pointer to member function

Question

I am trying to generalize the functions filterX() and filterY() in the following class Table to function filter().

Answer 1

Here is the syntax for the way you want:

vector Table::filter(string s, string (Row::*get)() const)
{                                  //^^^^^^^^^^^^^^^^^^^^^^^^^^^ member pointer
  ...
  if(((*it).*get)() == s) {  // call using the (*it). and not it->
  ... 
}

Call it as:

vector vx = t.filter("x1", &Row::getX);
vector vy = t.filter("y2", &Row::getY);