Software Engineering and Computer Games

22.2. Implicit arguments

Suppose that SomeClass is a class whose prototype includes a member _val and two functions SomeFunction and SomeOtherFunction.

class SomeClass 
{ 
    int _val; 
    int ValSquared(){return _val * _val;} 
    int SomeFunction(int input); 
    int SomeOtherFunction(int first, int second); 
}; 

Now if K is an object of type SomeClass, then the value of, let us say, K.SomeFunction(17)will depend on (a) the argument 17, (b) the function definition of SomeFunction, and (c) the contents of the object K. K is an ‘implicit argument’ to this function call.

When you write out the code for SomeFunction, you play on the fact that you have an implicit argument to the function, even though you don’t explicitly show it. Thus the code for SomeFunction