PHP兩個類使用同一個命名空間，無法相互調(diào)用

創(chuàng)建了兩個類，C和D，都屬于同一個namespace：func，在D的構(gòu)造函數(shù)中實例化C并調(diào)用C里的cc方法，報找不到func下的C類。

//C.php

<?php
namespace func;

class C {

    public function cc() {

        echo 'this is C->cc';
    }
}

//D.php

<?php
namespace func;

class D {

    public function __construct() {
        $c = new C();
        $c->cc();
    }
}
new D();

執(zhí)行D.php，報錯信息如下：

ClivedeMBP:Workspace clive$ php D.php 
PHP Fatal error:  Uncaught Error: Class 'func\C' not found in /Users/clive/Workspace/D.php:7
Stack trace:
#0 /Users/clive/Workspace/D.php(11): func\D->__construct()
#1 {main}
  thrown in /Users/clive/Workspace/D.php on line 7

Fatal error: Uncaught Error: Class 'func\C' not found in /Users/clive/Workspace/D.php on line 7

Error: Class 'func\C' not found in /Users/clive/Workspace/D.php on line 7

Call Stack:
    0.0010     352608   1. {main}() /Users/clive/Workspace/D.php:0
    0.0029     352648   2. func\D->__construct() /Users/clive/Workspace/D.php:11

請問，同一個命名空間下的兩個類應(yīng)該怎么寫，才能彼此調(diào)用?。?/p>