Interfaces may not include properties

Description

Interfaces can define methods and constants, but they can’t define properties. Actually, they can only define properties with a property hook, as the property hooks are methods.

Example

<?php

interface I {
     private $property;
}

?>

Solutions

• Upgrade PHP version to 8.4.

• Turn the interface in an abstract class.

• Turn the interface in a trait.

• Add a property hook to a property.

In previous PHP versions, this error message used to be Interfaces may only include hooked properties.