Running a thread using a variable type of std::function

Question

I would like to launch a std::function type in a separate thread. My code currently looks like this :

struct bar
{
    std::function<void(int,int)> var;
};

struct foo
{
    bar* b;

    foo()
    {
        std::thread t(b->var); //Error attempt to use a deleted function
    }
};

Why am I getting attempt to use a deleted function here ?

Answer 1

Your variable b->var is a function that takes two parameters. You need to send these parameters to make it work.

struct bar
{
  std::function<void(int,int)> var;
};

struct foo
{
   bar* b;
   foo()
   {
      std::thread t(b->var, 76, 89); // will call b->var(76, 89)
   }
};