bug#36496: [PATCH] Describe the rx notation in the lisp manual

[Eli Zaretskii]

> From: Richard Stallman <rms@gnu.org>
> Cc: mattiase@acm.org, 36496@debbugs.gnu.org
> Date: Fri, 05 Jul 2019 20:10:26 -0400
> 
> In the past, various practical factors have made rx somewhat inconvenient,
> and that prevented rx from competing with the regexp syntax.
> Recently we have made some improvements in rx; are they enough to
> make rx a real competitor for regexps?

I cannot answer the question without knowing which practical factors
made rx inconvenient in the past.  Where can one find this
information?