ceph/src/boost/boost/algorithm/cxx17/for_each_n.hpp

   1 /*
   2    Copyright (c) Marshall Clow 2017.
   3
   4    Distributed under the Boost Software License, Version 1.0. (See accompanying
   5    file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 */
   7
   8 /// \file  for_each_n.hpp
   9 /// \brief Apply a functor to the elements of a sequence
  10 /// \author Marshall Clow
  11
  12 #ifndef BOOST_ALGORITHM_FOR_EACH_N_HPP
  13 #define BOOST_ALGORITHM_FOR_EACH_N_HPP
  14
  15 #include <utility>      // for std::pair
  16
  17 #include <boost/config.hpp>
  18
  19 namespace boost { namespace algorithm {
  20
  21 /// \fn for_each_n(InputIterator first, Size n, Function f);
  22 /// \return first + n
  23 ///
  24 /// \param first    The start of the first range.
  25 /// \param n        One past the end of the first range.
  26 /// \param f        A functor to apply to the elements of the sequence
  27 /// \note           If f returns a result, the result is ignored.
  28 template<class InputIterator, class Size, class Function>
  29 InputIterator for_each_n(InputIterator first, Size n, Function f)
  30 {
  31     for ( ; n > 0; --n, ++first )
  32         f(*first);
  33
  34     return first;
  35 }
  36
  37 }} // namespace boost and algorithm
  38
  39 #endif // BOOST_ALGORITHM_FOR_EACH_N_HPP