Question

I vaguely remember that it was possible to write something like:

void f(int a, int b=0, bool c=!val);

if some extra stuff was written at the beginning of the arguments list. The example in GCC gives error of val non declared in scope.
Unfortunately, I cannot find any reference on the Internet, so I ask here.

Answer 1

How about overloading f()? It won’t be a problem whether val is const or not.

void f(int a, int b, bool c);

void f(int a, int b=0) {
   f(a,b,!val);
}