Online PHP editor | refs for 3Z0f7

<?php class MyCache { private $cache = []; public function has($key) { echo "\nget: " . json_encode($key); return array_key_exists( $key, $this->cache ); } public function set($key, $val) { echo "\nset: " . json_encode($key); $this->cache[$key] = $val; } } $mc = new MyCache(); $mc->has(['x']); $mc->has([]); $mc->has(false); $mc->has(true); $mc->has(''); $mc->has(0); echo "\n"; $mc->set(['x'], 1); $mc->set([], 1); $mc->set(false, 1); $mc->set(true, 1); $mc->set('', 1); $mc->set(0, 1);