请教php从哪个版本开始支持new $variable()实例化类
请问php从哪个版本开始支持new $variable()实例化类？
如题，使用变量指定一个类名，通过new实例对象，这是从php的哪个版本里开始支持的？
php手册里没找到，甚至连这种写法都没有看到。
------解决方案--------------------
这很早吧？ php4 就有实例化类了啊。 $a=new b(); 或者 $a =new b;都可以
------解决方案--------------------
类与对象（PHP 4）继承类与对象（PHP 4）
PHP 手册
--------------------------------------------
类
类是变量与作用于这些变量的函数的集合。变量通过var来定义，函数通过 function 来定义，而类则通过下面的语法定义
------解决方案--------------------
php4
引入了类，就有了这种写法
------解决方案--------------------
4就带了
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