2015-03-09 11:50:10 +01:00
										 
									 
								 
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								// Copyright (C) 2014 Andrzej Krzemienski.
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								//
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								// Use, modification, and distribution is subject to the Boost Software
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								// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
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								// http://www.boost.org/LICENSE_1_0.txt)
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								//
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								// See http://www.boost.org/lib/optional for documentation.
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								//
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								// You are welcome to contact the author at: akrzemi1@gmail.com
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								#include "boost/optional/optional.hpp"
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											2020-03-30 14:04:35 -04:00
										 
									 
								 
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								#ifdef BOOST_BORLANDC
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											2015-03-09 11:50:10 +01:00
										 
									 
								 
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								#pragma hdrstop
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								#endif
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								#include <string>
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								#include "boost/core/addressof.hpp"
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								#include "boost/core/lightweight_test.hpp"
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								using boost::optional;
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								std::string global("text"); 
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								optional<std::string&> make_optional_string_ref()
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								{
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								  return optional<std::string&>(global);
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								}
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								std::string& return_global()
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								{
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								  return global;
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								}
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								int main()
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								{
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								  optional<std::string&> opt;
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								  opt = make_optional_string_ref();
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								  BOOST_TEST(bool(opt));
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								  BOOST_TEST(*opt == global);
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								  BOOST_TEST(boost::addressof(*opt) == boost::addressof(global));
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								  {
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								    std::string& str = *make_optional_string_ref();
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								    BOOST_TEST(str == global);
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								    BOOST_TEST(boost::addressof(str) == boost::addressof(global));
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								  }
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								  {
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								    std::string& str = make_optional_string_ref().value();
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								    BOOST_TEST(str == global);
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								    BOOST_TEST(boost::addressof(str) == boost::addressof(global));
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								  }
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								  {
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								    std::string& str = make_optional_string_ref().value_or(global);
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								    BOOST_TEST(str == global);
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								    BOOST_TEST(boost::addressof(str) == boost::addressof(global));
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								  }
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								  {
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								    std::string& str = make_optional_string_ref().value_or_eval(&return_global);
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								    BOOST_TEST(str == global);
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								    BOOST_TEST(boost::addressof(str) == boost::addressof(global));
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								  }
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								  return boost::report_errors();
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								}
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