Create a constructor for a shared_ptr<MyClass> - c++

Question

#include <iostream>
#include <vector>
class TestX {
public:
int i;
TestX(int inp1) : i(inp1){}
};
using Test = std::shared_ptr<TestX>;
int main()
{
Test a(4);
std::cout << a->i << std::endl;
}
I wanted to hide away that I am using a shared pointer, and make it look like I have just a regular class. The reason is that it is essential that my objects are never copied, but I still want the users to be able to create a vector with {obj1, obj2}. Is there a way to initialize a Test object as if there was a constructor, or do I have to use make_shared to initialize it?

Answer 1

You can use a class to wrap a std::shared_ptr, as follows
#include <iostream>
#include <vector>
#include <memory>
struct TestX {
int i;
TestX(int inp1) : i(inp1){}
TestX(TestX const &) = delete;
};
struct Test {
std::shared_ptr<TestX>test;
Test(int inp1) : test{std::make_shared<TestX>(inp1)}{}
int& get_i (){
return test -> i;
}
};
int main()
{
Test a(4);
Test b(1);
auto v = std::vector{a, b};
std::cout << a.get_i() << std::endl;
}

Answer 2

you can also derive from shared_ptr<TestX>
#include <iostream>
#include <vector>
#include <memory>
class TestX {
public:
int i;
TestX(int inp1) : i(inp1){}
};
struct Test : std::shared_ptr<TestX>{
Test( int x) : std::shared_ptr<TestX>{std::make_shared<TestX>(x)}{}
};
int main()
{
Test a(4);
std::cout << a->i << std::endl;
Test b(1);
auto v = std::vector{a, b};
}