text: #ifndef SUBJECT_HPP
  #define SUBJECT_HPP
  
  #include "Observer.hpp"
  #include <vector>
  #include <memory>
  
  class Subject {
     public:
      void attach(std::shared_ptr<Observer> observer);
      void notify(const std::any& data, radiostream::Event e);
  
     private:
      std::vector<std::shared_ptr<Observer>> observers_;
  };
  
  #endif
  