php 接口继承接口

<?php
interface User 
{ 
function getName(); 
function setName($_name); 
} 
interface VipUser extends User //VipUser继承User接口
{ 
function getDiscount(); //此处添加了一个抽象的方法 
} 
class Vip implements VipUser 
{ 
private $name; 
private $discount = 0.8; //折扣变量 
function getName() { 
return $this->name; 
} 
function setName($_name) { 
$this->name = $_name; 
} 
function getDiscount() { 
return $this->discount; 
} 
} 

$v = new Vip;
echo $v->getDiscount();