471 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
		
		
			
		
	
	
			471 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
|   | ///////////////////////////////////////////////////////////////////////////////
 | ||
|  | /// \file generate.hpp
 | ||
|  | /// Contains definition of generate\<\> class template, which end users can
 | ||
|  | /// specialize for generating domain-specific expression wrappers.
 | ||
|  | //
 | ||
|  | //  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_GENERATE_HPP_EAN_02_13_2007
 | ||
|  | #define BOOST_PROTO_GENERATE_HPP_EAN_02_13_2007
 | ||
|  | 
 | ||
|  | #include <boost/config.hpp>
 | ||
|  | #include <boost/version.hpp>
 | ||
|  | #include <boost/preprocessor/cat.hpp>
 | ||
|  | #include <boost/preprocessor/iteration/iterate.hpp>
 | ||
|  | #include <boost/preprocessor/facilities/intercept.hpp>
 | ||
|  | #include <boost/preprocessor/repetition/enum_params.hpp>
 | ||
|  | #include <boost/preprocessor/repetition/enum_binary_params.hpp>
 | ||
|  | #include <boost/preprocessor/repetition/enum_trailing_params.hpp>
 | ||
|  | #include <boost/mpl/bool.hpp>
 | ||
|  | #include <boost/utility/enable_if.hpp>
 | ||
|  | #include <boost/utility/result_of.hpp>
 | ||
|  | #include <boost/proto/proto_fwd.hpp>
 | ||
|  | #include <boost/proto/args.hpp>
 | ||
|  | 
 | ||
|  | #if defined(_MSC_VER)
 | ||
|  | # pragma warning(push)
 | ||
|  | # pragma warning(disable : 4714) // function 'xxx' marked as __forceinline not inlined
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | namespace boost { namespace proto | ||
|  | { | ||
|  | 
 | ||
|  |     namespace detail | ||
|  |     { | ||
|  |         template<typename Expr> | ||
|  |         struct by_value_generator_; | ||
|  | 
 | ||
|  |         template<typename Tag, typename Arg> | ||
|  |         struct by_value_generator_<proto::expr<Tag, term<Arg>, 0> > | ||
|  |         { | ||
|  |             typedef | ||
|  |                 proto::expr< | ||
|  |                     Tag | ||
|  |                   , term<typename detail::term_traits<Arg>::value_type> | ||
|  |                   , 0 | ||
|  |                 > | ||
|  |             type; | ||
|  | 
 | ||
|  |             BOOST_FORCEINLINE | ||
|  |             static type const call(proto::expr<Tag, term<Arg>, 0> const &e) | ||
|  |             { | ||
|  |                 type that = {e.child0}; | ||
|  |                 return that; | ||
|  |             } | ||
|  |         }; | ||
|  | 
 | ||
|  |         template<typename Tag, typename Arg> | ||
|  |         struct by_value_generator_<proto::basic_expr<Tag, term<Arg>, 0> > | ||
|  |         { | ||
|  |             typedef | ||
|  |                 proto::basic_expr< | ||
|  |                     Tag | ||
|  |                   , term<typename detail::term_traits<Arg>::value_type> | ||
|  |                   , 0 | ||
|  |                 > | ||
|  |             type; | ||
|  | 
 | ||
|  |             BOOST_FORCEINLINE | ||
|  |             static type const call(proto::basic_expr<Tag, term<Arg>, 0> const &e) | ||
|  |             { | ||
|  |                 type that = {e.child0}; | ||
|  |                 return that; | ||
|  |             } | ||
|  |         }; | ||
|  | 
 | ||
|  |         // Include the other specializations of by_value_generator_
 | ||
|  |         #include <boost/proto/detail/generate_by_value.hpp>
 | ||
|  |     } | ||
|  | 
 | ||
|  |     /// \brief Annotate a generator to indicate that it would
 | ||
|  |     /// prefer to be passed instances of \c proto::basic_expr\<\> rather
 | ||
|  |     /// than \c proto::expr\<\>. <tt>use_basic_expr\<Generator\></tt> is
 | ||
|  |     /// itself a generator.
