What is the practical use of pointers to member functions?

Question

I\'ve read through this article, and what I take from it is that when you want to call a pointer to a member function, you need an instance (either a pointer to one or a sta

Answer 1

Member pointers + templates = pure win.

e.g. How to tell if class contains a certain member function in compile time

or

template
TProperty grand_total(TContainer& items, TProperty (TElement::*property)() const)
{
   TProperty accum = 0;
   for( auto it = items.begin(), end = items.end(); it != end; ++it) {
       accum += (it->*property)();
   }
   return accum;
}

auto ship_count = grand_total(invoice->lineItems, &LineItem::get_quantity);
auto sub_total = grand_total(invoice->lineItems, &LineItem::get_extended_total);
auto sales_tax = grand_total(invoice->lineItems, &LineItem::calculate_tax);