PHP中的参数提示

PHP为了解决自己是弱类型语言在调用方法是传参类型可能导致的问题,引入了参数提示,看代码

 1 <html>
 2      <body>
 3          <?php
 4             class Man {
 5                 private $name;
 6                 
 7                 function getName() {
 8                     return $this->name;
 9                 }
10                 
11                 function setName($name) {
12                     $this->name = $name;
13                 }
14             }
15 
16             class Wrong {}
17             
18             function callMan(Man $man) {
19                 echo "Hey " . $man->getName();
20             }
21             
22             $man = new Man();
23             $man->setName('Jack');
24             
25             callMan($man);
26             callMan(new Wrong());
27          ?>
28      </body>
29  </html>

再看输出

Hey Jack
Catchable fatal error: Argument 1 passed to callMan() must be an instance of Man, instance of Wrong given, called in D:\www\index.php on line 26 and defined in D:\www\index.php on line 18

由于callMan()函数传入参数类型不是Man,导致了catchable fatal error,至此我觉得PHP慢慢变得自相矛盾,许多自己的特性给自己造成了困扰,然后又出新特性来解决原来的问题