How can I create an object inside a class?

How can I do this, as the most obvious way doesn't work:

<?php

    class Inner {

    public $var;
    }

    class Outer {

    $test = new Inner;
    }

?>

Yields:

Parse er开发者_如何转开发ror: syntax error, unexpected T_VARIABLE, expecting T_FUNCTION in /f5/debate/public/test.php on line 10

In PHP you can't instantiate a class as a default value of a property. You need to do it in a function (in this case, probably likely the constructor). eg.

class Inner {
    public $var;
}

class Outer {
    public $test;

    public function __construct() {
        $this->test = new Inner();
    }
}