[Boost-commit] svn:boost r63086 - trunk/boost/spirit/home/qi/action

Subject: [Boost-commit] svn:boost r63086 - trunk/boost/spirit/home/qi/action
From: hartmut.kaiser_at_[hidden]
Date: 2010-06-18 17:49:54

Author: hkaiser
Date: 2010-06-18 17:49:51 EDT (Fri, 18 Jun 2010)
New Revision: 63086
URL: http://svn.boost.org/trac/boost/changeset/63086

Log:
Spirit: fixed backtracking problem if semantic action makes parse fail retrospectively
Text files modified: 
   trunk/boost/spirit/home/qi/action/action.hpp |     8 +++++++-                                
   1 files changed, 7 insertions(+), 1 deletions(-)

Modified: trunk/boost/spirit/home/qi/action/action.hpp
==============================================================================
--- trunk/boost/spirit/home/qi/action/action.hpp	(original)
+++ trunk/boost/spirit/home/qi/action/action.hpp	2010-06-18 17:49:51 EDT (Fri, 18 Jun 2010)
@@ -59,11 +59,17 @@
             typename make_attribute::type made_attr = make_attribute::call(attr_);
             typename transform::type attr = transform::pre(made_attr);
 
+            Iterator save = first;
             if (subject.parse(first, last, context, skipper, attr))
             {
                 // call the function, passing the attribute, the context.
                 // The client can return false to fail parsing.
-                return traits::action_dispatch<Subject>()(f, attr, context);
+                if (traits::action_dispatch<Subject>()(f, attr, context))
+                    return true;
+
+                // reset iterators if semantic action failed the match 
+                // retrospectively
+                first = save;
             }
             return false;
         }