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: Thu, 26 Aug 2021 10:25:27 -0700 Message-ID: <87mtp49kzc.fsf@ericabrahamsen.net> References: <875yvtbbn3.fsf@ericabrahamsen.net> <87bl5k87hq.fsf@alphapapa.net> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="11043"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) Cc: emacs-devel@gnu.org To: Adam Porter Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Thu Aug 26 19:26:44 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 1mJJ9I-0002dC-F0 for ged-emacs-devel@m.gmane-mx.org; Thu, 26 Aug 2021 19:26:44 +0200 Original-Received: from localhost ([::1]:56752 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mJJ9G-0004XF-S0 for ged-emacs-devel@m.gmane-mx.org; Thu, 26 Aug 2021 13:26:42 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:49304) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mJJ88-0001GE-VQ for emacs-devel@gnu.org; Thu, 26 Aug 2021 13:25:32 -0400 Original-Received: from mail.ericabrahamsen.net ([52.70.2.18]:51900) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mJJ87-0006Cg-6T for emacs-devel@gnu.org; Thu, 26 Aug 2021 13:25:32 -0400 Original-Received: from localhost (75-172-126-110.tukw.qwest.net [75.172.126.110]) (Authenticated sender: eric@ericabrahamsen.net) by mail.ericabrahamsen.net (Postfix) with ESMTPSA id 4B2DAFA07F; Thu, 26 Aug 2021 17:25:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ericabrahamsen.net; s=mail; t=1629998729; bh=tZXRiD2gpVy+upUd9ll77LmPeOwzY+7amMG9dS7Sybc=; h=From:To:Cc:Subject:References:Date:In-Reply-To:From; b=fjp3TpYH1zvl+wmrQdtaitZp4yWT+ved98Xw0aJeoFMEbfoL404U1HdL2bWjwGRnb yC0AXV3qHEAss17m5OTMXeuYeWBEclJbF7glTLH78DeNBawLP9lhv4r5owjYKgBeEv pz3/up0dP4+RL5huv1GMGnzTvzBTm6psyLY0EO4s= In-Reply-To: <87bl5k87hq.fsf@alphapapa.net> (Adam Porter's message of "Thu, 26 Aug 2021 12:02:09 -0500") Received-SPF: pass client-ip=52.70.2.18; envelope-from=eric@ericabrahamsen.net; helo=mail.ericabrahamsen.net X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham 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:273053 Archived-At: Adam Porter writes: > FWIW, I've been happy using peg.el in org-ql. I use it to parse strings > like: > > "todo:WAITING scheduled:from=2021-08-01,to=2021-08-31" > > into a sexp like: > > (and (todo "WAITING") > (scheduled :from "2021-08-01" :to "2021-08-31")) > > You can see the code I use here: > > https://github.com/alphapapa/org-ql/blob/master/org-ql.el#L854 This is very helpful, thanks. The peg.el comments are not very helpful when it comes to actions, so it's great to have more examples. I'll try to provide a comment patch to the library once I've made more progress. > I can't speak much to its performance, because it's plenty fast enough for the > relatively light usage it gets in org-ql. In gnus-search.el it would be the same situation: performance wouldn't matter at all. If I can use it for IMAP server parsing, though, it would be important not to be too slow. > My only, minor complaint is that I ended up having to use `eval' on > its `with-peg-rules' macro at runtime: > > https://github.com/alphapapa/org-ql/blob/94f9e6f3031b32cf5e2149beca7074807235dcb0/org-ql.el#L908 > > I tried many, many things before resorting to that, so I don't think I > missed any alternatives at the time. If that aspect of the API could be > improved, it would be welcomed, but I don't think it's necessary to do > so before adding it to Emacs. > > (The issue is that the tokens that are parsed can be added to at > runtime, so they are stored in a variable, and the parsing function is > redefined as necessary at runtime, so it's not possible to define the > parser fully at expansion time.) This doesn't mean much to me (yet), but I'll keep an eye out! > Thanks for suggesting this, Eric. Thanks for pointing out that it exists!