Qpid Proton C++ API  0.33.0
null.hpp
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1 #ifndef PROTON_NULL_HPP
2 #define PROTON_NULL_HPP
3 
4 /*
5  *
6  * Licensed to the Apache Software Foundation (ASF) under one
7  * or more contributor license agreements. See the NOTICE file
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14  * http://www.apache.org/licenses/LICENSE-2.0
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24 
27 
28 #include "./internal/config.hpp"
29 #include "./internal/comparable.hpp"
30 #include "./internal/export.hpp"
31 
32 #include <iosfwd>
33 
34 namespace proton {
35 
39 class null : private internal::comparable<null> {
40  public:
41  null() {}
42 #if PN_CPP_HAS_NULLPTR
43  null(decltype(nullptr)) {}
45 #endif
46  friend bool operator==(const null&, const null&) { return true; }
49  friend bool operator<(const null&, const null&) { return false; }
50 };
51 
53 PN_CPP_EXTERN std::ostream& operator<<(std::ostream&, const null&);
54 
55 }
56 
57 #endif // PROTON_NULL_HPP
proton::operator<<
std::ostream & operator<<(std::ostream &, const binary &)
Print a binary value.
proton::null
The type of the AMQP null value.
Definition: null.hpp:39
proton::null::operator<
friend bool operator<(const null &, const null &)
null instances are never unequal
Definition: null.hpp:49
proton
The main Proton namespace.
Definition: annotation_key.hpp:33
proton::null::operator==
friend bool operator==(const null &, const null &)
null instances are always equal
Definition: null.hpp:47