From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Emanuel Berg via Users list for the GNU Emacs text editor Newsgroups: gmane.emacs.help Subject: Re: [DOC] About Lisp Data Types Date: Sun, 01 Aug 2021 16:04:09 +0200 Message-ID: <8735rtjm7a.fsf@zoho.eu> References: <87h7g9h67j.fsf@laposte.net> <877dh5l7rv.fsf@zoho.eu> <87y29ljs26.fsf@zoho.eu> <875ywpgw0v.fsf@laposte.net> Reply-To: Emanuel Berg Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="7632"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) To: help-gnu-emacs@gnu.org Cancel-Lock: sha1:ijCQpWNa5NjG4SCYw68NaK8wN3U= Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Sun Aug 01 16:05:14 2021 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 1mAC5Z-0001iE-HF for geh-help-gnu-emacs@m.gmane-mx.org; Sun, 01 Aug 2021 16:05:13 +0200 Original-Received: from localhost ([::1]:60254 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mAC5Y-0000hG-6r for geh-help-gnu-emacs@m.gmane-mx.org; Sun, 01 Aug 2021 10:05:12 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:33882) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mAC4m-0000h7-09 for help-gnu-emacs@gnu.org; Sun, 01 Aug 2021 10:04:24 -0400 Original-Received: from ciao.gmane.io ([116.202.254.214]:52018) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mAC4i-0006zo-Sl for help-gnu-emacs@gnu.org; Sun, 01 Aug 2021 10:04:23 -0400 Original-Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1mAC4h-0000WF-0X for help-gnu-emacs@gnu.org; Sun, 01 Aug 2021 16:04:19 +0200 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: -26 X-Spam_score: -2.7 X-Spam_bar: -- X-Spam_report: (-2.7 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.249, NICE_REPLY_C=-1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.23 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" Xref: news.gmane.io gmane.emacs.help:132272 Archived-At: Kevin Vigouroux via Users list for the GNU Emacs text editor wrote: > I agree with you. Unfortunately, some parts of the > explanation are unclear or missing. > > In other languages, an expression is text; it has no > other form. Actually I agree this isn't clear, in C there are for example expressions that can be simplified to a single value by the human and also evaluated to that value by the compiler. So on the contrary arguably it has several "forms" within its textualness but also in terms of before/after evaluation. Also "In other languages" is very inexact, what languages are those if I may? Because there are so many languages that does anything and everything in so many different ways. > In Lisp, an expression is primarily a Lisp object and > only secondarily the text that is the object’s read > syntax. Why primarily one thing and "only secondarily" something else? If it is both, isn't it one thing as much as the other? Also, isn't it just source and syntax - in Lisp, parenthesized lists AKA s-expressions - that evaluates to Lisp objects - that in turn can be expressed as, and evaluates to, source and syntax, i.e. parenthesized lists AKA s-expressions? Isn't the object just the run time instance of static source, an s-expression, that has been evaluated during the execution of the program? > Often there is no need to emphasize this distinction, but > you must keep it in the back of your mind, or you will > occasionally be very confused. Better to provide clear definitions: 1. s-expression = ... 2. Lisp object = ... 3. read syntax = ... -- underground experts united https://dataswamp.org/~incal