If the array has non-numerical keys, array_shift extracts the first element, whichever is the key, and recompute the numerical keys, if there are any. Ie :
$array = array("c" => "ccc", 0 => "aaa", "d" => "ddd", 5 => "bbb");
$first = array_shift($array);
echo '$first = ' . $first . ', $array = ' . var_export($array, true);
will display :
$first = ccc, $array = array ( 0 => 'aaa', 'd' => 'ddd', 1 => 'bbb', )
It means that array_shift works with associative arrays too, and leaves the keys unchanged if they are non-numerical.