 | ||
|  |     ///
 | ||
|  |     template<typename Generator> | ||
|  |     struct use_basic_expr | ||
|  |       : Generator | ||
|  |     { | ||
|  |         BOOST_PROTO_USE_BASIC_EXPR() | ||
|  |     }; | ||
|  | 
 | ||
|  |     /// \brief A simple generator that passes an expression
 | ||
|  |     /// through unchanged.
 | ||
|  |     ///
 | ||
|  |     /// Generators are intended for use as the first template parameter
 | ||
|  |     /// to the \c domain\<\> class template and control if and how
 | ||
|  |     /// expressions within that domain are to be customized.
 | ||
|  |     /// The \c default_generator makes no modifications to the expressions
 | ||
|  |     /// passed to it.
 | ||
|  |     struct default_generator | ||
|  |     { | ||
|  |         BOOST_PROTO_CALLABLE() | ||
|  | 
 | ||
|  |         template<typename Sig> | ||
|  |         struct result; | ||
|  | 
 | ||
|  |         template<typename This, typename Expr> | ||
|  |         struct result<This(Expr)> | ||
|  |         { | ||
|  |             typedef Expr type; | ||
|  |         }; | ||
|  | 
 | ||
|  |         /// \param expr A Proto expression
 | ||
|  |         /// \return expr
 | ||
|  |         template<typename Expr> | ||
|  |         BOOST_FORCEINLINE | ||
|  |         BOOST_PROTO_RETURN_TYPE_STRICT_LOOSE(Expr, Expr const &) | ||
|  |         operator ()(Expr const &e) const | ||
|  |         { | ||
|  |             return e; | ||
|  |         } | ||
|  |     }; | ||
|  | 
 | ||
|  |     /// \brief A simple generator that passes an expression
 | ||
|  |     /// through unchanged and specifies a preference for
 | ||
|  |     /// \c proto::basic_expr\<\> over \c proto::expr\<\>.
 | ||
|  |     ///
 | ||
|  |     /// Generators are intended for use as the first template parameter
 | ||
|  |     /// to the \c domain\<\> class template and control if and how
 | ||
|  |     /// expressions within that domain are to be customized.
 | ||
|  |     /// The \c default_generator makes no modifications to the expressions
 | ||
|  |     /// passed to it.
 | ||
|  |     struct basic_default_generator | ||
|  |       : proto::use_basic_expr<default_generator> | ||
|  |     {}; | ||
|  |      | ||
|  |     /// \brief A generator that wraps expressions passed
 | ||
|  |     /// to it in the specified extension wrapper.
 | ||
|  |     ///
 | ||
|  |     /// Generators are intended for use as the first template parameter
 | ||
|  |     /// to the \c domain\<\> class template and control if and how
 | ||
|  |     /// expressions within that domain are to be customized.
 | ||
|  |     /// \c generator\<\> wraps each expression passed to it in
 | ||
|  |     /// the \c Extends\<\> wrapper.
 | ||
|  |     template<template<typename> class Extends> | ||
|  |     struct generator | ||
|  |     { | ||
|  |         BOOST_PROTO_CALLABLE() | ||
|  |         BOOST_PROTO_USE_BASIC_EXPR() | ||
|  | 
 | ||
|  |         template<typename Sig> | ||
|  |         struct result; | ||
|  | 
 | ||
|  |         template<typename This, typename Expr> | ||
|  |         struct result<This(Expr)> | ||
|  |         { | ||
|  |             typedef Extends<Expr> type; | ||
|  |         }; | ||
|  | 
 | ||
|  |         template<typename This, typename Expr> | ||
|  |         struct result<This(Expr &)> | ||
|  |         { | ||
|  |             typedef Extends<Expr> type; | ||
|  |         }; | ||
|  | 
 | ||
|  |         template<typename This, typename Expr> | ||
|  |         struct result<This(Expr const &)> | ||
|  |         { | ||
|  |             typedef Extends<Expr> type; | ||
|  |         }; | ||
|  | 
 | ||
|  |         /// \param expr A Proto expression
 | ||
|  |         /// \return Extends<Expr>(expr)
 | ||
|  |         template<typename Expr> | ||
|  |         BOOST_FORCEINLINE | ||
|  |         Extends<Expr> operator ()(Expr const &e) const | ||
|  |         { | ||
|  |             return Extends<Expr>(e); | ||
|  |         } | ||
|  |     }; | ||
|  | 
 | ||
|  |     /// \brief A generator that wraps expressions passed
 | ||
|  |     /// to it in the specified extension wrapper and uses
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|  |     /// aggregate initialization for the wrapper.
