Online PHP editor | refs for gc4Ye

<?php class ToStringMadness { private $data; public function __construct($data) { $this->data = $data; } public function __toString() { //$data = array_map(function($item) { return $item; }, $this->data); $data = array_merge($this->data); sort($data); $rs = implode('-', $data); echo $rs."\n"; return $rs; } } $a = [ new ToStringMadness(['c','b']), new ToStringMadness(['c','b','a']), new ToStringMadness(['a','b']), ]; sort($a); print_r($a); usort($a, function(ToStringMadness $itemA, ToStringMadness $itemB) { return strcmp((string)$itemA, (string)$itemB); }); print_r($a);