Question

(True/False) In C++, only existing operators can be overloaded.

Short answer

True, only existing operators can be overloaded in C++.

Step-by-step solution

Understanding Operator Overloading

In C++, operators such as +, -, *, etc., can be given additional meanings when used with user-defined data types. This process is known as operator overloading. The key point is that only existing operators can be overloaded, meaning you cannot create new operators that do not already exist in the language.

Identifying Existing Operators

Operators that are predefined in C++ include arithmetic operators (+, -, *, /), relational operators (==, !=, >, <), and logical operators (&&, ||, !), among others. These operators have specific syntactic symbols provided by the C++ language.

Checking for New Operator Creation

C++ does not allow the creation of new operators. You can only redefine or overload existing ones to work with user-defined types. This restriction means programmers can enhance operators' functionalities but cannot invent completely new operator symbols.

Determining the Truth of the Statement

Given the understanding that only existing operators can be overloaded and no new operators can be created in C++, the statement "only existing operators can be overloaded" is true.

Key concepts

Existing Operators

In C++, operators such as +, -, *, and / are predefined and commonly used for performing arithmetic operations. These are known as existing operators. The language has a multitude of operators that handle various tasks, such as arithmetic and relational comparisons.

Existing operators also include relational operators like == and !=, which compare values, as well as logical operators such as && and ||, used in logical operations to evaluate expressions. These operators are well known and widely implemented in the syntax of C++.

The ability to overload these operators allows developers to extend their functionality when they are used with user-defined data types, making them versatile tools in programming.

User-Defined Data Types

User-defined data types, such as classes and structs, are a fundamental component of C++. They allow programmers to create complex data structures tailored to their specific needs.

For instance, you can define a class to represent complex numbers, which then can have operations like addition and subtraction performed on them. However, out of the box, C++ does not know how to handle these operations for a new class you defined, because operators like + or - work naturally on built-in data types like int or float. To enable such operations, you use operator overloading. By overloading operators, user-defined data types can seamlessly interact using C++'s built-in syntactic constructs, which makes the code more intuitive and readable.

Restriction on New Operators

C++ imposes a restriction that no new operators can be created. This might seem limiting, but it ensures that the language maintains uniformity and does not become cluttered with unfamiliar symbols.

This restriction means you can redefine the behavior of existing operators when they interact with user-defined data types, but you cannot invent new operator symbols. Essentially, you work within the set framework of C++ to enhance the language's capabilities without altering its foundational syntax.

By enforcing the rule of no new operators, C++ encourages developers to stay within the bounds of a shared language construct, facilitating clearer communication across projects.

C++ Language Syntax

Understanding C++ language syntax is crucial when working with operator overloading. Operator overloading follows specific syntactical rules. These rules ensure that any operator you overload has the same precedence and associativity as the original operator.

The syntax for operator overloading involves defining a function with the keyword `operator` followed by the operator symbol, e.g., `operator+`. This function is then defined within the class of the user-defined data type whose objects are meant to utilize the operator.

C++ syntax ensures consistency by making certain that overloaded operators behave in a predictable manner. Following these syntactic rules helps to maintain the clarity and robustness of the code, as the overloaded operators integrate smoothly into the existing framework of the language.