Mixed¶
A special type that represents any available type. It is equivalent to not explicitly setting the type, though it is now explicitly done.
A mixed type may be also represented by a union of all possible types.
mixed is useful when literally any type should be supported, such as with a cache system. Yet, it is usually recommended to consider reducing the number of possible types by using a common interface or a union type.
<?php
function cache(string $name, mixed $value) : bool {
static $cache = [];
$cache[$name] = $value;
return true;
}
?>
See also Mixed Type PHP 8 and A mixed type PHPStan journey.
Related : Type System, Pseudo-type, Special Types, Type Inference, Wildcard
Added in PHP 8.0+
