ceph/src/boost/libs/iterator/doc/zip_iterator_abstract.rst

   1 .. Copyright David Abrahams 2006. Distributed under the Boost
   2 .. Software License, Version 1.0. (See accompanying
   3 .. file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   4
   5 The zip iterator provides the ability to parallel-iterate
   6 over several controlled sequences simultaneously. A zip
   7 iterator is constructed from a tuple of iterators. Moving
   8 the zip iterator moves all the iterators in parallel.
   9 Dereferencing the zip iterator returns a tuple that contains
  10 the results of dereferencing the individual iterators.
  11
  12 The tuple of iterators is now implemented in terms of a Boost fusion sequence.
  13 Because of this the 'tuple' may be any Boost fusion sequence and, for backwards
  14 compatibility through a Boost fusion sequence adapter, a Boost tuple. Because the
  15 'tuple' may be any boost::fusion sequence the 'tuple' may also be any type for which a
  16 Boost fusion adapter exists. This includes, among others, a std::tuple and a std::pair.
  17 Just remember to include the appropriate Boost fusion adapter header files for these
  18 other Boost fusion adapters. The zip_iterator header file already includes the
  19 Boost fusion adapter header file for Boost tuple, so you need not include it yourself
  20 to use a Boost tuple as your 'tuple'.