PHP5.3将加入闭包语法

PHP5.3将加入闭包语法

PHP 5.3 将加入闭包语法，也就是匿名函数，允许开发者申明行内函数和在变量中保存。虽然这个语法和JavaScript的闭包相比有点怪异，但是对于PHP语言来说，这是一个良好的补充。

比如你现在就可以这样使用：

Php代码

1. $closure = function($param) { echo $param; }; 
2.   
3. //This one takes value of someVar and "stores" it in the closure's scope even if 
4. //we later change the value of someVar outside it. We assume that $somerVar is defined before this 
5. $closure2 = function($param) use ($someVar) { echo $param . ' ' . $someVar; }; 

$closure = function($param) { echo $param; };
 
//This one takes value of someVar and "stores" it in the closure's scope even if
//we later change the value of someVar outside it. We assume that $somerVar is defined before this
$closure2 = function($param) use ($someVar) { echo $param . ' ' . $someVar; };

比如在输出HTML中闭包很有用：

Php代码

1. function item_list(array $items, $formatter = null) { 
2.   //create the default formatter 
3.   if($formatter == null) { 
4.     $formatter = function($row) { 
5.       return '

   ' . $row . '

   '; 
6.     }; 
7.   } 
8.   
9.   $html = '

   Listing:

   '; 
10.   foreach($items as $item) { 
11.     $html .= $formatter($item); 
12.   } 
13.   
14.   return $html; 
15. }