If annotations are in comments, how are you going to leave actual comments containing annotations that you don't want to actually affect the code?
/**
* @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;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.
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 *@.
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.