Language: C C++ D Haskell Lua OCaml PHP Perl Plain Text Python Ruby Scheme Tcl class ControlConfig { public: static ControlConfig &instance(); virtual void op1 = 0; protected : ControlConfig(); virtual ~ControlConfig(); private : //member object ControlConfig. * syntex of reference Class object. static ControlConfig *instance_; //member data friend class Destroyer; }; //initialize parameter ControlConfig *ControlConfig::instance_ = 0; //main idea for create only one instace for config ControlConfig::instance(){ if( ! = instance_ ){ instance_ = new ControlDataOne(); } return *instance_; } ControlConfig::ControlConfig() { std::cout<<"Create Object"<<std::endl; } ControlConfig::~ControlConfig() { std::cout<<"Destroyer Object"<<std::endl; } //destroyer instance class Destroyer{ public : ~Destroyer(){ delete ControlConfig::instance_; } } //create namespace namespace{ Destroyer d; } //concept by C++ Gotchas Private [?] Run code