C++ pass argument to singleton

class Questionnary
{
  std::string _str;

  static Questionnary& getInstanceImpl(std::string* const s = nullptr)
  {
    static Questionnary instance{ s };
    return instance;
  }

  Questionnary(std::string* const s)
    : _str{ s ? move(*s) : std::string{} } // employ move ctor
  {
    if (nullptr == s)
      throw std::runtime_error{ "Questionnary not initialized" };
  }

public:
  static Questionnary& getInstance()
  {
    return getInstanceImpl();
  }
  static void init(std::string s) // enable moving in
  {
    getInstanceImpl(&s);
  }

  Questionnary(Questionnary const&) = delete;
  void operator=(Questionnary const&) = delete;
};

Source: stackoverflow.com

Similar codes

0 vote131 views1 answer
Dijkstra algorithm in c++ geeksforgeeks
C++
1 vote99 views2 answers
Calling by reference c++
C++
29 votes85 views2 answers
C program runner
C++
0 vote113 views1 answer
Adding variables c++
C++
0 vote113 views1 answer
Getline(cin string) not working
C++
10 votes97 views3 answers
Initialise 2d vector in c++
C++
1 vote109 views1 answer
Chess perft 5
C++
0 vote91 views1 answer
How to turn an integer variable into a char c++
C++
4 votes100 views2 answers
C++ stream string into fiel
C++
0 vote93 views1 answer
How do I read computer current time in c++
C++