[Boost-commit] svn:boost r40310 - in trunk/boost/xpressive: detail/core/matcher proto

From: eric_at_[hidden]
Date: 2007-10-22 20:40:17

Author: eric_niebler
Date: 2007-10-22 20:40:16 EDT (Mon, 22 Oct 2007)
New Revision: 40310
URL: http://svn.boost.org/trac/boost/changeset/40310

Log:
fix problem with ->* rewrite in actions, add x->*y as alias for y(x)
Text files modified: 
   trunk/boost/xpressive/detail/core/matcher/action_matcher.hpp |    54 +++++++++++++++++++++++++++++++-------- 
   trunk/boost/xpressive/proto/fusion.hpp                       |     9 ++----                                  
   2 files changed, 45 insertions(+), 18 deletions(-)

Modified: trunk/boost/xpressive/detail/core/matcher/action_matcher.hpp
==============================================================================
--- trunk/boost/xpressive/detail/core/matcher/action_matcher.hpp	(original)
+++ trunk/boost/xpressive/detail/core/matcher/action_matcher.hpp	2007-10-22 20:40:16 EDT (Mon, 22 Oct 2007)
@@ -40,24 +40,28 @@
 {
 
     #if BOOST_VERSION >= 103500
+    struct DataMember
+      : proto::mem_ptr<proto::_, proto::terminal<proto::_> >
+    {};
+
+    template<typename Expr, long N>
+    struct child_
+      : remove_reference<typename mpl::if_<
+            is_const<Expr>
+          , typename proto::result_of::arg_c<Expr, N>::const_reference
+          , typename proto::result_of::arg_c<Expr, N>::reference
+        >::type>
+    {};
+
     ///////////////////////////////////////////////////////////////////////////////
     // mem_ptr_eval
     //  Rewrites expressions of the form x->*foo(a) into foo(x, a) and then
     //  evaluates them.
-    template<typename Expr, typename Context>
+    template<typename Expr, typename Context, bool IsDataMember = proto::matches<Expr, DataMember>::value>
     struct mem_ptr_eval
     {
-        typedef typename remove_reference<typename mpl::if_<
-            is_const<Expr>
-          , typename proto::result_of::right<Expr>::const_reference
-          , typename proto::result_of::right<Expr>::reference
-        >::type>::type right_type;
-
-        typedef typename remove_reference<typename mpl::if_<
-            is_const<Expr>
-          , typename proto::result_of::left<Expr>::const_reference
-          , typename proto::result_of::left<Expr>::reference
-        >::type>::type left_type;
+        typedef typename child_<Expr, 0>::type left_type;
+        typedef typename child_<Expr, 1>::type right_type;
 
         typedef
             typename proto::result_of::arg<
@@ -90,6 +94,32 @@
             );
         }
     };
+
+    ///////////////////////////////////////////////////////////////////////////////
+    // mem_ptr_eval
+    //  Rewrites expressions of the form x->*foo into foo(x) and then
+    //  evaluates them.
+    template<typename Expr, typename Context>
+    struct mem_ptr_eval<Expr, Context, true>
+    {
+        typedef typename child_<Expr, 0>::type left_type;
+        typedef typename child_<Expr, 1>::type right_type;
+
+        typedef
+            typename proto::result_of::arg<right_type>::type
+        function_type;
+
+        typedef typename boost::result_of<
+            function_type(typename proto::result_of::eval<left_type, Context>::type)
+        >::type result_type;
+
+        result_type operator()(Expr &expr, Context &ctx) const
+        {
+            return proto::arg(proto::right(expr))(
+                proto::eval(proto::left(expr), ctx)
+            );
+        }
+    };
     #endif
 
     struct attr_with_default_tag

Modified: trunk/boost/xpressive/proto/fusion.hpp
==============================================================================
--- trunk/boost/xpressive/proto/fusion.hpp	(original)
+++ trunk/boost/xpressive/proto/fusion.hpp	2007-10-22 20:40:16 EDT (Mon, 22 Oct 2007)
@@ -86,14 +86,11 @@
 
         template<typename This, typename Expr>
         struct result<This(Expr)>
-        {
-            typedef
-                typename Context::template eval<UNREF(Expr)>::result_type
-            type;
-        };
+          : proto::result_of::eval<UNREF(Expr), Context>
+        {};
 
         template<typename Expr>
-        typename result<eval_fun(Expr)>::type
+        typename proto::result_of::eval<Expr, Context>::type
         operator()(Expr &expr) const
         {
             return proto::eval(expr, this->ctx_);