singleton.hpp

#pragma once
 
#include <cassert>
 
namespace acheron::ecs {
    template<typename T>
    class SingletonStorage {
        public:
        static void Set(const T& value) {
            instance() = value;
            initialized() = true;
        }

        static T& Get() {
            assert(initialized() && "Singleton not set");
            return instance();
        }

        static bool IsSet() {
            return initialized();
        }
 
        private:
        static T& instance() {
            static T obj;
            return obj;
        }

        static bool& initialized() {
            static bool flag = false;
            return flag;
        }
    };
}