comparison DEPENDENCIES/generic/include/boost/proto/domain.hpp @ 16:2665513ce2d3

Add boost headers

+///////////////////////////////////////////////////////////////////////////////
+/// \file domain.hpp
+/// Contains definition of domain\<\> class template and helpers for
+/// defining domains with a generator and a grammar for controlling
+/// operator overloading.
+//
+//  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_DOMAIN_HPP_EAN_02_13_2007
+#define BOOST_PROTO_DOMAIN_HPP_EAN_02_13_2007
+
+#include <boost/ref.hpp>
+#include <boost/type_traits/is_same.hpp>
+#include <boost/proto/proto_fwd.hpp>
+#include <boost/proto/generate.hpp>
+#include <boost/proto/detail/as_expr.hpp>
+#include <boost/proto/detail/deduce_domain.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
+    {
+        struct not_a_generator
+        {};
+
+        struct not_a_grammar
+        {};
+
+        struct not_a_domain
+        {};
+    }
+
+    namespace domainns_
+    {
+        /// \brief For use in defining domain tags to be used
+        /// with \c proto::extends\<\>. A \e Domain associates
+        /// an expression type with a \e Generator, and optionally
+        /// a \e Grammar.
+        ///
+        /// The Generator determines how new expressions in the
+        /// domain are constructed. Typically, a generator wraps
+        /// all new expressions in a wrapper that imparts
+        /// domain-specific behaviors to expressions within its
+        /// domain. (See \c proto::extends\<\>.)
+        ///
+        /// The Grammar determines whether a given expression is
+        /// valid within the domain, and automatically disables
+        /// any operator overloads which would cause an invalid
+        /// expression to be created. By default, the Grammar
+        /// parameter defaults to the wildcard, \c proto::_, which
+        /// makes all expressions valid within the domain.
+        ///
+        /// The Super declares the domain currently being defined
+        /// to be a sub-domain of Super. Expressions in sub-domains
+        /// can be freely combined with expressions in its super-
+        /// domain (and <I>its</I> super-domain, etc.).
+        ///
+        /// Example:
+        /// \code
+        /// template<typename Expr>
+        /// struct MyExpr;
+        ///
+        /// struct MyGrammar
+        ///   : or_< terminal<_>, plus<MyGrammar, MyGrammar> >
+        /// {};
+        ///
+        /// // Define MyDomain, in which all expressions are
+        /// // wrapped in MyExpr<> and only expressions that
+        /// // conform to MyGrammar are allowed.
+        /// struct MyDomain
+        ///   : domain<generator<MyExpr>, MyGrammar>
+        /// {};
+        ///
+        /// // Use MyDomain to define MyExpr
+        /// template<typename Expr>
+        /// struct MyExpr
+        ///   : extends<Expr, MyExpr<Expr>, MyDomain>
+        /// {
+        ///     // ...
+        /// };
+        /// \endcode
+        ///
+        template<
+            typename Generator // = default_generator
+          , typename Grammar   // = proto::_
+          , typename Super     // = no_super_domain
+        >
+        struct domain
+          : Generator
+        {
+            typedef Generator proto_generator;
+            typedef Grammar   proto_grammar;
+            typedef Super     proto_super_domain;
+            typedef domain    proto_base_domain;
+
+            /// INTERNAL ONLY
+            typedef void proto_is_domain_;
+
+            /// \brief A unary MonomorphicFunctionObject that turns objects into Proto
+            /// expression objects in this domain.
+            ///
+            /// The <tt>as_expr\<\></tt> function object turns objects into Proto expressions, if
+            /// they are not already, by making them Proto terminals held by value if
+            /// possible. Objects that are already Proto expressions are left alone.
+            ///
+            /// If <tt>wants_basic_expr\<Generator\>::value</tt> is true, then let \c E be \c basic_expr;
+            /// otherwise, let \t E be \c expr. Given an lvalue \c t of type \c T:
+            ///
+            /// If \c T is not a Proto expression type the resulting terminal is
+            /// calculated as follows:
+            ///
+            ///   If \c T is a function type, an abstract type, or a type derived from
+            ///   \c std::ios_base, let \c A be <tt>T &</tt>.
+            ///   Otherwise, let \c A be the type \c T stripped of cv-qualifiers.
+            ///   Then, the result of applying <tt>as_expr\<T\>()(t)</tt> is
+            ///   <tt>Generator()(E\<tag::terminal, term\<A\> \>::make(t))</tt>.
+            ///
+            /// If \c T is a Proto expression type and its generator type is different from
+            /// \c Generator, the result is <tt>Generator()(t)</tt>.
+            ///
+            /// Otherwise, the result is \c t converted to an (un-const) rvalue.
+            ///
+            template<typename T, typename IsExpr = void, typename Callable = proto::callable>
+            struct as_expr
+              : detail::as_expr<
+                    T
+                  , typename detail::base_generator<Generator>::type
+                  , wants_basic_expr<Generator>::value
+                >
+            {
+                BOOST_PROTO_CALLABLE()
+            };
+
+            /// INTERNAL ONLY
+            ///
+            template<typename T>
+            struct as_expr<T, typename T::proto_is_expr_, proto::callable>
+            {
+                BOOST_PROTO_CALLABLE()
+                typedef typename remove_const<T>::type result_type;
+
+                BOOST_FORCEINLINE
+                result_type operator()(T &e) const
+                {
+                    return e;
+                }
+            };
+
+            /// \brief A unary MonomorphicFunctionObject that turns objects into Proto
+            /// expression objects in this domain.
+            ///
+            /// The <tt>as_child\<\></tt> function object turns objects into Proto expressions, if
+            /// they are not already, by making them Proto terminals held by reference.
