9. Function default parameters

• C++ functions can have default parameters:

  
      void print( int value, int base = 10 );
  
      void f()
      {
          print( 31 );     // uses default
          print( 31, 8 );  // overrides default
          print( 31, 10 ); // same as first call
      }
  
  

• Same as

  
      void print( int value, int base );
      void print( int value ) { print( value, 10 ); }
  
  

• But only trailing arguments can be defaulted:

  
      void func_one( int x, int y = 0 ); // Ok
      void func_two( int x = 0, int y ); // Error!