 | ||
|  |     ///
 | ||
|  |     /// Generators are intended for use as the first template parameter
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|  |     /// to the \c domain\<\> class template and control if and how
 | ||
|  |     /// expressions within that domain are to be customized.
 | ||
|  |     /// \c pod_generator\<\> wraps each expression passed to it in
 | ||
|  |     /// the \c Extends\<\> wrapper, and uses aggregate initialzation
 | ||
|  |     /// for the wrapped object.
 | ||
|  |     template<template<typename> class Extends> | ||
|  |     struct pod_generator | ||
|  |     { | ||
|  |         BOOST_PROTO_CALLABLE() | ||
|  |         BOOST_PROTO_USE_BASIC_EXPR() | ||
|  | 
 | ||
|  |         template<typename Sig> | ||
|  |         struct result; | ||
|  | 
 | ||
|  |         template<typename This, typename Expr> | ||
|  |         struct result<This(Expr)> | ||
|  |         { | ||
|  |             typedef Extends<Expr> type; | ||
|  |         }; | ||
|  | 
 | ||
|  |         template<typename This, typename Expr> | ||
|  |         struct result<This(Expr &)> | ||
|  |         { | ||
|  |             typedef Extends<Expr> type; | ||
|  |         }; | ||
|  | 
 | ||
|  |         template<typename This, typename Expr> | ||
|  |         struct result<This(Expr const &)> | ||
|  |         { | ||
|  |             typedef Extends<Expr> type; | ||
|  |         }; | ||
|  | 
 | ||
|  |         /// \param expr The expression to wrap
 | ||
|  |         /// \return <tt>Extends\<Expr\> that = {expr}; return that;</tt>
 | ||
|  |         template<typename Expr> | ||
|  |         BOOST_FORCEINLINE | ||
|  |         Extends<Expr> operator ()(Expr const &e) const | ||
|  |         { | ||
|  |             Extends<Expr> that = {e}; | ||
|  |             return that; | ||
|  |         } | ||
|  | 
 | ||
|  |         // Work-around for:
 | ||
|  |         // https://connect.microsoft.com/VisualStudio/feedback/details/765449/codegen-stack-corruption-using-runtime-checks-when-aggregate-initializing-struct
 | ||
|  |     #if BOOST_WORKAROUND(BOOST_MSVC, < 1800)
 | ||
|  |         template<typename Class, typename Member> | ||
|  |         BOOST_FORCEINLINE | ||
|  |         Extends<expr<tag::terminal, proto::term<Member Class::*> > > operator ()(expr<tag::terminal, proto::term<Member Class::*> > const &e) const | ||
|  |         { | ||
|  |             Extends<expr<tag::terminal, proto::term<Member Class::*> > > that; | ||
|  |             proto::value(that.proto_expr_) = proto::value(e); | ||
|  |             return that; | ||
|  |         } | ||
|  | 
 | ||
|  |         template<typename Class, typename Member> | ||
|  |         BOOST_FORCEINLINE | ||
|  |         Extends<basic_expr<tag::terminal, proto::term<Member Class::*> > > operator ()(basic_expr<tag::terminal, proto::term<Member Class::*> > const &e) const | ||
|  |         { | ||
|  |             Extends<basic_expr<tag::terminal, proto::term<Member Class::*> > > that; | ||
|  |             proto::value(that.proto_expr_) = proto::value(e); | ||
|  |             return that; | ||
|  |         } | ||
|  |     #endif
 | ||
|  |     }; | ||
|  | 
 | ||
|  |     /// \brief A generator that replaces child nodes held by
 | ||
|  |     /// reference with ones held by value. Use with
 | ||
|  |     /// \c compose_generators to forward that result to another
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|  |     /// generator.
 | ||
|  |     ///
 | ||
|  |     /// Generators are intended for use as the first template parameter
 | ||
|  |     /// to the \c domain\<\> class template and control if and how
 | ||
|  |     /// expressions within that domain are to be customized.
 | ||
|  |     /// \c by_value_generator ensures all child nodes are
 | ||
|  |     /// held by value. This generator is typically composed with a
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|  |     /// second generator for further processing, as
 | ||
|  |     /// <tt>compose_generators\<by_value_generator, MyGenerator\></tt>.
