[Boost-commit] svn:boost r45318 - branches/proto/v4/boost/proto

From: eric_at_[hidden]
Date: 2008-05-13 02:08:21

Author: eric_niebler
Date: 2008-05-13 02:08:20 EDT (Tue, 13 May 2008)
New Revision: 45318
URL: http://svn.boost.org/trac/boost/changeset/45318

Log:
experimental support for virtual data members of extension classes (e.g., the else_ in if_(foo)[bar].else_[baz])
Text files modified: 
   branches/proto/v4/boost/proto/extends.hpp   |    74 ++++++++++++++++++++++++++++++++++++++++
   branches/proto/v4/boost/proto/proto_fwd.hpp |     5 ++                                      
   branches/proto/v4/boost/proto/tags.hpp      |     3 +                                       
   branches/proto/v4/boost/proto/traits.hpp    |    11 +++++                                   
   4 files changed, 93 insertions(+), 0 deletions(-)

Modified: branches/proto/v4/boost/proto/extends.hpp
==============================================================================
--- branches/proto/v4/boost/proto/extends.hpp	(original)
+++ branches/proto/v4/boost/proto/extends.hpp	2008-05-13 02:08:20 EDT (Tue, 13 May 2008)
@@ -31,6 +31,19 @@
 
 namespace boost { namespace proto
 {
+    #ifdef __GNUC__
+    /// INTERNAL ONLY
+    ///
+    # define BOOST_PROTO_ADDROF(x) ((char const volatile*)boost::addressof(x))
+    /// INTERNAL ONLY
+    ///
+    # define BOOST_PROTO_OFFSETOF(s,m) (BOOST_PROTO_ADDROF((((s *)this)->m)) - BOOST_PROTO_ADDROF(*((s *)this)))
+    #else
+    /// INTERNAL ONLY
+    ///
+    # define BOOST_PROTO_OFFSETOF offsetof
+    #endif
+
     /// INTERNAL ONLY
     ///
     #define BOOST_PROTO_CONST0
@@ -455,6 +468,67 @@
     #include BOOST_PP_LOCAL_ITERATE()
     };
 
+    /// INTERNAL ONLY
+    ///
+    template<typename This, typename Fun, typename Domain>
+    struct virtual_member
+    {
+        typedef
+            expr<tag::member, list2<This &, expr<tag::terminal, term<Fun> > const &> >
+        proto_base_expr;
+        typedef Domain proto_domain;
+        typedef virtual_member<This, Fun, Domain> proto_derived_expr;
+        typedef typename proto_base_expr::proto_tag proto_tag;
+        typedef typename proto_base_expr::proto_args proto_args;
+        typedef typename proto_base_expr::proto_arity proto_arity;
+        typedef typename proto_base_expr::address_of_hack_type_ proto_address_of_hack_type_;
+        typedef void proto_is_expr_;
+        BOOST_PROTO_FUSION_DEFINE_TAG(boost::proto::tag::proto_expr)
+        BOOST_PP_REPEAT(BOOST_PROTO_MAX_ARITY, BOOST_PROTO_EXTENDS_CHILD, ~)
+        typedef void proto_is_aggregate_;
+
+        BOOST_PROTO_EXTENDS_ASSIGN()
+        BOOST_PROTO_EXTENDS_SUBSCRIPT()
+        BOOST_PROTO_EXTENDS_FUNCTION()
+
+        proto_base_expr const proto_base() const
+        {
+            proto_base_expr that = {this->child0(), this->child1()};
+            return that;
+        }
+
+        proto_child0 child0() const
+        {
+            return *(This *)((char *)this - BOOST_PROTO_OFFSETOF(This, proto_member_union_start_));
+        }
+
+        proto_child1 child1() const
+        {
+            static expr<tag::terminal, term<Fun> > const that = {Fun()};
+            return that;
+        }
+    };
+
+    /// INTERNAL ONLY
+    ///
+    #define BOOST_PROTO_DECLARE_MEMBER(R, DATA, ELEM)                                               \
+        boost::proto::exprns_::virtual_member<                                                      \
+            proto_derived_expr                                                                      \
+          , BOOST_PP_TUPLE_ELEM(2, 0, ELEM)                                                         \
+          , proto_domain                                                                            \
+        > BOOST_PP_TUPLE_ELEM(2, 1, ELEM);                                                          \
+        /**/
+
+    /// \brief For declaring virtual data members in an extension class.
+    ///
+    #define BOOST_PROTO_DECLARE_MEMBERS(SEQ)                                                        \
+        union                                                                                       \
+        {                                                                                           \
+            char proto_member_union_start_;                                                         \
+            BOOST_PP_SEQ_FOR_EACH(BOOST_PROTO_DECLARE_MEMBER, ~, SEQ)                               \
+        };                                                                                          \
+        /**/
+
     BOOST_PROTO_END_ADL_NAMESPACE(exprns_)
 
 }}

Modified: branches/proto/v4/boost/proto/proto_fwd.hpp
==============================================================================
--- branches/proto/v4/boost/proto/proto_fwd.hpp	(original)
+++ branches/proto/v4/boost/proto/proto_fwd.hpp	2008-05-13 02:08:20 EDT (Tue, 13 May 2008)
@@ -227,6 +227,7 @@
         struct bitwise_or_assign;
         struct bitwise_xor_assign;
         struct subscript;
+        struct member;
         struct if_else_;
         struct function;
 
@@ -301,6 +302,9 @@
         >
         struct extends;
 
+        template<typename This, typename Fun, typename Domain>
+        struct virtual_member;
+        
         struct is_proto_expr;
     BOOST_PROTO_END_ADL_NAMESPACE(exprns_)
     ////////////////////////////////////////////////////////////////////////////////////////////////
@@ -541,6 +545,7 @@
         template<typename T, typename U> struct bitwise_or_assign;
         template<typename T, typename U> struct bitwise_xor_assign;
         template<typename T, typename U> struct subscript;
+        template<typename T, typename U> struct member;
         template<typename T, typename U, typename V> struct if_else_;
 
         template<BOOST_PP_ENUM_PARAMS_WITH_A_DEFAULT(BOOST_PROTO_MAX_ARITY, typename A, void), typename Dummy = void>

Modified: branches/proto/v4/boost/proto/tags.hpp
==============================================================================
--- branches/proto/v4/boost/proto/tags.hpp	(original)
+++ branches/proto/v4/boost/proto/tags.hpp	2008-05-13 02:08:20 EDT (Tue, 13 May 2008)
@@ -145,6 +145,9 @@
     /// Tag type for the binary subscript operator.
     struct subscript {};
 
+    /// Tag type for the binary virtual data members.
+    struct member {};
+
     /// Tag type for the ternary ?: conditional operator.
     struct if_else_ {};
 

Modified: branches/proto/v4/boost/proto/traits.hpp
==============================================================================
--- branches/proto/v4/boost/proto/traits.hpp	(original)
+++ branches/proto/v4/boost/proto/traits.hpp	2008-05-13 02:08:20 EDT (Tue, 13 May 2008)
@@ -1570,6 +1570,17 @@
                 typedef U proto_child1;
             };
 
+            /// \brief A grammar element for matching virtual data members.
+            ///
+            template<typename T, typename U>
+            struct member
+            {
+                typedef expr<tag::member, list2<T, U> > type;
+                typedef type proto_base_expr;
+
+                // TODO pass-through transform?
+            };
+
         } // namespace op
 
     #define BOOST_PROTO_CHILD(Z, N, DATA)                                                           \