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#ifndef PROTON_NULL_HPP
#define PROTON_NULL_HPP
/*
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*
*/
/// @file
/// @copybrief proton::null
#include "./internal/comparable.hpp"
#include "./internal/export.hpp"
#include <iosfwd>
namespace proton {
/// The type of the AMQP null value
///
/// @see @ref types_page
class null : private internal::comparable<null> {
public:
null() = default;
/// Constructed from nullptr literal
null(decltype(nullptr)) {}
/// null instances are always equal
friend bool operator==(const null&, const null&) { return true; }
/// null instances are never unequal
friend bool operator<(const null&, const null&) { return false; }
};
/// Print a null value
PN_CPP_EXTERN std::ostream& operator<<(std::ostream&, const null&);
}
#endif // PROTON_NULL_HPP
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