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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)
#include <boost/stl_interfaces/iterator_interface.hpp>
#include <boost/core/lightweight_test.hpp>
#include <array>
#include <numeric>
#include <vector>
#include <type_traits>
struct basic_output_iter
: boost::stl_interfaces::iterator_interface<
#if !BOOST_STL_INTERFACES_USE_DEDUCED_THIS
basic_output_iter,
#endif
std::output_iterator_tag, int>
{
basic_output_iter() : it_(nullptr) {}
basic_output_iter(int * it) : it_(it) {}
int & operator*() noexcept { return *it_; }
basic_output_iter & operator++() noexcept
{
++it_;
return *this;
}
using base_type = boost::stl_interfaces::iterator_interface<
#if !BOOST_STL_INTERFACES_USE_DEDUCED_THIS
basic_output_iter,
#endif
std::output_iterator_tag, int>;
using base_type::operator++;
private:
int * it_;
};
using output = basic_output_iter;
#if BOOST_STL_INTERFACES_USE_CONCEPTS
static_assert(std::output_iterator<output, int>, "");
BOOST_STL_INTERFACES_STATIC_ASSERT_ITERATOR_TRAITS(
output,
void,
std::output_iterator_tag,
void,
void,
void,
std::ptrdiff_t)
#else
BOOST_STL_INTERFACES_STATIC_ASSERT_ITERATOR_TRAITS(
output,
std::output_iterator_tag,
std::output_iterator_tag,
int,
int &,
void,
std::ptrdiff_t)
#endif
template<typename Container>
struct back_insert_iter : boost::stl_interfaces::iterator_interface<
#if !BOOST_STL_INTERFACES_USE_DEDUCED_THIS
back_insert_iter<Container>,
#endif
std::output_iterator_tag,
typename Container::value_type,
back_insert_iter<Container> &>
{
back_insert_iter() : c_(nullptr) {}
back_insert_iter(Container & c) : c_(std::addressof(c)) {}
back_insert_iter & operator*() noexcept { return *this; }
back_insert_iter & operator++() noexcept { return *this; }
back_insert_iter & operator=(typename Container::value_type const & v)
{
c_->push_back(v);
return *this;
}
back_insert_iter & operator=(typename Container::value_type && v)
{
c_->push_back(std::move(v));
return *this;
}
using base_type = boost::stl_interfaces::iterator_interface<
#if !BOOST_STL_INTERFACES_USE_DEDUCED_THIS
back_insert_iter<Container>,
#endif
std::output_iterator_tag,
typename Container::value_type,
back_insert_iter<Container> &>;
using base_type::operator++;
private:
Container * c_;
};
using back_insert = back_insert_iter<std::vector<int>>;
#if BOOST_STL_INTERFACES_USE_CONCEPTS
static_assert(std::output_iterator<back_insert, int>, "");
BOOST_STL_INTERFACES_STATIC_ASSERT_ITERATOR_TRAITS(
back_insert,
void,
std::output_iterator_tag,
void,
void,
void,
std::ptrdiff_t)
#else
BOOST_STL_INTERFACES_STATIC_ASSERT_ITERATOR_TRAITS(
back_insert,
std::output_iterator_tag,
std::output_iterator_tag,
int,
back_insert &,
void,
std::ptrdiff_t)
#endif
std::vector<int> ints = {{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}};
int main()
{
{
std::vector<int> ints_copy(ints.size());
std::copy(ints.begin(), ints.end(), output(&ints_copy[0]));
BOOST_TEST(ints_copy == ints);
}
{
std::vector<int> ints_copy;
std::copy(ints.begin(), ints.end(), back_insert(ints_copy));
BOOST_TEST(ints_copy == ints);
}
return boost::report_errors();
}
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