[Boost-commit] svn:boost r73614 - in sandbox/coerce/boost/coerce: . detail

Subject: [Boost-commit] svn:boost r73614 - in sandbox/coerce/boost/coerce: . detail
From: vexocide_at_[hidden]
Date: 2011-08-08 15:56:47

Author: vexocide
Date: 2011-08-08 15:56:45 EDT (Mon, 08 Aug 2011)
New Revision: 73614
URL: http://svn.boost.org/trac/boost/changeset/73614

Log:
Explicitly check if the type is a tag
Added:
   sandbox/coerce/boost/coerce/detail/tag.hpp   (contents, props changed)
Text files modified: 
   sandbox/coerce/boost/coerce/coerce.hpp |     6 +++---                                  
   1 files changed, 3 insertions(+), 3 deletions(-)

Modified: sandbox/coerce/boost/coerce/coerce.hpp
==============================================================================
--- sandbox/coerce/boost/coerce/coerce.hpp	(original)
+++ sandbox/coerce/boost/coerce/coerce.hpp	2011-08-08 15:56:45 EDT (Mon, 08 Aug 2011)
@@ -12,12 +12,12 @@
 #endif
 
 #include <boost/coerce/detail/backend.hpp>
+#include <boost/coerce/detail/tag.hpp>
 #include <boost/coerce/sequence.hpp>
 #include <boost/coerce/string.hpp>
 #include <boost/coerce/tag.hpp>
 
 #include <boost/throw_exception.hpp>
-#include <boost/type_traits/is_same.hpp>
 #include <boost/utility/enable_if.hpp>
 
 #include <typeinfo>  // for std::bad_cast
@@ -67,8 +67,8 @@
     }
 
     template <typename Target, typename Source, typename Tag>
-    inline typename disable_if<
-        is_same<Target, Tag>, Target>::type
+    inline typename enable_if<
+        detail::is_tag<Tag>, Target>::type
     as_default(
         Source const & source,
         Tag const & tag,

Added: sandbox/coerce/boost/coerce/detail/tag.hpp
==============================================================================
--- (empty file)
+++ sandbox/coerce/boost/coerce/detail/tag.hpp	2011-08-08 15:56:45 EDT (Mon, 08 Aug 2011)
@@ -0,0 +1,31 @@
+//              Copyright Jeroen Habraken 2011.
+//
+// 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_COERCE_DETAIL_TAG_HPP
+#define BOOST_COERCE_DETAIL_TAG_HPP
+
+#ifdef _MSC_VER
+#pragma once
+#endif
+
+#include <boost/mpl/has_xxx.hpp>
+#include <boost/mpl/or.hpp>
+
+namespace boost { namespace coerce { namespace detail {
+
+    BOOST_MPL_HAS_XXX_TEMPLATE_DEF(parser)
+    BOOST_MPL_HAS_XXX_TEMPLATE_DEF(generator)
+
+    template <typename T>
+    struct is_tag
+        : mpl::or_<
+            has_parser<T>,
+            has_generator<T>
+        > { };
+
+} } }  // namespace boost::coerce::detail
+
+#endif  // BOOST_COERCE_DETAIL_TAG_HPP