C++17 STL Cookbook

How to do it...

We are going to write a program that is similar to the program we wrote in the unique_ptr recipe in order to get insights into the usage and principles of shared_ptr:

1. At first, we just include the necessary headers and declare that we use the std namespace by default:

      #include <iostream>      #include <memory>            using namespace std;

2. Then we define a little helper class, which helps us see when instances of it are actually created and destroyed. We will manage instances of it with shared_ptr:

      class Foo      {      public:          string name;                Foo(string n)              : name{move(n)}          { cout << "CTOR " << name << '\n'; }                ~Foo() { cout << "DTOR " << name << '\n'; }      };

3. Next, we implement a function that takes a shared pointer to a Foo instance by value ...