From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Michael Heerdegen Newsgroups: gmane.emacs.devel Subject: Re: Make peg.el a built-in library? Date: Sun, 10 Oct 2021 06:46:05 +0200 Message-ID: <87zgrhh4he.fsf@web.de> References: <875yvtbbn3.fsf@ericabrahamsen.net> <87a6jjc7c8.fsf@web.de> <87v926w3bs.fsf@ericabrahamsen.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="18984"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/29.0.50 (gnu/linux) Cc: Eric Abrahamsen , emacs-devel@gnu.org To: Stefan Monnier Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Sun Oct 10 06:47:53 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 1mZQka-0004ie-Vm for ged-emacs-devel@m.gmane-mx.org; Sun, 10 Oct 2021 06:47:52 +0200 Original-Received: from localhost ([::1]:45250 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mZQkZ-00032b-Ec for ged-emacs-devel@m.gmane-mx.org; Sun, 10 Oct 2021 00:47:51 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:50062) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mZQjE-0002Je-4Z for emacs-devel@gnu.org; Sun, 10 Oct 2021 00:46:28 -0400 Original-Received: from mout.web.de ([212.227.17.12]:42289) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mZQjC-0005ZV-DI for emacs-devel@gnu.org; Sun, 10 Oct 2021 00:46:27 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=web.de; s=dbaedf251592; t=1633841167; bh=G/HIPIOBKCke6uPTBjLXK68Ivis/vBKew/XTOEUK3fo=; h=X-UI-Sender-Class:From:To:Cc:Subject:References:Date:In-Reply-To; b=MhVOp/Hn3PTvS2q823J9MibiQJSrlltiLWeiDMj6Grd+dsMpW1Yh91mLJZITrrum7 B55kmjg0bXUAV+BGblgVnNUikCYQdEMbQMkhcGVZsEuOLmvH+NKOCXoFnypOzdva0Y iU6hSHeBpAjXRwjc1CypYEX93XQQerao7TO5iN2A= X-UI-Sender-Class: c548c8c5-30a9-4db5-a2e7-cb6cb037b8f9 Original-Received: from drachen.dragon ([92.208.225.87]) by smtp.web.de (mrweb101 [213.165.67.124]) with ESMTPSA (Nemesis) id 0MTh2S-1m8vex12Ya-00QSdI; Sun, 10 Oct 2021 06:46:07 +0200 In-Reply-To: (Stefan Monnier's message of "Sat, 09 Oct 2021 23:43:28 -0400") X-Provags-ID: V03:K1:rnbHGbsOdWvO3Ov15KhOQMGErIakwkM4gfYwYinrTi2XLR1JcZy 5imIGXLCNDBmpHf5v7mg6mtS0Fa0NBTfGbzxbMn4dgi08pxb1+SB1jz5yJfMd3495CZbWuX ewCO/KqeO+wJ5QmCE6uEEkZv4cG2zQYSmGwYNr7Bsan5PopHJZlMH2WrpUZb+5lfxXIFpT5 cVQqCY8/c5Ukd++xPelZQ== X-UI-Out-Filterresults: notjunk:1;V03:K0:qY6SVUEdEUs=:W4KLuxqRHuDbTLy5lDEsNi nO2EOdYxqjDogDHIMJqWqBS1ULbXlflZxaheQkvI+Sh6a4f3QmcA7E/bk6bbF6RZ8qqeZKFZj YnDdulukjqDfX4yBJmBhXO3sujA37M7dECvDwMfcxQFPbNW6d1fIo0grGmn9W0WVt9CXfM0rq 9eNluWs+uX34pq+dOgQM3M70poi3Z86p67Fj9VH1+u4jPcrY6sVOG1wshQjeTWGLWkU5clFbV 5DM+hWGzC9mtf0tvcdto7sbfMpt+y2ojuXQBo3CnKUrbZ2FUMDB+omULA9SSIpztP5xeD3v1j /S4fukgCv7t0bAYADBHKAPyT9KdPXBmCQA57GNFU2vO59+cb1f1K18VCPdlQFWsH06WTLDaiu XfvepVsavj6uoBlPb9nIemf7YxT/Z/MQcirV4EVyHtFDXXWrL++fINAEyfGooXvI18N1s1SiB d7YUllDSGK74bFfSYk93nxsxi6UOwsHAb94g+ETlM4IOHm6hN3p5p9vSe5LSNPaoNeXWQUZbH vdsvIufdzzFdQh9rroY5e0hHKF3EyOrX29ts2ey6lo+LufyG3lD67kKq40ZLirEKRDWZe5uMK TGc75WGrH3Gei8huwi7bBiAv39hEbiS6eZDVu0NIX9YVn00PoncnYhG3TwlHncv0ZN8DpZsRq NYKB6RK5IamNn5RKGUgbcbg85JQZz7ovm35K6toO8tuzhuLdSDQ/SQMmOQ3jNW0tyjCSsDOTH 8iSCFeYwX9UDA20GMWDFX702J3H1aSchaT3YtxQ9yQORQ/kqEAWzpbrJvZOodb1daNT40TB2 Received-SPF: pass client-ip=212.227.17.12; envelope-from=michael_heerdegen@web.de; helo=mout.web.de X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 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, FREEMAIL_FROM=0.001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, 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:276636 Archived-At: Stefan Monnier writes: > Correctly matching regexps requires a deeper form of backtracking than > provided by PEGs. I learned PEGs are able to accept any type 3 language. I also learned that PEGs alternatives work differently. Is it practically possible to transform a regexp into a really equivalent PEG, or is it too difficult, or would the resulting PEG just be too large or inefficient? Michael.