在PHP 7匿名类中访问外部变量

Question

PHP 7 added support for anonymous classes, however I can't seem to find any information regarding associated scoping issues. I know I can use the use keyword with callables/closures to access outer scoped variables (like function() use ($outer) { // do work with $outer }), is there any way to do that with an anonymous class?

I would like to be able to do so without relying on the anonymous class constructor arguments, and without doing things like adding a setter method or public property to store the value after the instantiation.

Here's an example:

$outer = 'something';

$instance = new class {
    public function testing() {
        var_dump($outer); // would like this to dump the string 'something'
    }
};

Answer 1

another solution could be

$outer = 'something';

$instance = new class($outer) {

    private $outer;

    public function __construct($outer) {
        $this->outer = $outer
    }

    public function testing() {
        var_dump($this->outer); 
    }
};