From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Eric Abrahamsen Newsgroups: gmane.emacs.devel Subject: Re: Make peg.el a built-in library? Date: Sun, 10 Oct 2021 14:40:37 -0700 Message-ID: <87v924lfsa.fsf@ericabrahamsen.net> References: <875yvtbbn3.fsf@ericabrahamsen.net> <87a6jjc7c8.fsf@web.de> <874k9qxhzj.fsf@ericabrahamsen.net> <87ee8tv7cj.fsf@web.de> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="31410"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/29.0.50 (gnu/linux) To: emacs-devel@gnu.org Cancel-Lock: sha1:BYcL9oEK2hFCgLf/wjLDOTTNycQ= Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Sun Oct 10 23:41:47 2021 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1mZgZn-0007zE-HT for ged-emacs-devel@m.gmane-mx.org; Sun, 10 Oct 2021 23:41:47 +0200 Original-Received: from localhost ([::1]:52614 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mZgZm-0002Tm-E7 for ged-emacs-devel@m.gmane-mx.org; Sun, 10 Oct 2021 17:41:46 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:54298) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mZgYv-0001eQ-B8 for emacs-devel@gnu.org; Sun, 10 Oct 2021 17:40:53 -0400 Original-Received: from ciao.gmane.io ([116.202.254.214]:36790) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mZgYt-0003EY-Di for emacs-devel@gnu.org; Sun, 10 Oct 2021 17:40:53 -0400 Original-Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1mZgYq-0006mN-1I for emacs-devel@gnu.org; Sun, 10 Oct 2021 23:40:48 +0200 X-Injected-Via-Gmane: http://gmane.org/ Received-SPF: pass client-ip=116.202.254.214; envelope-from=ged-emacs-devel@m.gmane-mx.org; helo=ciao.gmane.io X-Spam_score_int: -16 X-Spam_score: -1.7 X-Spam_bar: - X-Spam_report: (-1.7 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.249, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.io gmane.emacs.devel:276705 Archived-At: Michael Heerdegen writes: > Eric Abrahamsen writes: > >> >> (1) Can we improve the introduction in the file header a bit? I would >> >> add a link to the wikipedia page: >> >> >> >> https://en.wikipedia.org/wiki/Parsing_expression_grammar >> >> >> >> it explains some background. >> > >> > I can't speak for Helmut, but I think you should feel free to make such >> > a change, yes. >> >> I've still got this documentation patch I haven't applied, I can just >> add that link to this patch? > > From my side, nothing against that. I have quickly skimmed over your > text and found nothing obviously wrong or confusing, and it makes some > things a bit clearer. > > Should we say something about how to use globally defined pegs? AFAIU > you can use them like (my-peg) in parens, contrary to rules, which > appear as plain symbols. At least, this was one of the things I > wondered while trying this out: what do I have to wrap in > parens. I'm not quite sure what you mean here. If you use the `define-peg-rule' you can use the symbol plain, you don't have to wrap it in parentheses. If you want to use one of the built-in action functions, like "substring", then you have to wrap your symbol in that, same as if you were defining a rule on the spot. But that's just for convenience. The shorthand: (substring ) is defined as: (and `(-- (point)) `(start -- (buffer-substring-no-properties start (point)))) I don't think you have to wrap anything in parentheses, though you *can* if you want to, and it will work correctly. Am I misunderstanding you? Eric