connection.hpp
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21 
22 #ifndef NDN_UTIL_SIGNAL_CONNECTION_HPP
23 #define NDN_UTIL_SIGNAL_CONNECTION_HPP
24 
26 
27 namespace ndn {
28 namespace util {
29 namespace signal {
30 
31 using DisconnectFunction = std::function<void()>;
32 
37 {
38 public:
39  constexpr
40  Connection() noexcept = default;
41 
48  void
49  disconnect();
50 
53  bool
54  isConnected() const noexcept
55  {
56  return !m_disconnect.expired();
57  }
58 
59 private:
62  explicit
63  Connection(weak_ptr<DisconnectFunction> disconnect) noexcept;
64 
65  template<typename Owner, typename ...TArgs>
66  friend class Signal;
67 
68 private:
69  // NOTE: the following "hidden friend" operators are available via
70  // argument-dependent lookup only and must be defined inline.
71 
77  friend bool
78  operator==(const Connection& lhs, const Connection& rhs) noexcept
79  {
80  return (!lhs.isConnected() && !rhs.isConnected()) ||
81  (!lhs.m_disconnect.owner_before(rhs.m_disconnect) &&
82  !rhs.m_disconnect.owner_before(lhs.m_disconnect));
83  }
84 
85  friend bool
86  operator!=(const Connection& lhs, const Connection& rhs) noexcept
87  {
88  return !(lhs == rhs);
89  }
90 
91 private:
99  weak_ptr<DisconnectFunction> m_disconnect;
100 };
101 
102 } // namespace signal
103 } // namespace util
104 } // namespace ndn
105 
106 #endif // NDN_UTIL_SIGNAL_CONNECTION_HPP
Definition: data.cpp:26
constexpr Connection() noexcept=default
friend bool operator!=(const Connection &lhs, const Connection &rhs) noexcept
Definition: connection.hpp:86
represents a connection to a signal
Definition: connection.hpp:36
provides a lightweight signal / event system
Definition: signal.hpp:52
void disconnect()
disconnects from the signal
Definition: connection.cpp:36
Common includes and macros used throughout the library.
friend bool operator==(const Connection &lhs, const Connection &rhs) noexcept
compare for equality
Definition: connection.hpp:78
std::function< void()> DisconnectFunction
Definition: connection.hpp:31
bool isConnected() const noexcept
check if connected to the signal
Definition: connection.hpp:54