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// Copyright (C) 2014 Andrzej Krzemienski.
// Copyright (C) 2024 Alexander Grund
//
// Use, modification, and distribution is subject to 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)
//
// See http://www.boost.org/lib/optional for documentation.
//
// You are welcome to contact the author at:
// akrzemi1@gmail.com
#include "boost/optional/optional.hpp"
#ifdef BOOST_BORLANDC
#pragma hdrstop
#endif
#include "boost/core/lightweight_test.hpp"
#include "boost/none.hpp"
struct SemiRegular // no operator==
{
private: void operator==(SemiRegular const&) const {}
private: void operator!=(SemiRegular const&) const {}
};
void test_equal_to_none_of_noncomparable_T()
{
boost::optional<SemiRegular> i = SemiRegular();
boost::optional<SemiRegular> o;
BOOST_TEST(i != boost::none);
BOOST_TEST(boost::none != i);
BOOST_TEST(o == boost::none);
BOOST_TEST(boost::none == o);
}
void test_comparison_to_none()
{
using boost::none;
boost::optional<SemiRegular> i = SemiRegular();
// the default ordering of optional<size_t> is{ boost::none, 0, 1, 2, ... }
// Hence boost::none < i for any engaged i
// and all others operators ( ==, !=, <, <=, >, >= ) follow
BOOST_TEST(!(i == none));
BOOST_TEST(i != none);
BOOST_TEST(!(i < none));
BOOST_TEST(!(i <= none));
BOOST_TEST(i > none);
BOOST_TEST(i >= none);
// Comparison is symmetric
BOOST_TEST(!(none == i));
BOOST_TEST(none != i);
BOOST_TEST(none < i);
BOOST_TEST(none <= i);
BOOST_TEST(!(none > i));
BOOST_TEST(!(none >= i));
// An un-engaged optional is always equal to none
boost::optional<SemiRegular> o;
BOOST_TEST(o == none);
BOOST_TEST(!(o != none));
BOOST_TEST(!(o < none));
BOOST_TEST(o <= none);
BOOST_TEST(!(o > none));
BOOST_TEST(o >= none);
// Comparison is symmetric
BOOST_TEST(none == o);
BOOST_TEST(!(none != o));
BOOST_TEST(!(none < o));
BOOST_TEST(none <= o);
BOOST_TEST(!(none > o));
BOOST_TEST(none >= o);
}
int main()
{
test_equal_to_none_of_noncomparable_T();
return boost::report_errors();
}
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