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// Copyright (C) 2019 T. Zachary Laine
//
// 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)
//[ random_access_iterator
#include <boost/stl_interfaces/iterator_interface.hpp>
#include <algorithm>
#include <array>
#include <cassert>
// This is a minimal random access iterator. It uses default template
// parameters for most stl_interfaces template parameters.
struct simple_random_access_iterator
: boost::stl_interfaces::iterator_interface<
#if !BOOST_STL_INTERFACES_USE_DEDUCED_THIS
simple_random_access_iterator,
#endif
std::random_access_iterator_tag,
int>
{
// This default constructor does not initialize it_, since that's how int *
// works as well. This allows optimum performance in code paths where
// initializing a single pointer may be measurable. It is also a
// reasonable choice to initialize with nullptr.
simple_random_access_iterator() noexcept {}
simple_random_access_iterator(int * it) noexcept : it_(it) {}
int & operator*() const noexcept { return *it_; }
simple_random_access_iterator & operator+=(std::ptrdiff_t i) noexcept
{
it_ += i;
return *this;
}
auto operator-(simple_random_access_iterator other) const noexcept
{
return it_ - other.it_;
}
private:
int * it_;
};
int main()
{
std::array<int, 10> ints = {{0, 2, 1, 3, 4, 5, 7, 6, 8, 9}};
simple_random_access_iterator first(ints.data());
simple_random_access_iterator last(ints.data() + ints.size());
std::sort(first, last);
assert(ints == (std::array<int, 10>{{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}}));
}
//]
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