PHP7新特性—匿名类

http://www.runoob.com/php/php-anonymous-classes.html

PHP 7 支持通过 new class 来实例化一个匿名类，这可以用来替代一些 “ 用后即焚 ” 的完整类定义

interface Logger
{
    public function log(String $msg);
}
class Application
{
    private $logger;
    public function getLogger(): Logger
    {
        return $this->logger;
    }
    public function setLogger(Logger $logger){
        $this->logger = $logger;
    }
}
$app = new Application();
$app->setLogger(new class implements Logger{
    public function log(String $msg)
    {
        print($msg);
    }
});
$app->getLogger()->log('hello zzh!');