From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Emanuel Berg Newsgroups: gmane.emacs.help Subject: options and variables, interesting code Date: Wed, 09 Nov 2022 18:48:39 +0100 Message-ID: <87pmdwvx1k.fsf@dataswamp.org> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="12490"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) To: help-gnu-emacs@gnu.org Cancel-Lock: sha1:xJR7nQKIsyiNetVfvIG2hgUTvI0= Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Thu Nov 10 14:08:39 2022 Return-path: Envelope-to: geh-help-gnu-emacs@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 1ot7IN-00032v-NR for geh-help-gnu-emacs@m.gmane-mx.org; Thu, 10 Nov 2022 14:08:39 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ot7IG-00054w-2Y; Thu, 10 Nov 2022 08:08:32 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ospC1-0007IP-27 for help-gnu-emacs@gnu.org; Wed, 09 Nov 2022 12:48:57 -0500 Original-Received: from ciao.gmane.io ([116.202.254.214]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ospBy-00028K-NG for help-gnu-emacs@gnu.org; Wed, 09 Nov 2022 12:48:52 -0500 Original-Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1ospBw-0007Qz-0p for help-gnu-emacs@gnu.org; Wed, 09 Nov 2022 18:48:48 +0100 X-Injected-Via-Gmane: http://gmane.org/ Mail-Followup-To: help-gnu-emacs@gnu.org Mail-Copies-To: never Received-SPF: pass client-ip=116.202.254.214; envelope-from=geh-help-gnu-emacs@m.gmane-mx.org; helo=ciao.gmane.io X-Spam_score_int: -15 X-Spam_score: -1.6 X-Spam_bar: - X-Spam_report: (-1.6 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.25, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-Mailman-Approved-At: Thu, 10 Nov 2022 08:08:30 -0500 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.help:140886 Archived-At: Here is the idea from the other day ... Note an interesting unintentional thing, this forces options, i.e. global dynamic/special variables, to be defined even before they are used (macro expand time? I have no experience from macros, almost) Or is that a side-effect of byte-compilation? Anyway, it it were like this (maybe not exactly like this) with 'vars' and 'opts' one could have the 'dlet', 'dalet', 'alet', 'salet', and 'slet' (see the other post) for completeness for anyone who would like them for whatever reason, the rest could just use 'vars' for local variables and 'opts' for options, one could enforce lexical/static scope, remove the cookie, and one could forget about the scope - as the dlet people would know it, anyway - and the rest wouldn't care and they wouldn't need to as those (local variable and options) are intuitive concepts by now ... Or am I wrong? Oh, that should be `let*' BTW ... PS. Those macros are so similar, can you replace one with a hypermacro or metamacro? Higher-order macro programming LOL ... ;;; -*- lexical-binding: t -*- ;; ;; this file: ;; https://dataswamp.org/~incal/emacs-init/vars-opts.el (require 'cl-lib) (defmacro vars (binders &rest body) (declare (indent 1) (debug let)) (cl-loop with name-colls = () for (n _) in binders do (when (special-variable-p n) (push (symbol-name n) name-colls) ) finally (when name-colls (error "Name collision%s: %s" (if (< 1 (length name-colls)) "s" "") (mapconcat #'identity (reverse name-colls) ", ") )) ) `(let ,binders ,@body) ) (defmacro opts (binders &rest body) (declare (indent 1) (debug let)) (cl-loop with name-colls = () for (n _) in binders do (unless (special-variable-p n) (push (symbol-name n) name-colls) ) finally (when name-colls (error "No option%s: %s" (if (< 1 (length name-colls)) "s" "") (mapconcat #'identity (reverse name-colls) ", ") )) ) `(let ,binders ,@body) ) (defvar dynavar 2000) (vars ((dynavar 3000) (fill-column 1) (a 0) (y 2) ) y) ; Name collisions: dynavar, fill-column (vars ((fill-column 1) (a 0) (y 2) ) y) ; Name collision: fill-column <-- cute B) (vars ((a 0) (y 2) ) y) ; 2 (opts ((dynavar 3000) (fill-column 1) (a 0) (y 2) ) y) ; No options: a, y (opts ((dynavar 3000) (fill-column 10) ) (delete-char 2) (fill-paragraph) ) ; eval me -- underground experts united https://dataswamp.org/~incal