cpp-useful-iterators/include/iterator/sentinel_iterator.h

//
//  sentinel_iterator.h
//  iterator
//
//  Created by Sam Jaffe on 3/30/23.
//  Copyright © 2023 Sam Jaffe. All rights reserved.
//

#pragma once

#include <iterator/forwards.h>
#include <iterator/proxy.h>

namespace iterator {
template <typename It, typename S>
class sentinel_iterator : public proxy<It, sentinel_iterator<It, S>> {
public:
  using super_t = proxy<It, sentinel_iterator<It, S>>;
  using sentinel_type = sentinel_iterator;

public:
  using super_t::super_t;
  sentinel_iterator(S) : super_t() {}

  bool equal_to(sentinel_iterator const & other) const {
    return (at_end() && other.at_end()) || super_t::impl() == other.impl();
  }
  bool at_end() const { return super_t::impl() == S(); }
};
}

MAKE_ITERATOR_FACADE_TYPEDEFS_T(::iterator::sentinel_iterator);