Online PHP editor | output for Mu7cs

<?php function get_next_colid(string $id): string { $length = \strlen($id); for ($i = $length - 1; $i >= 0; $i--) { if ($id[$i] === "\xff") { $id[$i] = "\0"; continue; } $id[$i] = \chr(\ord($id[$i]) + 1); return $id; } return str_repeat("\0", $length + 1); } var_dump( get_next_colid(get_next_colid('{')), get_next_colid(get_next_colid('<')), get_next_colid(get_next_colid('[')), get_next_colid(get_next_colid('(')), );