3v4l.org

run code in 300+ PHP versions simultaneously
<?php class O implements ArrayAccess { public function offsetSet($key, $value) { $this->data[$key] = $value; } public function offsetExists($key) { return isset($this->data[$key]); } public function offsetUnset($key) { unset($this->data[$key]); } public function offsetGet($key) { return $this->data[$key]; } } $o = new O; $o['foo'] = 'bar'; var_dump(array_key_exists('foo', $o)); var_dump(array_key_exists('bar', $o)); $a = array(); $a['foo'] = 'bar'; var_dump(array_key_exists('foo', $a)); var_dump(array_key_exists('bar', $a));

preferences:
53.35 ms | 402 KiB | 5 Q