 | ||
|  |     struct by_value_generator | ||
|  |     { | ||
|  |         BOOST_PROTO_CALLABLE() | ||
|  | 
 | ||
|  |         template<typename Sig> | ||
|  |         struct result; | ||
|  | 
 | ||
|  |         template<typename This, typename Expr> | ||
|  |         struct result<This(Expr)> | ||
|  |         { | ||
|  |             typedef | ||
|  |                 typename detail::by_value_generator_<Expr>::type | ||
|  |             type; | ||
|  |         }; | ||
|  | 
 | ||
|  |         template<typename This, typename Expr> | ||
|  |         struct result<This(Expr &)> | ||
|  |         { | ||
|  |             typedef | ||
|  |                 typename detail::by_value_generator_<Expr>::type | ||
|  |             type; | ||
|  |         }; | ||
|  | 
 | ||
|  |         template<typename This, typename Expr> | ||
|  |         struct result<This(Expr const &)> | ||
|  |         { | ||
|  |             typedef | ||
|  |                 typename detail::by_value_generator_<Expr>::type | ||
|  |             type; | ||
|  |         }; | ||
|  | 
 | ||
|  |         /// \param expr The expression to modify.
 | ||
|  |         /// \return <tt>deep_copy(expr)</tt>
 | ||
|  |         template<typename Expr> | ||
|  |         BOOST_FORCEINLINE | ||
|  |         typename result<by_value_generator(Expr)>::type operator ()(Expr const &e) const | ||
|  |         { | ||
|  |             return detail::by_value_generator_<Expr>::call(e); | ||
|  |         } | ||
|  |     }; | ||
|  | 
 | ||
|  |     /// \brief A composite generator that first applies one
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|  |     /// transform to an expression and then forwards the result
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|  |     /// on to another generator for further transformation.
 | ||
|  |     ///
 | ||
|  |     /// Generators are intended for use as the first template parameter
 | ||
|  |     /// to the \c domain\<\> class template and control if and how
 | ||
|  |     /// expressions within that domain are to be customized.
 | ||
|  |     /// \c compose_generators\<\> is a composite generator that first
 | ||
|  |     /// applies one transform to an expression and then forwards the
 | ||
|  |     /// result on to another generator for further transformation.
 | ||
|  |     template<typename First, typename Second> | ||
|  |     struct compose_generators | ||
|  |     { | ||
|  |         BOOST_PROTO_CALLABLE() | ||
|  | 
 | ||
|  |         template<typename Sig> | ||
|  |         struct result; | ||
|  | 
 | ||
|  |         template<typename This, typename Expr> | ||
|  |         struct result<This(Expr)> | ||
|  |         { | ||
|  |             typedef | ||
|  |                 typename Second::template result< | ||
|  |                     Second(typename First::template result<First(Expr)>::type) | ||
|  |                 >::type | ||
|  |             type; | ||
|  |         }; | ||
|  | 
 | ||
|  |         template<typename This, typename Expr> | ||
|  |         struct result<This(Expr &)> | ||
|  |         { | ||
|  |             typedef | ||
|  |                 typename Second::template result< | ||
|  |                     Second(typename First::template result<First(Expr)>::type) | ||
|  |                 >::type | ||
|  |             type; | ||
|  |         }; | ||
|  | 
 | ||
|  |         template<typename This, typename Expr> | ||
|  |         struct result<This(Expr const &)> | ||
|  |         { | ||
|  |             typedef | ||
|  |                 typename Second::template result< | ||
|  |                     Second(typename First::template result<First(Expr)>::type) | ||
|  |                 >::type | ||
|  |             type; | ||
|  |         }; | ||
|  | 
 | ||
|  |         /// \param expr The expression to modify.
 | ||
|  |         /// \return Second()(First()(expr))
 | ||
|  |         template<typename Expr> | ||
|  |         BOOST_FORCEINLINE | ||
|  |         typename result<compose_generators(Expr)>::type operator ()(Expr const &e) const | ||
|  |         { | ||
|  |             return Second()(First()(e)); | ||
|  |         } | ||
|  |     }; | ||
|  | 
 | ||
|  |     /// \brief Tests a generator to see whether it would prefer
 | ||
|  |     /// to be passed instances of \c proto::basic_expr\<\> rather than
 | ||
|  |     /// \c proto::expr\<\>.
