Easily, the annotation parser ignores all comments that it doesn't recognise.

    /**
     * @var integer $id
     *
     * @ORM\Column(name="id", type="integer")
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     * some comment that the doctrine parser will ignore completely
     */
    private $id;

by escaping them?

Some annotations are meant to affect the code, some aren't. Those who do and need to be given as pure comments need to be escaped.

So now you have a system for putting comments inside your comments? Are you going to eventually start putting meta-annotations inside your meta-comments, and inventing meta-meta-comments so you can comment on the meta-annotations?

Actually, no. What I have now is comment blocks which may contain normal annotations and escaped ones. There's no need to go deeper in meta-meta-something.

Regarding the comment inside comment system, if it were possible to have nested comments, it wouldn't be a problem anymore :). Since it's a Symfony convention, one could simply count the number of stars at the beginning of a comment line to know the meta-comment depth level. BTW, I know that you are being sarcastic here.

Anyway, this is beside the original problem. Annotations in comments are a problem, granted, but somewhat limited. It's easier and faster for a parser to look for comments and then annotations in them, rather than parse the whole PHP grammar augmented with annotations. Especially in PHP.

So now you have a system for putting quotation marks inside your strings? Are you going to eventually start putting escaped-quotation marks inside your escaped-quotes, and inventing escaped-escaped-quotation marks so you can quote the quoted-quotation marks?

In other words, there is no need for some kind of elaborate escapes-upon-escapes method here, all you have to do is not start a comment line with *@.

By not using / * * to start your comment block ?

If you're going to have different syntax for annotations and actual comments, why not choose a syntax that's properly different and not just a weird mutation?

Because they want something that is still valid PHP.

But why? Do I misunderstand that these annotations change the meaning of the code? Why would you want something that's still valid PHP without them, but means something else?