summaryrefslogtreecommitdiff
path: root/boost/bimap/tags/support/apply_to_value_type.hpp
diff options
context:
space:
mode:
Diffstat (limited to 'boost/bimap/tags/support/apply_to_value_type.hpp')
-rw-r--r--boost/bimap/tags/support/apply_to_value_type.hpp70
1 files changed, 70 insertions, 0 deletions
diff --git a/boost/bimap/tags/support/apply_to_value_type.hpp b/boost/bimap/tags/support/apply_to_value_type.hpp
new file mode 100644
index 0000000..bb6aa60
--- /dev/null
+++ b/boost/bimap/tags/support/apply_to_value_type.hpp
@@ -0,0 +1,70 @@
+// Boost.Bimap
+//
+// Copyright (c) 2006-2007 Matias Capeletto
+//
+// 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)
+
+/// \file tags/support/apply_to_value_type.hpp
+/// \brief Similar to mpl::apply but for tagged types.
+
+#ifndef BOOST_BIMAP_TAGS_SUPPORT_APPLY_TO_VALUE_TYPE_HPP
+#define BOOST_BIMAP_TAGS_SUPPORT_APPLY_TO_VALUE_TYPE_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER>=1200)
+#pragma once
+#endif
+
+#include <boost/config.hpp>
+
+#include <boost/bimap/tags/tagged.hpp>
+#include <boost/mpl/apply.hpp>
+
+/** \struct boost::bimaps::tags::support::apply_to_value_type
+\brief Higger order metafunction similar to mpl::apply but for tagged types.
+
+\code
+template< class Metafunction, class TaggedType >
+struct apply_to_value_type
+{
+ typedef tagged
+ <
+ Metafuntion< value_type_of< TaggedType >::type >::type,
+ tag_of< TaggedType >::type
+
+ > type;
+};
+\endcode
+
+This higher order metafunctions is very useful, and it can be used with lambda
+expresions.
+
+See also tagged.
+ **/
+
+#ifndef BOOST_BIMAP_DOXYGEN_WILL_NOT_PROCESS_THE_FOLLOWING_LINES
+
+namespace boost {
+namespace bimaps {
+namespace tags {
+namespace support {
+
+template < class F, class TaggedType >
+struct apply_to_value_type;
+
+template < class F, class ValueType, class Tag >
+struct apply_to_value_type<F, tagged<ValueType,Tag> >
+{
+ typedef BOOST_DEDUCED_TYPENAME mpl::apply< F, ValueType >::type new_value_type;
+ typedef tagged< new_value_type, Tag > type;
+};
+
+} // namespace support
+} // namespace tags
+} // namespace bimaps
+} // namespace boost
+
+#endif // BOOST_BIMAP_DOXYGEN_WILL_NOT_PROCESS_THE_FOLLOWING_LINES
+
+#endif // BOOST_BIMAP_TAGS_SUPPORT_APPLY_TO_VALUE_TYPE_HPP