Qpid Proton C++ API  0.36.0
null.hpp
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1 #ifndef PROTON_NULL_HPP
2 #define PROTON_NULL_HPP
3 
4 /*
5  *
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24 
27 
28 #include "./internal/comparable.hpp"
29 #include "./internal/export.hpp"
30 
31 #include <iosfwd>
32 
33 namespace proton {
34 
38 class null : private internal::comparable<null> {
39  public:
40  null() {}
42  null(decltype(nullptr)) {}
43 
45  friend bool operator==(const null&, const null&) { return true; }
47  friend bool operator<(const null&, const null&) { return false; }
48 };
49 
51 PN_CPP_EXTERN std::ostream& operator<<(std::ostream&, const null&);
52 
53 }
54 
55 #endif // PROTON_NULL_HPP
The type of the AMQP null value.
Definition: null.hpp:38
friend bool operator==(const null &, const null &)
null instances are always equal
Definition: null.hpp:45
friend bool operator<(const null &, const null &)
null instances are never unequal
Definition: null.hpp:47
The main Proton namespace.
Definition: annotation_key.hpp:33
std::ostream & operator<<(std::ostream &, const binary &)
Print a binary value.