split utility.hpp header

[SVN r17472]

include/boost/next_prior.hpp

@@ -0,0 +1,33 @@
+//  Boost next_prior.hpp header file  ---------------------------------------//
+
+//  (C) Copyright Boost.org 1999-2003. Permission to copy, use, modify, sell
+//  and distribute this software is granted provided this copyright
+//  notice appears in all copies. This software is provided "as is" without
+//  express or implied warranty, and with no claim as to its suitability for
+//  any purpose.
+
+//  See http://www.boost.org/libs/utility for documentation.
+
+#ifndef BOOST_NEXT_PRIOR_HPP_INCLUDED
+#define BOOST_NEXT_PRIOR_HPP_INCLUDED
+
+namespace boost {
+
+//  Helper functions for classes like bidirectional iterators not supporting
+//  operator+ and operator-
+//
+//  Usage:
+//    const std::list<T>::iterator p = get_some_iterator();
+//    const std::list<T>::iterator prev = boost::prior(p);
+
+//  Contributed by Dave Abrahams
+
+template <class T>
+inline T next(T x) { return ++x; }
+
+template <class T>
+inline T prior(T x) { return --x; }
+
+} // namespace boost
+
+#endif  // BOOST_NEXT_PRIOR_HPP_INCLUDED