簡易的なタスクシステムの試作

pod_system.cpp

#include <iostream>
#include <string>


template<class T> class Pod {
protected:
	virtual void OnReceive(T msg) {}

	void Send(T msg) {
		Pod<T>* x = this;
		while((x = x->Next()) && x != this){
			x->OnReceive(msg);
		}
	}

public:
	virtual ~Pod() {}

	virtual Pod* Next() = 0;

	virtual void Update() = 0;

	void Loop() {
		Pod<T>* x = this;
		do{
			x->Update();
		}while(x = x->Next());
	}
};


template<class T> class SimplePod : public Pod<T> {
protected:
	Pod<T>* next;

public:
	SimplePod(Pod<T>* next) : next(next) {}

	SimplePod() : next(NULL) {}

	virtual ~SimplePod() {}

	void SetNext(Pod<T>* next) {
		this->next = next;
	}

	virtual Pod<T>* Next() {
		return next;
	}
};


class NamedPod : public SimplePod<std::string> {
private:
	std::string name;

public:
	NamedPod(std::string name, Pod<std::string>* next) : SimplePod<std::string>(next), name(name) {}

	NamedPod(std::string name) : name(name) {}

	virtual void OnReceive(std::string msg) {
		std::cout << name << ": " << msg << std::endl;
	}

	virtual void Update() {
		std::cout << name << std::endl;

		Send(std::string("hello by ") + name);
	}
};


template<class T> class EndOfPods : public Pod<T> {
public:
	virtual Pod<T>* Next() {
		return NULL;
	}

	virtual void Update() {}
};


int main() {
	NamedPod c("tec"), b("teb", &c), a("tea", &b);

	c.SetNext(&a);

	a.Loop();
}