List * prescriptions; // List is a test header, but ihats not where the problem is

void loop_prescriptions ();
typedef void (*cb_prescription)(Prescription * prescription); // the problem starts here

int main ()
{
  char * name = new char[6];
  strcpy(name, "abcdef");

    prescriptions = new List(Sorted); //creates an empty list, but lets say there are some elements
  Prescription * paper = new Prescription(); //has method hasPatient, which compares to char arrays and returns boolean

  loop_prescriptions ([&] (Prescription * paper) { //and somewhere in here
    if (paper->hasPatient(name)) {
        paper->display();
    }
  });


  return 0;
}



void loop_prescriptions (cb_prescription callback, bool add = true)
{
  //loop through all the elements
    for (int i = 1; i <= prescriptions->noOfElements(); i++) {
      //get the element and send it to callback for usage
        Prescription * prescription = (Prescription *) prescriptions->removeNo(i); //removeNo, returns a pointer to the prescription class (Prescription *)
        if (add) { //since the element has been removed, it should be readded unless the developer says so
            prescriptions->add(prescription);
        }
        callback(prescription); //return the element
    }
}

/*
error: cannot convert ‘list_prescriptions_by_doctor()::<lambda(Prescription*)>’ to ‘cb_prescription {aka void (*)(Prescription*)}’ for argument ‘1’ to ‘void loop_prescriptions(cb_prescription, bool)’
     });
*/