Comments in regular expressions (PHP)?

Question

PHP

For regular expressions, it is possible to define comments: "/(?#comment)/".
And how to write this comment correctly when the regular expression is written like this:
"#(?#comment)#"?
The # symbol is convenient to use when parsing URLs often and a lot, so as
not to escape each /.
Thanks in advance for answering this possibly stupid question. It’s just that either Google doesn’t know, or I couldn’t explain to him normally what I need.

Answer 1

Use a different delimiter character. Few of them, right?
@~!%

Answer 2

1) "#(\?\#comment)#"
2) "'(\?#comment)'" (there is a single quote inside, instead of # => " ' ' ")