Mastering C++ Programming

Circular dependency

Circular dependency is an issue that occurs if object A depends on B, and object B depends on A. Now let's see how this issue could be fixed with a combination of shared_ptr and weak_ptr, eventually breaking the circular dependency, as follows:

#include <iostream>#include <string>#include <memory>#include <sstream>using namespace std;class C;class A {      private:           weak_ptr<C> ptr;      public:           A() {                  cout << "\nA constructor" << endl;           }           ~A() {                  cout << "\nA destructor" << endl;           }           void setObject ( weak_ptr<C> ptr ) {                  this->ptr = ptr;           }};class B {      private:           weak_ptr<C> ptr;      public:           B() {               cout << "\nB constructor" << endl;           }                      ~B() {               cout << "\nB destructor" << endl;           }           void setObject ( weak_ptr<C> ptr ) {                this->ptr = ptr;           }};class C { ...