ist folgendes legal?

#include <memory>
#include <iostream>
#include <deque>

class Mode {
	public:
		static std::unique_ptr<Mode> current;
		virtual void doSomething() = 0;
};

class B : public Mode {
	public:
		void doSomething() { std::cout << "Mode B " << std::endl; }
};

class A : public Mode {
	private:
		std::deque<char> chars;
	public:
		A() : chars{'a', 'b', 'c'} {}
		void doSomething() { 
			if(chars.empty() ) { 
                Mode::current.reset(new B);
                return;
            }  
			chars.pop_front();
		}
};

std::unique_ptr<Mode> Mode::current(new A);

int main() {
	for(unsigned i = 0; i < 5; ++i) Mode::current->doSomething();
	std::cout << "Done" << std::endl;
}

Du hast nen virtuellen Destruktor in Mode vergessen! Abgesehen davon, ist das alles i.O.

Stimmt, danke.