 | ||
|  |     ///
 | ||
|  |     template<typename Generator, typename Void> | ||
|  |     struct wants_basic_expr | ||
|  |       : mpl::false_ | ||
|  |     {}; | ||
|  | 
 | ||
|  |     template<typename Generator> | ||
|  |     struct wants_basic_expr<Generator, typename Generator::proto_use_basic_expr_> | ||
|  |       : mpl::true_ | ||
|  |     {}; | ||
|  | 
 | ||
|  |     /// INTERNAL ONLY
 | ||
|  |     template<> | ||
|  |     struct is_callable<default_generator> | ||
|  |       : mpl::true_ | ||
|  |     {}; | ||
|  | 
 | ||
|  |     /// INTERNAL ONLY
 | ||
|  |     template<template<typename> class Extends> | ||
|  |     struct is_callable<generator<Extends> > | ||
|  |       : mpl::true_ | ||
|  |     {}; | ||
|  | 
 | ||
|  |     /// INTERNAL ONLY
 | ||
|  |     template<template<typename> class Extends> | ||
|  |     struct is_callable<pod_generator<Extends> > | ||
|  |       : mpl::true_ | ||
|  |     {}; | ||
|  | 
 | ||
|  |     /// INTERNAL ONLY
 | ||
|  |     template<> | ||
|  |     struct is_callable<by_value_generator> | ||
|  |       : mpl::true_ | ||
|  |     {}; | ||
|  | 
 | ||
|  |     /// INTERNAL ONLY
 | ||
|  |     template<typename First, typename Second> | ||
|  |     struct is_callable<compose_generators<First, Second> > | ||
|  |       : mpl::true_ | ||
|  |     {}; | ||
|  | 
 | ||
|  | }} | ||
|  | 
 | ||
|  | // Specializations of boost::result_of and boost::tr1_result_of to eliminate
 | ||
|  | // some unnecessary template instantiations
 | ||
|  | namespace boost | ||
|  | { | ||
|  |     template<typename Expr> | ||
|  |     struct result_of<proto::default_domain(Expr)> | ||
|  |     { | ||
|  |         typedef Expr type; | ||
|  |     }; | ||
|  | 
 | ||
|  |     template<typename Expr> | ||
|  |     struct result_of<proto::basic_default_domain(Expr)> | ||
|  |     { | ||
|  |         typedef Expr type; | ||
|  |     }; | ||
|  | 
 | ||
|  |     template<typename Expr> | ||
|  |     struct result_of<proto::default_generator(Expr)> | ||
|  |     { | ||
|  |         typedef Expr type; | ||
|  |     }; | ||
|  | 
 | ||
|  |     template<typename Expr> | ||
|  |     struct result_of<proto::basic_default_generator(Expr)> | ||
|  |     { | ||
|  |         typedef Expr type; | ||
|  |     }; | ||
|  | 
 | ||
|  |     #if BOOST_VERSION >= 104400
 | ||
|  |     template<typename Expr> | ||
|  |     struct tr1_result_of<proto::default_domain(Expr)> | ||
|  |     { | ||
|  |         typedef Expr type; | ||
|  |     }; | ||
|  | 
 | ||
|  |     template<typename Expr> | ||
|  |     struct tr1_result_of<proto::basic_default_domain(Expr)> | ||
|  |     { | ||
|  |         typedef Expr type; | ||
|  |     }; | ||
|  | 
 | ||
|  |     template<typename Expr> | ||
|  |     struct tr1_result_of<proto::default_generator(Expr)> | ||
|  |     { | ||
|  |         typedef Expr type; | ||
|  |     }; | ||
|  | 
 | ||
|  |     template<typename Expr> | ||
|  |     struct tr1_result_of<proto::basic_default_generator(Expr)> | ||
|  |     { | ||
|  |         typedef Expr type; | ||
|  |     }; | ||
|  |     #endif
 | ||
|  | } | ||
|  | 
 | ||
|  | #if defined(_MSC_VER)
 | ||
|  | # pragma warning(pop)
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | #endif // BOOST_PROTO_GENERATE_HPP_EAN_02_13_2007
 |