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

Modify your code here:

public:
    void add(string x, string y, int val);
    vector filter(string s, string (Row::*)() const);
private:
    ...

Here:

vector Table::filter(string s, string (Row::*f)() const)
{   
    vector result;
    vector::iterator it;
    for(it = d_table.begin(); it != d_table.end(); ++it) {
        if((*it.*f)() == s) {
            int val = it->getVal();
            result.push_back(val); 
        }
    }
    return result;
}

And here:

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

    ...