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// Copyright 2022 (c) Andrey Semashev
// 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/config.hpp>
#include <boost/core/lightweight_test.hpp>
#include <boost/iterator/function_output_iterator.hpp>
#include <iterator>
namespace {
struct sum_func
{
typedef void result_type;
explicit sum_func(int& n) : m_n(n) {}
result_type operator() (int x) const
{
m_n += x;
}
private:
int& m_n;
};
} // namespace
int main()
{
{
int n = 0;
boost::iterators::function_output_iterator< sum_func > it =
boost::iterators::make_function_output_iterator(sum_func(n));
*it = 1;
++it;
*it = 2;
++it;
*it = 3;
BOOST_TEST_EQ(n, 6);
}
{
int n = 0;
auto it = boost::iterators::make_function_output_iterator([&n](int x) { n -= x; });
*it = 1;
++it;
*it = 2;
++it;
*it = 3;
BOOST_TEST_EQ(n, -6);
}
#if defined(__cpp_lib_concepts) && ( __cpp_lib_concepts >= 202002L )
{
auto func = [](int) {};
static_assert(std::output_iterator< boost::iterators::function_output_iterator< decltype(func) >, int >);
}
#endif
return boost::report_errors();
}
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