Signal.hpp

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#ifndef DART_COMMON_SIGNAL_HPP_
#define DART_COMMON_SIGNAL_HPP_

#include <functional>
#include <memory>
#include <set>

#include "dart/common/Deprecated.hpp"
#include "dart/common/detail/ConnectionBody.hpp"

namespace dart {
namespace common {

class Connection
{
public:
  Connection();

  Connection(const Connection& _other);

  Connection(Connection&& _other);

  Connection& operator=(const Connection& _other);

  Connection& operator=(Connection&& _other);

  virtual ~Connection();

  bool isConnected() const;

  void disconnect() const;
  // TODO(JS): Make this non-const in the next major release

  template <typename _Signature, template <class> class Combiner>
  friend class Signal;

protected:
  Connection(
      const std::weak_ptr<signal::detail::ConnectionBodyBase>& _connectionBody);

  Connection(
      std::weak_ptr<signal::detail::ConnectionBodyBase>&& _connectionBody);

private:
  std::weak_ptr<signal::detail::ConnectionBodyBase> mWeakConnectionBody;
};

class ScopedConnection : public Connection
{
public:
  ScopedConnection(const Connection& _other);

  ScopedConnection(Connection&& _other);

  virtual ~ScopedConnection();
};

template <
    typename _Signature,
    template <class> class Combiner = signal::detail::DefaultCombiner>
class Signal;

template <typename _Res, typename... _ArgTypes, template <class> class Combiner>
class Signal<_Res(_ArgTypes...), Combiner>
{
public:
  using ResultType = _Res;
  using SlotType = std::function<ResultType(_ArgTypes...)>;
  using SignalType = Signal<_Res(_ArgTypes...), Combiner>;

  using ConnectionBodyType = signal::detail::ConnectionBody<Signal>;
  using ConnectionSetType = std::set<
      std::shared_ptr<ConnectionBodyType>,
      std::owner_less<std::shared_ptr<ConnectionBodyType>>>;

  Signal();

  virtual ~Signal();

  Connection connect(const SlotType& _slot);

  Connection connect(SlotType&& _slot);

  void disconnect(const Connection& _connection) const;

  void disconnect(const std::shared_ptr<ConnectionBodyType>& connectionBody);

  void disconnectAll();

  DART_DEPRECATED(6.10)
  void cleanupConnections();
  // This explicit connection cleaning is no longer necessary because now a
  // connection gets removed when it's disconnected.

  std::size_t getNumConnections() const;

  template <typename... ArgTypes>
  ResultType raise(ArgTypes&&... _args);

  template <typename... ArgTypes>
  ResultType operator()(ArgTypes&&... _args);

private:
  ConnectionSetType mConnectionBodies;
};

template <typename... _ArgTypes>
class Signal<void(_ArgTypes...)>
{
public:
  using SlotType = std::function<void(_ArgTypes...)>;
  using SignalType = Signal<void(_ArgTypes...)>;

  using ConnectionBodyType = signal::detail::ConnectionBody<Signal>;
  using ConnectionSetType = std::set<
      std::shared_ptr<ConnectionBodyType>,
      std::owner_less<std::shared_ptr<ConnectionBodyType>>>;

  Signal();

  virtual ~Signal();

  Connection connect(const SlotType& _slot);

  Connection connect(SlotType&& _slot);

  void disconnect(const Connection& _connection) const;

  void disconnect(const std::shared_ptr<ConnectionBodyType>& connectionBody);

  void disconnectAll();

  DART_DEPRECATED(6.10)
  void cleanupConnections();
  // This explicit connection cleaning is no longer necessary because now a
  // connection gets removed when it's disconnected.

  std::size_t getNumConnections() const;

  template <typename... ArgTypes>
  void raise(ArgTypes&&... _args);

  template <typename... ArgTypes>
  void operator()(ArgTypes&&... _args);

private:
  ConnectionSetType mConnectionBodies;
};

template <typename T>
class SlotRegister
{
public:
  using SlotType = typename T::SlotType;
  using SignalType = typename T::SignalType;

  SlotRegister(typename T::SignalType& _signal);

  Connection connect(const SlotType& _slot);

private:
  typename T::SignalType& mSignal;
};

} // namespace common
} // namespace dart

#include "dart/common/detail/Signal.hpp"

#endif // DART_COMMON_SIGNAL_HPP_