_2006 + + #include <boost/preprocessor/cat.hpp> + #include <boost/preprocessor/repetition/enum.hpp> + #include <boost/preprocessor/iteration/iterate.hpp> + #include <boost/mpl/bool.hpp> + #include <boost/type_traits/remove_reference.hpp> + #include <boost/proto/proto_fwd.hpp> + #include <boost/proto/args.hpp> + #include <boost/proto/transform/impl.hpp> + + namespace boost { namespace proto + { + namespace detail + { + template< + typename Grammar + , typename Expr + , typename State + , typename Data + , long Arity = arity_of<Expr>::value + > + struct pass_through_impl + {}; + + #define BOOST_PROTO_DEFINE_TRANSFORM_TYPE(Z, N, DATA) \ + typename Grammar::BOOST_PP_CAT(proto_child, N)::template impl< \ + typename result_of::child_c<Expr, N>::type \ + , State \ + , Data \ + >::result_type \ + /**/ + + #define BOOST_PROTO_DEFINE_TRANSFORM(Z, N, DATA) \ + typename Grammar::BOOST_PP_CAT(proto_child, N)::template impl< \ + typename result_of::child_c<Expr, N>::type \ + , State \ + , Data \ + >()( \ + e.proto_base().BOOST_PP_CAT(child, N), s, d \ + ) \ + /**/ + + #define BOOST_PP_ITERATION_PARAMS_1 (3, (1, BOOST_PROTO_MAX_ARITY, <boost/proto/transform/pass_through.hpp>)) + #include BOOST_PP_ITERATE() + + #undef BOOST_PROTO_DEFINE_TRANSFORM + #undef BOOST_PROTO_DEFINE_TRANSFORM_TYPE + + template<typename Grammar, typename Expr, typename State, typename Data> + struct pass_through_impl<Grammar, Expr, State, Data, 0> + : transform_impl<Expr, State, Data> + { + typedef Expr result_type; + + /// \param e An expression + /// \return \c e + /// \throw nothrow + #ifdef BOOST_PROTO_STRICT_RESULT_OF + result_type + #else + typename pass_through_impl::expr_param + #endif + operator()( + typename pass_through_impl::expr_param e + , typename pass_through_impl::state_param + , typename pass_through_impl::data_param + ) const + { + return e; + } + }; + + } // namespace detail + + /// \brief A PrimitiveTransform that transforms the child expressions + /// of an expression node according to the corresponding children of + /// a Grammar. + /// + /// Given a Grammar such as <tt>plus\<T0, T1\></tt>, an expression type + /// that matches the grammar such as <tt>plus\<E0, E1\>::type</tt>, a + /// state \c S and a data \c V, the result of applying the + /// <tt>pass_through\<plus\<T0, T1\> \></tt> transform is: + /// + /// \code + /// plus< + /// T0::result<T0(E0, S, V)>::type + /// , T1::result<T1(E1, S, V)>::type + /// >::type + /// \endcode + /// + /// The above demonstrates how child transforms and child expressions + /// are applied pairwise, and how the results are reassembled into a new + /// expression node with the same tag type as the original. + /// + /// The explicit use of <tt>pass_through\<\></tt> is not usually needed, + /// since the expression generator metafunctions such as + /// <tt>plus\<\></tt> have <tt>pass_through\<\></tt> as their default + /// transform. So, for instance, these are equivalent: + /// + /// \code + /// // Within a grammar definition, these are equivalent: + /// when< plus<X, Y>, pass_through< plus<X, Y> > > + /// when< plus<X, Y>, plus<X, Y> > + /// when< plus<X, Y> > // because of when<class X, class Y=X> + /// plus<X, Y> // because plus<> is both a + /// // grammar and a transform + /// \endcode + /// + /// For example, consider the following transform that promotes all + /// \c float terminals in an expression to \c double. + /// + /// \code + /// // This transform finds all float terminals in an expression and promotes + /// // them to doubles. + /// struct Promote + /// : or_< + /// when<terminal<float>, terminal<double>::type(_value) > + /// // terminal<>'s default transform is a no-op: + /// , terminal<_> + /// // nary_expr<> has a pass_through<> transform: + /// , nary_expr<_, vararg<Promote> > + /// > + /// {}; + /// \endcode + template<typename Grammar> + struct pass_through + : transform<pass_through<Grammar> > + { + template<typename Expr, typename State, typename Data> + struct impl + : detail::pass_through_impl<Grammar, Expr, State, Data> + {}; + }; + + /// INTERNAL ONLY + /// + template<typename Grammar> + struct is_callable<pass_through<Grammar> > + : mpl::true_ + {}; + + }} // namespace boost::proto + + #endif + +#else + + #define N BOOST_PP_ITERATION() + + template<typename Grammar, typename Expr, typename State, typename Data> + struct pass_through_impl<Grammar, Expr, State, Data, N> + : transform_impl<Expr, State, Data> + { + typedef typename pass_through_impl::expr unref_expr; + + typedef + typename base_expr< + typename unref_expr::proto_domain + , typename unref_expr::proto_tag + , BOOST_PP_CAT(list, N)< + BOOST_PP_ENUM(N, BOOST_PROTO_DEFINE_TRANSFORM_TYPE, ~) + > + >::type + expr_type; + + typedef typename unref_expr::proto_generator proto_generator; + typedef typename BOOST_PROTO_RESULT_OF<proto_generator(expr_type)>::type const result_type; + + result_type const operator ()( + typename pass_through_impl::expr_param e + , typename pass_through_impl::state_param s + , typename pass_through_impl::data_param d + ) const + { + expr_type const that = { + BOOST_PP_ENUM(N, BOOST_PROTO_DEFINE_TRANSFORM, ~) + }; + #if BOOST_WORKAROUND(BOOST_MSVC, BOOST_TESTED_AT(1400)) + // Without this, MSVC complains that "that" is uninitialized, + // and it actually triggers a runtime check in debug mode when + // built with VC8. + &that; + #endif + return proto_generator()(that); + } + }; + + #undef N + +#endif |