PHP - class 'My \ Engine \ Control' not found

Question

The following code is included in another file. My\Engine\Controldetermined much earlier and distributed throughout the site without any problems. However, in this one file I get an error:

Fatal error: class 'My \ Engine \ Control' was not found in / mnt / web / ~ / classes.php on line 6

<?php
namespace My\Engine;

// class Control {}

class RequiresAccount extends Control {
    public function permissions() {

    }

}

However, when I try to put the dummy Control class in (uncomment the commented part), I get another error.

Fatal error: class My \ Engine \ Control cannot be declared because the name is already used in / mnt / web / ~ / Control.class.php on line 47

It seems impossible, and I just can't figure it out. I write code like this all the time and only once ...

All other files requiring an extension \My\Engine\Controlwork fine.

Answer 1

, - - , . PSR-4 standard Composer .

, . , , ./vendor/autoload.php composer.json.