Iterable is a built-in compile time type alias for
array|Traversable.
From its introduction in PHP 7.1.0 and prior to PHP 8.2.0,
iterable was a built-in pseudo-type that acted as the
aforementioned type alias and can be used as a type declaration.
An iterable type can be used in foreach and with
yield from within a
generator.
Note:
Functions declaring iterable as a return type may also be generators.
Example #1 Iterable generator return type example
<?php
function gen(): iterable {
yield 1;
yield 2;
yield 3;
}
?>