Page 82 - DCAP404 _Object Oriented Programming

Unit 4: Classes and Objects

second two; Notes
int sum()
//error, scope of the member function is not defined
{
return (x+y);
}
Both classes in the above case are defined with the same member function names. While accessing
these member function, it gives an error. The scope of the member function sum( ) is not defined.
When accessing the member function sum( ), control will be transferred to both classes one and
two. So the scope resolution operator (::) is absolutely necessary for defining the member
functions outside the class declaration.

int one:: sum( ) // correct
{
return (x+y);
}

Self Assessment

Fill in the blanks:
6. Member functions is only declared inside the class but …………………… outside the class.

7. The type of member function arguments must exactly match with the types declared in
the……………………. .
8. Only …………………….. identifies the function as a member of a particular class.

9. Without this scope operator, the function definition would create an ordinary function,
subject to the usual function rules to access an……………….. .

4.3 Creating Class Objects

Objects are the basic run-time entities in an object-oriented system. They may represent a person,
a place, a bank account, a table of data; they may also represent user-defined data such as vectors,
time and lists.

Figure 4.2: Example of an Object

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