summaryrefslogtreecommitdiff
path: root/src/third_party/boost-1.60.0/boost/next_prior.hpp
diff options
context:
space:
mode:
Diffstat (limited to 'src/third_party/boost-1.60.0/boost/next_prior.hpp')
-rw-r--r--src/third_party/boost-1.60.0/boost/next_prior.hpp165
1 files changed, 165 insertions, 0 deletions
diff --git a/src/third_party/boost-1.60.0/boost/next_prior.hpp b/src/third_party/boost-1.60.0/boost/next_prior.hpp
new file mode 100644
index 00000000000..7854ec436a4
--- /dev/null
+++ b/src/third_party/boost-1.60.0/boost/next_prior.hpp
@@ -0,0 +1,165 @@
+// Boost next_prior.hpp header file ---------------------------------------//
+
+// (C) Copyright Dave Abrahams and Daniel Walker 1999-2003. 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)
+
+// See http://www.boost.org/libs/utility for documentation.
+
+// Revision History
+// 13 Dec 2003 Added next(x, n) and prior(x, n) (Daniel Walker)
+
+#ifndef BOOST_NEXT_PRIOR_HPP_INCLUDED
+#define BOOST_NEXT_PRIOR_HPP_INCLUDED
+
+#include <iterator>
+#if defined(_MSC_VER) && _MSC_VER <= 1310
+#include <boost/mpl/and.hpp>
+#include <boost/type_traits/is_integral.hpp>
+#endif
+#include <boost/type_traits/is_unsigned.hpp>
+#include <boost/type_traits/integral_promotion.hpp>
+#include <boost/type_traits/make_signed.hpp>
+#include <boost/type_traits/has_plus.hpp>
+#include <boost/type_traits/has_plus_assign.hpp>
+#include <boost/type_traits/has_minus.hpp>
+#include <boost/type_traits/has_minus_assign.hpp>
+
+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);
+// const std::list<T>::iterator next = boost::next(prev, 2);
+
+// Contributed by Dave Abrahams
+
+namespace next_prior_detail {
+
+template< typename T, typename Distance, bool HasPlus = has_plus< T, Distance >::value >
+struct next_impl2
+{
+ static T call(T x, Distance n)
+ {
+ std::advance(x, n);
+ return x;
+ }
+};
+
+template< typename T, typename Distance >
+struct next_impl2< T, Distance, true >
+{
+ static T call(T x, Distance n)
+ {
+ return x + n;
+ }
+};
+
+
+template< typename T, typename Distance, bool HasPlusAssign = has_plus_assign< T, Distance >::value >
+struct next_impl1 :
+ public next_impl2< T, Distance >
+{
+};
+
+template< typename T, typename Distance >
+struct next_impl1< T, Distance, true >
+{
+ static T call(T x, Distance n)
+ {
+ x += n;
+ return x;
+ }
+};
+
+
+template<
+ typename T,
+ typename Distance,
+ typename PromotedDistance = typename integral_promotion< Distance >::type,
+#if !defined(_MSC_VER) || _MSC_VER > 1310
+ bool IsUInt = is_unsigned< PromotedDistance >::value
+#else
+ // MSVC 7.1 has problems with applying is_unsigned to non-integral types
+ bool IsUInt = mpl::and_< is_integral< PromotedDistance >, is_unsigned< PromotedDistance > >::value
+#endif
+>
+struct prior_impl3
+{
+ static T call(T x, Distance n)
+ {
+ std::advance(x, -n);
+ return x;
+ }
+};
+
+template< typename T, typename Distance, typename PromotedDistance >
+struct prior_impl3< T, Distance, PromotedDistance, true >
+{
+ static T call(T x, Distance n)
+ {
+ typedef typename make_signed< PromotedDistance >::type signed_distance;
+ std::advance(x, -static_cast< signed_distance >(static_cast< PromotedDistance >(n)));
+ return x;
+ }
+};
+
+
+template< typename T, typename Distance, bool HasMinus = has_minus< T, Distance >::value >
+struct prior_impl2 :
+ public prior_impl3< T, Distance >
+{
+};
+
+template< typename T, typename Distance >
+struct prior_impl2< T, Distance, true >
+{
+ static T call(T x, Distance n)
+ {
+ return x - n;
+ }
+};
+
+
+template< typename T, typename Distance, bool HasMinusAssign = has_minus_assign< T, Distance >::value >
+struct prior_impl1 :
+ public prior_impl2< T, Distance >
+{
+};
+
+template< typename T, typename Distance >
+struct prior_impl1< T, Distance, true >
+{
+ static T call(T x, Distance n)
+ {
+ x -= n;
+ return x;
+ }
+};
+
+} // namespace next_prior_detail
+
+template <class T>
+inline T next(T x) { return ++x; }
+
+template <class T, class Distance>
+inline T next(T x, Distance n)
+{
+ return next_prior_detail::next_impl1< T, Distance >::call(x, n);
+}
+
+template <class T>
+inline T prior(T x) { return --x; }
+
+template <class T, class Distance>
+inline T prior(T x, Distance n)
+{
+ return next_prior_detail::prior_impl1< T, Distance >::call(x, n);
+}
+
+} // namespace boost
+
+#endif // BOOST_NEXT_PRIOR_HPP_INCLUDED