3. A function object is usually faster than a function pointer.

• 3. A function object is usually faster than a function pointer.

  • 1. Example. Suppose you want to add a certain value to all elements of a collection. If you know the value you want to add at compile time, you could use an ordinary function:
    • void add10 (int& elem)
    • {
    • elem += 10;
    • }
    • void f1( )
    • {
    • vector<int> coll;
    • ...
    • for_each(coll.begin( ), coll.end( ), add10)
    • }