Note that an empty input string will still result in one element in the output array. This is something to remember when you are processing unknown input.
For example, maybe you are splitting part of a URI by forward slashes (like "articles/42/show" => ["articles", "42", "show"]). And maybe you expect that an empty URI will result in an empty array ("" => []). Instead, it will contain one element, with an empty string:
<?php
$uri = '';
$parts = explode('/', $uri));
var_dump($parts);
?>
Will output:
array(1) {
[0]=>
string(0) ""
}
And not:
array(0) {
}