GuiKitWidget2.cpp: In member function âvoid HostedSubscriber<Host, Delivery, Cancellation>::OnDelivery()â:
GuiKitWidget2.cpp:53: error: âhost_â was not declared in this scope
GuiKitWidget2.cpp: In member function âvoid HostedSubscriber<Host, Delivery, Cancellation>::OnCancellation()â:
GuiKitWidget2.cpp:57: error: âsubscribable_â was not declared in this scope
GuiKitWidget2.cpp:58: error: âhost_â was not declared in this scope
GuiKitWidget2.cpp: In member function âvoid HostedSubscriberDeliveryOnly<Host, Delivery>::OnDelivery()â:
GuiKitWidget2.cpp:70: error: âhost_â was not declared in this scope
GuiKitWidget2.cpp: In member function âvoid HostedSubscriberDeliveryOnly<Host, Delivery>::OnCancellation()â:
GuiKitWidget2.cpp:74: error: âsubscribable_â was not declared in this scope
GuiKitWidget2.cpp:75: error: âhost_â was not declared in this scope
GuiKitWidget2.cpp: In member function âvoid HostedSubscriberCancellationOnly<Host, Cancellation>::OnCancellation()â:
GuiKitWidget2.cpp:88: error: âsubscribable_â was not declared in this scope
GuiKitWidget2.cpp:89: error: âhost_â was not declared in this scope

class Subscriber
{
  public:
    virtual void OnDelivery() = 0;
    virtual void OnCancellation() = 0;
};

class Subscribable
{
  public:
    virtual void AddSubscriber(Subscriber *sub) = 0;
    virtual void RemoveSubscriber(Subscriber *sub) = 0;
};

template<typename Host>
class HostedSubscriberBase : Subscriber
{
  public:
    HostedSubscriberBase() : host_(0), subscribable_(0) {}
    void Start(Subscribable *sub, Host *host)
      {
        Stop();
        if (sub != 0)
        {
          host_ = host;
          subscribable_ = sub;
          sub->AddSubscriber(this);
        }
      }
    void Stop()
      {
        if (subscribable_)
          subscribable_->RemoveSubscriber(this);
        subscribable_ = 0;
        host_ = 0;
      }
    bool Active() const
      {
        return subscribable_ != 0;
      }
  protected:
    Host *host_;
    Subscribable * subscribable_;
};

template<typename Host, void (Host::*Delivery)(), void (Host::*Cancellation)()>
class HostedSubscriber : public HostedSubscriberBase<Host>
{
  public:
    void OnDelivery()
      {
        host_->Delivery();
      }
    void OnCancellation()
      {
        subscribable_ = 0;
        Host *h = host_;
        host_ = 0;
        (h->*Cancellation)();
      }
};

template<typename Host, void (Host::*Delivery)()>
class HostedSubscriberDeliveryOnly : public HostedSubscriberBase<Host>
{
  public:
    void OnDelivery()
      {
        host_->OnDelivery();
      }
    void OnCancellation()
      {
        subscribable_ = 0;
        host_ = 0;
      }
};

template<typename Host, void (Host::*Cancellation)()>
class HostedSubscriberCancellationOnly : public HostedSubscriberBase<Host>
{
  public:
    void OnDelivery()
      {
      }
    void OnCancellation()
      {
        subscribable_ = 0;
        Host *h = host_;
        host_ = 0;
        (h->*Cancellation)();
      }
};

class Foo
{
  public:
    void Func() {}
    HostedSubscriberCancellationOnly<Foo, &Foo::Func> foo_;
};

protected:    typename Host *host_;    typename Subscribable * subscribable_;