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Diffstat (limited to 'indexlib/boost-compat/next_prior.h')
-rw-r--r-- | indexlib/boost-compat/next_prior.h | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/indexlib/boost-compat/next_prior.h b/indexlib/boost-compat/next_prior.h new file mode 100644 index 000000000..cdacf29c7 --- /dev/null +++ b/indexlib/boost-compat/next_prior.h @@ -0,0 +1,51 @@ +// Boost next_prior.h 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_H_INCLUDED +#define BOOST_NEXT_PRIOR_H_INCLUDED + +#include <iterator> + +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 + +template <class T> +inline T next(T x) { return ++x; } + +template <class T, class Distance> +inline T next(T x, Distance n) +{ + std::advance(x, n); + return x; +} + +template <class T> +inline T prior(T x) { return --x; } + +template <class T, class Distance> +inline T prior(T x, Distance n) +{ + std::advance(x, -n); + return x; +} + +} // namespace boost + +#endif // BOOST_NEXT_PRIOR_H_INCLUDED |