c++ - Call function with all instances of a struct -

i want call function struct objects.

i need function can loop through struct-objects a_1, a_2 calling struct struct_a. empty function 'reset_all_structs( ??? )' @ bottom of code.

sample code:

#include <iostream>   struct struct_a {     unsigned char number = 0;     bool bool_1 = 0;     bool bool_2 = 0; } a_1, a_2; // objects: maybe later a_3, ... , a_x  void print_to_terminal(struct_a &struct_name); void set_bool_1(struct_a &struct_name); void set_bool_2(struct_a &struct_name); void reset_one_struct(struct_a &struct_name); void reset_all_structs();  int main() {      set_bool_1(a_1);     a_1.number = 111;     set_bool_2(a_2);     a_2.number = 222;     std::cout << "a_1:\n";     print_to_terminal(a_1);     std::cout << "\n";     std::cout << "a_2:\n";     print_to_terminal(a_2);     std::cout << "\n";      reset_one_struct(a_1); // <-- reset 1 struct works, question ist how reset structs type struct_a?     std::cout << "a_1:\n";     print_to_terminal(a_1);     std::cout << "\n";      set_bool_2(a_1);     a_1.number = 234;     std::cout << "a_1:\n";     print_to_terminal(a_1);     std::cout << "\n";      // here question. ???      // reset_all_structs( struct_a );      // want reset both a_1 , a_2 calling function reset_all_structs object of struct "struct_a" , loop through these. possible     // don't want call function reset_all_struct(a_1, a_2) because later add more objects of struct struct_a.      std::cout << "reset a_1 , a_2\n";     std::cout << "a_1:\n";     print_to_terminal(a_1);     std::cout << "\n";     std::cout << "a_2:\n";     print_to_terminal(a_2);     std::cout << "\n";       return 0; }  void print_to_terminal(struct_a &struct_name){     std::cout << "number: " << (int)struct_name.number << "\n";     std::cout << "bool_1: " << (int)struct_name.bool_1 << "\n";     std::cout << "bool_2: " << (int)struct_name.bool_2 << "\n";     return; };  void set_bool_1(struct_a &struct_name){     struct_name.bool_1 = 1;     struct_name.bool_2 = 0;     return; };  void set_bool_2(struct_a &struct_name){     struct_name.bool_1 = 0;     struct_name.bool_2 = 1;     return; };  void reset_one_struct(struct_a &struct_name){     struct_name.number = 0;     struct_name.bool_1 = 0;     struct_name.bool_2 = 0;     return; };   void reset_all_structs( ??? ){ // loop through structs     return; }; 

the language doesn't have possibility iterate through same variables of same types.

you can make sort of registry of structs , iterate through registry. like:

struct struct_a; std::vector<struct_a*> struct_a_registry;  struct struct_a {    ...    // constructor    struct_a() { struct_a_registry.push_back(this); }    // destructor    ~struct_a() {        (std::vector<struct_a*>::iterator = struct_a_registry.begin();             != struct_a_registry.end(); ++it)          if (*it == this) {           struct_a_registry.erase(this);           break;         }     } }; 

then reset_all_structs just

void reset_all_structs() {   (std::vector<struct_a*>::iterator = struct_a_registry.begin();         != struct_a_registry.end(); ++it)      reset_one_struct(**it); } 

or, if declaring struct_a variables @ same line of program, can organize them array, simpler.