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// Copyright (C) 2021 Andrzej Krzemienski.
//
// 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"
#include "boost/core/lightweight_test.hpp"
#include "boost/none.hpp"
//#ifndef BOOST_OPTIONAL_NO_CONVERTING_COPY_CTOR
using boost::optional;
struct implicit_bool_conv
{
operator bool() const { return false; }
};
struct explicit_bool_conv
{
explicit operator bool() const BOOST_NOEXCEPT { return true; }
};
template <typename To, typename From>
void test_convert_assign()
{
optional<To> oi;
oi = From();
BOOST_TEST(oi);
}
void test_no_bad_assignment()
{
#if !defined(BOOST_NO_CXX11_DECLTYPE) && !BOOST_WORKAROUND(BOOST_MSVC, < 1800)
// this means that type trait `boost::is_assignable` works.
static_assert((boost::is_assignable<optional<bool>&, bool>::value), "ERROR");
static_assert((boost::is_assignable<optional<bool>&, implicit_bool_conv>::value), "ERROR");
static_assert((! boost::is_assignable<optional<bool>&, explicit_bool_conv>::value), "ERROR");
#endif
}
int main()
{
test_convert_assign<int, short>();
test_convert_assign<bool, implicit_bool_conv>();
test_no_bad_assignment();
return boost::report_errors();
}
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