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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..9c43008 --- /dev/null +++ b/3rdParty/Boost/src/boost/proto/transform/pass_through.hpp @@ -0,0 +1,145 @@ +/////////////////////////////////////////////////////////////////////////////// +/// \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/mpl/if.hpp> +#include <boost/type_traits/is_same.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> +#include <boost/proto/detail/ignore_unused.hpp> + +#if defined(_MSC_VER) && (_MSC_VER >= 1020) +# pragma warning(push) +# pragma warning(disable : 4714) // function 'xxx' marked as __forceinline not inlined +#endif + +namespace boost { namespace proto +{ + namespace detail + { + template< + typename Grammar + , typename Domain + , typename Expr + , typename State + , typename Data + , long Arity = arity_of<Expr>::value + > + struct pass_through_impl + {}; + + #include <boost/proto/transform/detail/pass_through_impl.hpp> + + template<typename Grammar, typename Domain, typename Expr, typename State, typename Data> + struct pass_through_impl<Grammar, Domain, Expr, State, Data, 0> + : transform_impl<Expr, State, Data> + { + typedef Expr result_type; + + /// \param e An expression + /// \return \c e + /// \throw nothrow + BOOST_FORCEINLINE + BOOST_PROTO_RETURN_TYPE_STRICT_LOOSE(result_type, typename pass_through_impl::expr_param) + 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, typename Domain /* = deduce_domain*/> + struct pass_through + : transform<pass_through<Grammar, Domain> > + { + template<typename Expr, typename State, typename Data> + struct impl + : detail::pass_through_impl<Grammar, Domain, Expr, State, Data> + {}; + }; + + /// INTERNAL ONLY + /// + template<typename Grammar, typename Domain> + struct is_callable<pass_through<Grammar, Domain> > + : mpl::true_ + {}; + +}} // namespace boost::proto + +#if defined(_MSC_VER) && (_MSC_VER >= 1020) +# pragma warning(pop) +#endif + +#endif |