From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: =?utf-8?Q?=C3=93scar_Fuentes?= Newsgroups: gmane.emacs.help Subject: Re: (*) -> 1 Date: Tue, 17 Jan 2023 23:01:58 +0100 Message-ID: <87zgagakh5.fsf@telefonica.net> References: <87sfg9kuya.fsf@web.de> <87bkmxkpzg.fsf@web.de> <878ri1av5j.fsf@telefonica.net> <87ilh4kgqo.fsf@web.de> 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="36604"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) To: help-gnu-emacs@gnu.org Cancel-Lock: sha1:ZTFCgjpVPUZVmFUF9vWyKHyy/PA= Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Tue Jan 17 23:02:40 2023 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 1pHu2S-0009HC-1G for geh-help-gnu-emacs@m.gmane-mx.org; Tue, 17 Jan 2023 23:02:40 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pHu20-0002mm-VZ; Tue, 17 Jan 2023 17:02:12 -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 1pHu1y-0002mb-QR for help-gnu-emacs@gnu.org; Tue, 17 Jan 2023 17:02:10 -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 1pHu1x-0006Na-58 for help-gnu-emacs@gnu.org; Tue, 17 Jan 2023 17:02:10 -0500 Original-Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1pHu1u-0008Rh-JZ for help-gnu-emacs@gnu.org; Tue, 17 Jan 2023 23:02:06 +0100 X-Injected-Via-Gmane: http://gmane.org/ 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-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:142341 Archived-At: Michael Heerdegen writes: > Óscar Fuentes writes: > >> In other programming languages an expression such as "+ 2" would yield a >> partially applied function: >> >> let f = + 2 >> f 5 >> -> 7 > > The "dual" problem can also exist in this interpretation of notation, > though: > > Would a partial application of `*' to no arguments result in a function > multiplying the product of the arguments (with 1), or would it result in > a function raising an error? What would this function applied to no > arguments return? The function either has all arguments satisfied (and then it is computed) or not (and then it is a partially applied function). So `f' in the previous example: f -> f * 3 -> * 3 > What would the partial application of `-' to a number return when > applied to no arguments? Etc. I'm not sure I understand this question. Maybe this: let f = - 5 f 3 -> 2 or let f = - _ 3 ;; `_' stands for "absent argument" f 5 -> 2 The languages that use the concept of partially applied function usually have no support for variadic functions, so the duality problem you refer to is not an issue.