Can I use std::make_shared with structs that don't have a parametric constructor?

Question

Say I have a struct like this:

struct S
{
int i;
double d;
std::string s;
};

Can I do this?

std::make_shared<S>(1, 2.1, "Hello")

Answer 1

No you can't, you have to define your own constructor for being able to do it.

#include <iostream>
#include <memory>
#include <string>

struct S
{
    S(int ii, double dd)
    : i(ii)
    , d(dd)
    { }
  int i;
  double d;
};

int main()
{
 // S s{1, 2.1};
  auto s = std::make_shared<S>(1, 2.1);
  //or without constructor, you have to create manually a temporary
  auto s1 = std::make_shared<S>(S{1, 2.1});

}