Chapter 14: Problem 14

Why shouldn't a class's overloaded = operator be implemented with a void operator function?

Short Answer

Expert verified

Answer: Implementing an overloaded assignment operator as a void function in a class would not allow for proper functionality when trying to perform multiple assignments in one statement. This is because the return value of each assignment is necessary for the next assignment to work. The correct implementation should return a reference to the current object, ensuring that the chain of multiple assignments works as expected and adhering to the principle of least astonishment.

Step by step solution

Understanding assignment operator overloading

When overloading assignment operator (=) for a class, we are defining what will happen when objects of that class are assigned to another object. This allows us to have control over how the assignment is performed, especially when class objects have dynamic memory allocation or complex data structures.

Illustrating the problem with void

Consider implementing the overloaded assignment operator as a void function: ```cpp class MyClass { // Other class elements... void operator=(const MyClass &rhs); }; ``` Now, suppose we try to perform multiple assignments in one statement, such as: ```cpp MyClass obj1, obj2, obj3; obj1 = obj2 = obj3; ``` With a void function, the expression 'obj2 = obj3' would not return anything and this chain of multiple assignments would not work, since the return value of each assignment is necessary for the next assignment to work. Thus, implementing the assignment operator as a void function would not allow us to properly perform multiple assignments.

Correct implementation

In order to have the desired behavior, the assignment operator should return a reference to the current object so that the chain of multiple assignments can work correctly: ```cpp class MyClass { // Other class elements... MyClass& operator=(const MyClass &rhs) { // Perform the required assignment steps return *this; } }; ``` Returning a reference to the object itself ensures that the chain of multiple assignments works as expected and allows us to adhere to the principle of least astonishment.

Unlock Step-by-Step Solutions & Ace Your Exams!

Full Textbook Solutions
Get detailed explanations and key concepts
Unlimited Al creation
Al flashcards, explanations, exams and more...
Ads-free access
To over 500 millions flashcards
Money-back guarantee
We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

Recommended explanations on Computer Science Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Why shouldn't a class's overloaded = operator be implemented with a void operator function?

Short Answer

Step by step solution

Understanding assignment operator overloading

Illustrating the problem with void

Correct implementation

One App. One Place for Learning.

Most popular questions from this chapter

Recommended explanations on Computer Science Textbooks

Theory of Computation

Computer Programming

Computer Organisation and Architecture

Big Data

Data Structures

Algorithms in Computer Science

Study anywhere. Anytime. Across all devices.