Advanced C++ Topics

Operator Overloading

Many classes use operators such as ++, * and ==.
Giving a new meaning to an operator is called operator overloading.
You can overload an operator by defining a function whose name is operator followed by the operator symbol.
For example, you can define the difference between two Time objects as the number of seconds between them.
```
int operator-{Time a, Time b)
{
   return a.seconds_from(b);
}
```

Now you can use the - operator instead of calling seconds_from.

Time now;
Time morning(9, 0, 0);
long seconds_elapsed = now - morning;