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/*
Copyright 2022 Glen Joseph Fernandes
(glenjofe@gmail.com)
Distributed under the Boost Software License, Version 1.0.
(http://www.boost.org/LICENSE_1_0.txt)
*/
#include <boost/config.hpp>
#if !defined(BOOST_NO_CXX11_CONSTEXPR)
#include <boost/core/empty_value.hpp>
#include <boost/core/lightweight_test.hpp>
struct empty {
constexpr int value() const {
return 1;
}
};
class type {
public:
explicit constexpr type(int count)
: value_(count) { }
constexpr int value() const {
return value_;
}
private:
int value_;
};
void test_int()
{
constexpr boost::empty_value<int> v(boost::empty_init_t(), 4);
constexpr int c = v.get();
BOOST_TEST_EQ(c, 4);
}
void test_empty()
{
constexpr boost::empty_value<empty> v = boost::empty_init_t();
constexpr int c = v.get().value();
BOOST_TEST_EQ(c, 1);
}
void test_type()
{
constexpr boost::empty_value<type> v(boost::empty_init_t(), 2);
constexpr int c = v.get().value();
BOOST_TEST_EQ(c, 2);
}
int main()
{
test_int();
test_empty();
test_type();
return boost::report_errors();
}
#else
int main()
{
return 0;
}
#endif
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