?: Elvis Operator

Returns the right operand if the left operand is falsy (expression)

Description

The Elvis Operator is a little like a conditional where the result of the operation is the first non-falsy value from left to right.

A falsy value is any of the following:

Examples

Assign with a default value

» $foo = $bar ?: "baz"

If $bar is falsy, then the value of $foo will be “baz”.

Multiple elvis operators

» $unset_variable ?: null ?: false ?: "foobar"
foobar

Detail

Whats in a name?

Wikipedia explains this best where it says:

The name “Elvis operator” refers to the fact that when its common notation, ?:, is viewed sideways, it resembles an emoticon of Elvis Presley with his signature hairstyle.

See Also


This document was generated from gen/expr/elvis-op_doc.yaml.

This site's content is rebuilt automatically from murex's source code after each merge to the master branch. Downloadable murex binaries are also built with the website.

Last built on Wed Jul 2 22:12:32 UTC 2025 against commit bb72b6fbb72b6fdd502f835172d7d06207ba4ec2c70886c.

Current version is 7.0.2107 (develop) which has been verified against tests cases.