Operator (computer programming)

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Operator" computer programming – news · newspapers · books · scholar · JSTOR (January 2019) (Learn how and when to remove this message)

In computer programming, an operator is a programming language construct that provides functionality that may not be possible to define as a user-defined function (i.e. sizeof in C) or has syntax different than a function (i.e. infix addition as in a+b). Like other programming language concepts, operator has a generally accepted, although debatable meaning among practitioners while at the same time each language gives it specific meaning in that context, and therefore the meaning varies by language.

Some operators are represented with symbols – characters typically not allowed for a function identifier – to allow for presentation that is more familiar looking than typical function syntax. For example, a function that tests for greater-than could be named gt, but many languages provide an infix symbolic operator so that code looks more familiar. For example, this:

if gt(x, y) then return

Can be:

if x > y then return

Some languages allow a language-defined operator to be overridden with user-defined behavior and some allow for user-defined operator symbols.

Operators may also differ semantically from functions. For example, short-circuit Boolean operations evaluate later arguments only if earlier ones are not false.