From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Po Lu Newsgroups: gmane.emacs.devel Subject: Re: Conditional binding and testing of `lexical-binding' Date: Sun, 02 Jan 2022 20:41:55 +0800 Message-ID: <874k6mjomk.fsf@yahoo.com> References: Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="6985"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.60 (gnu/linux) Cc: Drew Adams , "emacs-devel@gnu.org" To: LdBeth Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Sun Jan 02 13:44:39 2022 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 1n40E3-0001eZ-E1 for ged-emacs-devel@m.gmane-mx.org; Sun, 02 Jan 2022 13:44:39 +0100 Original-Received: from localhost ([::1]:40804 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1n40E1-0003Bz-HD for ged-emacs-devel@m.gmane-mx.org; Sun, 02 Jan 2022 07:44:37 -0500 Original-Received: from eggs.gnu.org ([209.51.188.92]:51756) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1n40Bd-0002RK-EH for emacs-devel@gnu.org; Sun, 02 Jan 2022 07:42:09 -0500 Original-Received: from sonic317-34.consmr.mail.ne1.yahoo.com ([66.163.184.45]:38477) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1n40Bb-0002Cl-Il for emacs-devel@gnu.org; Sun, 02 Jan 2022 07:42:08 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s2048; t=1641127325; bh=MJvFfaO6fdBAs/vzL8EJuMuoMw1Hl/D97uHAWyYK3jE=; h=From:To:Cc:Subject:References:Date:In-Reply-To:From:Subject:Reply-To; b=dcj6ckxaimZxswL+TNgb9G0UUTbXPLyeEIkFHRXplVNNZLLu+KfbSF7nfVgi/s4KcxsUtmggCyudN8V82b2kvBmNUZb++r+FUQFXBtfNKA8QPePQgfG5BrnOhC2XyvGQQ3V3qtVWju/TP+P7HiQRA5mChLZRFhEIKzWMp0JhHlNVyDdB43XK6c2v8b+UgLsr5RGzq5ZL00kbgklZV6fDBmB0xdlPu3rqEhjojhqdcAgD9dR2YKVKYvR0nlLc9SzRuOuH/nErFJGaon1N2pXKlZhlvqJ8GxZqlfaTWQ1KNCFnJ6l1xToB4rDe8cPVFw39K+oPluw23uC/JiAUaaZYcw== X-SONIC-DKIM-SIGN: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s2048; t=1641127325; bh=EBCJMD8egR2so7iSqcx0ZmCBtOXcUtEFCtaAZQ+Wo3i=; h=X-Sonic-MF:From:To:Subject:Date:From:Subject; b=H/5PDPm7K3RpCiKd4598qWQNZu3cC5vEHcldZYU0B6g/WIDgEnf5Iq8H+B4kVBI43oqqe3L8MmzdVV8aBf7XTYrfv1LZ1wIay14F9L/M1uiDQ3l094chJE5VX9DUO3GhpqHkymUMS3u0ZUxFAj4CpnzFUr1DziU8hvohnRAcyfzcgWZA5aDSLK+H1qqUhNEa61I6EQN4cRW8MjLg9LIFhuvvfJQ8CwQxqRoQVrVGlHz1ZzIVf36ApcNp6TuFSTKXhtZQRKuNvPK6XUYe933Etk9n2o9JXPRFk12OyWbWacY/pMAPISJts/a5uCEFighauL3t97OB5NEU/UJcYD1uxg== X-YMail-OSG: HuMvbrgVM1ksNvOorq39IG1aydP6VpMNNCCtCWuE6SWPHSZmZpHRmp4FtAuh1GM zVHjc4WiiMkP6oJh.PU_JUOY8gQzm49pG9IDvRaypcfyentVT9Bjq30VvzTtK4qFzlOFKdg3EShN pibTkjSZ1IAK6ZlUCCCUQnD7LU8fsxKrtlsUXaDGbGK4DDOUTYUYayzDojTuunVNzWqoBP.QNZBF qq3CMbxCO7It.74L5WTJ9Nm0GQLTgdBIWToooetvkzQZ1dL43vNZ_XQ5U6Qs8sKjKJ5J5Mwl_XZn k6fOM9qfu9iU6VPHIGwb45Bbwyoye5MKv5buGOVfWEBhPYk08rckUmve1G7h9cyEY268coARFJqU gIBEsYaIT05uB5D10EmwLYWzje8iGaUJEU5WmjrYhn.mW8ww_OOdbHqKg_Dkc2_EVF0M6KEtt3_F En0DrXR47fDQw9ucAhT1Q_4kqFWF5qRdxCvIAiRCc.SXnuiRifXQ8eKlm0N91tK0HmlOupFrjhjz UxvR5HU.kmybeMYF1t3EiY_0AbSIti_LaG2CMPjEpuF7BwOd45QH4uy0vlEPWwTmlNDXZ1nzYiP2 eh8UogDp9hJcvrw.uEPrC_UQLNFziEq0Fp_P7bLArJASiBX8Y0skNutKMykmBNJAa4m_QtUE0NEU mlYfbkvrSO.1FE4dHcwjw0ikhCxLj.FpK4EYsxB43ri5T3WbT1FsfZXC4Gf5NnIQJjv7xEay38aq fNX7QOARgykOp7EA4Vq2lvu.slui2id5M4AwciG7T7YsMHalUTjtsgKVh_vi4eOD.sgLGyIrn4X_ QKjsAaBTbs8ao01hdebKscRWLP4AWlCygoFby9H7ls X-Sonic-MF: Original-Received: from sonic.gate.mail.ne1.yahoo.com by sonic317.consmr.mail.ne1.yahoo.com with HTTP; Sun, 2 Jan 2022 12:42:05 +0000 Original-Received: by kubenode512.mail-prod1.omega.sg3.yahoo.com (VZM Hermes SMTP Server) with ESMTPA ID acb582bbd7121b0356036473a26f4cd1; Sun, 02 Jan 2022 12:42:00 +0000 (UTC) In-Reply-To: (LdBeth's message of "Sun, 02 Jan 2022 20:36:26 +0800") X-Mailer: WebService/1.1.19551 mail.backend.jedi.jws.acl:role.jedi.acl.token.atz.jws.hermes.yahoo Received-SPF: pass client-ip=66.163.184.45; envelope-from=luangruo@yahoo.com; helo=sonic317-34.consmr.mail.ne1.yahoo.com X-Spam_score_int: -1 X-Spam_score: -0.2 X-Spam_bar: / X-Spam_report: (-0.2 / 5.0 requ) DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 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:283903 Archived-At: LdBeth writes: > (static-if (assoc 'lexical-binding (buffer-local-variables)) > (provide 'lexical-binding)) > > instead of doing `boundp' test. I think it should be runtime, because transferring compiled code between Emacs 23 and more recent versions is relatively common IME. >> Is this the thing to do? If not, what advice >> do you have for adapting a library to use >> lexical binding when available (Emacs 24+) but >> to also work when it's unavailable (Emacs < 24)? >> [The doc just tells you how to convert code to >> use lexical binding. I see nothing about how >> to code compatibly for old and new Emacs.] +1, there should at least be a paragraph or two in the Lisp reference manual about that. OTOH, I don't think there's much to be gained by using lexical binding at all in code that's supposed to be compatible with versions of Emacs without lexical binding. It's not that important.