c++ - Is there a way to overload operator= to have specific behavior for a function on right hand side -

i have class named image non member function return image.

image::image(const char * src); image::image& operator= (const image& p); image requestimg(std::string filename); //not member function 

and use so:

image p = requestimg("grass.png"); 

this fine, however- able have requestimg spawn thread loads image image object(p), while modifying object have status of loading=true.

in other words.

image p = requestimg("grass.png");  //image loading std::cout << p.loading << std::endl; //true //some time passes std::cout << p.loading << std::endl; //false 

p cannot have loading set true initially, not loading , not lead sane naming. realize member function easier- or passing pointer function, there way i've laid out?

you can leave image is, , use std::async, give std::future<image>. can decide when need result of that:

#include <future>  auto p = std::async(std::launch::async, &requestimg,"grass.png"); // load image asynchronously //some time passes // other work  // need image auto img = p.get(); // blocking call, requires async call done loading image.