+            /// Objects that are already Proto expressions are simply returned by reference.
+            ///
+            /// If <tt>wants_basic_expr\<Generator\>::value</tt> is true, then let \c E be \c basic_expr;
+            /// otherwise, let \t E be \c expr. Given an lvalue \c t of type \c T:
+            ///
+            /// If \c T is not a Proto expression type the resulting terminal is
+            /// <tt>Generator()(E\<tag::terminal, term\<T &\> \>::make(t))</tt>.
+            ///
+            /// If \c T is a Proto expression type and its generator type is different from
+            /// \c Generator, the result is <tt>Generator()(t)</tt>.
+            ///
+            /// Otherwise, the result is the lvalue \c t.
+            ///
+            template<typename T, typename IsExpr = void, typename Callable = proto::callable>
+            struct as_child
+              : detail::as_child<
+                    T
+                  , typename detail::base_generator<Generator>::type
+                  , wants_basic_expr<Generator>::value
+                >
+            {
+                BOOST_PROTO_CALLABLE()
+            };
+
+            /// INTERNAL ONLY
+            ///
+            template<typename T>
+            struct as_child<T, typename T::proto_is_expr_, proto::callable>
+            {
+                BOOST_PROTO_CALLABLE()
+                typedef T &result_type;
+
+                BOOST_FORCEINLINE
+                result_type operator()(T &e) const
+                {
+                    return e;
+                }
+            };
+        };
+
+        /// \brief The domain expressions have by default, if
+        /// \c proto::extends\<\> has not been used to associate
+        /// a domain with an expression.
+        ///
+        struct default_domain
+          : domain<>
+        {};
+
+        /// \brief A domain to use when you prefer the use of
+        /// \c proto::basic_expr\<\> over \c proto::expr\<\>.
+        ///
+        struct basic_default_domain
+          : domain<basic_default_generator>
+        {};
+
+        /// \brief A pseudo-domain for use in functions and
+        /// metafunctions that require a domain parameter. It
+        /// indicates that the domain of the parent node should
+        /// be inferred from the domains of the child nodes.
+        ///
+        /// \attention \c deduce_domain is not itself a valid domain.
+        ///
+        struct deduce_domain
+          : domain<detail::not_a_generator, detail::not_a_grammar, detail::not_a_domain>
+        {};
+
+        /// \brief Given a domain, a tag type and an argument list,
+        /// compute the type of the expression to generate. This is
+        /// either an instance of \c proto::expr\<\> or
+        /// \c proto::basic_expr\<\>.
+        ///
+        template<typename Domain, typename Tag, typename Args, bool WantsBasicExpr>
+        struct base_expr
+        {
+            typedef proto::expr<Tag, Args, Args::arity> type;
+        };
+
+        /// INTERNAL ONLY
+        ///
+        template<typename Domain, typename Tag, typename Args>
+        struct base_expr<Domain, Tag, Args, true>
+        {
+            typedef proto::basic_expr<Tag, Args, Args::arity> type;
+        };
+
+    }
+
+    /// A metafunction that returns \c mpl::true_
+    /// if the type \c T is the type of a Proto domain;
+    /// \c mpl::false_ otherwise. If \c T inherits from
+    /// \c proto::domain\<\>, \c is_domain\<T\> is
+    /// \c mpl::true_.
+    template<typename T, typename Void  /* = void*/>
+    struct is_domain
+      : mpl::false_
+    {};
+
+    /// INTERNAL ONLY
+    ///
+    template<typename T>
+    struct is_domain<T, typename T::proto_is_domain_>
+      : mpl::true_
+    {};
+
+    /// A metafunction that returns the domain of
+    /// a given type. If \c T is a Proto expression
+    /// type, it returns that expression's associated
+    /// domain. If not, it returns
+    /// \c proto::default_domain.
+    template<typename T, typename Void /* = void*/>
+    struct domain_of
+    {
+        typedef default_domain type;
+    };
+
+    /// INTERNAL ONLY
+    ///
+    template<typename T>
+    struct domain_of<T, typename T::proto_is_expr_>
+    {
+        typedef typename T::proto_domain type;
+    };
+
+    /// INTERNAL ONLY
+    ///
+    template<typename T>
+    struct domain_of<T &, void>
+    {
+        typedef typename domain_of<T>::type type;
+    };
+
+    /// INTERNAL ONLY
+    ///
+    template<typename T>
+    struct domain_of<boost::reference_wrapper<T>, void>
+    {
+        typedef typename domain_of<T>::type type;
+    };
+
+    /// INTERNAL ONLY
+    ///
+    template<typename T>
+    struct domain_of<boost::reference_wrapper<T> const, void>
+    {
+        typedef typename domain_of<T>::type type;
+    };
+
+    /// A metafunction that returns \c mpl::true_
+    /// if the type \c SubDomain is a sub-domain of
+    /// \c SuperDomain; \c mpl::false_ otherwise.
+    template<typename SubDomain, typename SuperDomain>
+    struct is_sub_domain_of
+      : is_sub_domain_of<typename SubDomain::proto_super_domain, SuperDomain>
+    {};
+
+    /// INTERNAL ONLY
+    ///
+    template<typename SuperDomain>
+    struct is_sub_domain_of<proto::no_super_domain, SuperDomain>
+      : mpl::false_
+    {};
+
+    /// INTERNAL ONLY
+    ///
+    template<typename SuperDomain>
+    struct is_sub_domain_of<SuperDomain, SuperDomain>
+      : mpl::true_
+    {};
+
+}}
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma warning(pop)
+#endif
+
+#endif