Variadic Are Typed And Defaulted

<?php

function foo($a, ...$arg /* = [] */) {
    var_dump($arg);
    // array()
}

foo(1);

?>

When using the ... operator, the argument is automatically typed and defaulted: it is typed with array, and its default value is the empty array [].

There can be a type added to the argument, and, with it, element element of the argument will be of this type. Yet, the argument itself is actually array.

See Also

• Type declarations (PHP manual)

• Hidden type and default value [Try me]

PHP Features

• array

• variadic

• type

• default

Last updated: 14 July 2026