What is operator overloading

Operator overloading is helpful in cases where the operators used for certain types provide semantics related to the domain context and syntactic support as found in the programming language. It is used for syntactical convenience, readability and maintainability.

Operators are referenced using operator notation in expressions and functional notation in declarations. The syntax, precedence and associativity of an operator cannot be changed by using user-defined operator declarations.

For example, operators in C are categorized based on the type of operation they perform. Some of them are overloaded in user-defined types by defining them in static member functions and using the operator keyword. The parameters of the operator function represent the operands, while the return type of an operator function represents the result of the operation. The Equals method for these operators should be overridden to avoid a compiler warning.

Overloading is not to be used for operators such as conditional, logical and!! It is highly recommended that operator overloading be implemented such that the results produced are what are intuitively expected out of the default implementation of the operator.

Certain mathematical rules such as commutative law, applicable to expressions with two operands, cannot be applicable when used in overloading for types as they are only defined for numerical operands.

By: Justin Stoltzfus Contributor, Reviewer. The canonical implementations usually follow the pattern for binary arithmetic operators described above. The operator operator!

Since the built-in operator! Create account Log in. Namespaces Page Discussion. Views View Edit History. From cppreference. Keywords Escape sequences.

Namespace declaration. Namespace aliases. Fundamental types Enumeration types Function types. Compound types Union types. Default initialization Value initialization Zero initialization Copy initialization Direct initialization. Expressions Value categories Order of evaluation. Operators Operator precedence. Class declaration Constructors this pointer.

Access specifiers friend specifier. Class template Function template. Inline assembly. Run this code. Compiler support. Freestanding and hosted. Language support library. Technical specifications. Flow control. Function declaration.

Lambda function declaration. The constraints on the various categories of overloaded operators are described in the following topics:. Unary Operators. Increment and Decrement.

User-Defined Type Conversions. The operators shown in the following table cannot be overloaded.