9 Iterators library [iterators]

9.7 Iterator adaptors [iterators.predef]

9.7.3 Move iterators and sentinels [iterators.move]

9.7.3.3 Class template move_sentinel [move.sentinel]

1

Class template move_sentinel is a sentinel adaptor useful for denoting ranges together with move_iterator. When an input iterator type I and sentinel type S satisfy Sentinel<S, I>, Sentinel<move_sentinel<S>, move_iterator<I>> is satisfied as well.

2

[ Example: A move_if algorithm is easily implemented with copy_if using move_iterator and move_sentinel:

template <InputIterator I, Sentinel<I> S, WeaklyIncrementable O,
          IndirectUnaryPredicate<I> Pred>
  requires IndirectlyMovable<I, O>
void move_if(I first, S last, O out, Pred pred){
  copy_if(move_iterator<I>{first}, move_sentinel<S>{last}, out, pred);
}

 — end example ]

namespace std { namespace experimental { namespace ranges { inline namespace v1 {
  template <Semiregular S>
  class move_sentinel {
  public:
    constexpr move_sentinel();
    explicit move_sentinel(S s);
    move_sentinel(const move_sentinel<ConvertibleTo<S>>& s);
    move_sentinel& operator=(const move_sentinel<ConvertibleTo<S>>& s);

    S base() const;

  private:
    S last; // exposition only
  };

  template <class I, Sentinel<I> S>
    constexpr bool operator==(
      const move_iterator<I>& i, const move_sentinel<S>& s);
  template <class I, Sentinel<I> S>
    constexpr bool operator==(
      const move_sentinel<S>& s, const move_iterator<I>& i);
  template <class I, Sentinel<I> S>
    constexpr bool operator!=(
      const move_iterator<I>& i, const move_sentinel<S>& s);
  template <class I, Sentinel<I> S>
    constexpr bool operator!=(
      const move_sentinel<S>& s, const move_iterator<I>& i);

  template <class I, SizedSentinel<I> S>
    constexpr difference_type_t<I> operator-(
      const move_sentinel<S>& s, const move_iterator<I>& i);
  template <class I, SizedSentinel<I> S>
    constexpr difference_type_t<I> operator-(
      const move_iterator<I>& i, const move_sentinel<S>& s);

  template <Semiregular S>
    constexpr move_sentinel<S> make_move_sentinel(S s);
}}}}