From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Philipp Stephani Newsgroups: gmane.emacs.devel Subject: Re: Arbitrary function: find the number(s) of expected arguments Date: Sat, 19 Mar 2016 17:16:55 +0000 Message-ID: References: <56E8906C.5050405@lanl.gov> <83egb68vfy.fsf@gnu.org> <87zituefp9.fsf@web.de> <83a8lu8srs.fsf@gnu.org> <87twk2ebp2.fsf@web.de> <838u1e8od1.fsf@gnu.org> <8360wi8mbo.fsf@gnu.org> <834mc28m3j.fsf@gnu.org> <8337rm8lfc.fsf@gnu.org> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: multipart/alternative; boundary=089e0122925e58f054052e6a0873 X-Trace: ger.gmane.org 1458407833 1193 80.91.229.3 (19 Mar 2016 17:17:13 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 19 Mar 2016 17:17:13 +0000 (UTC) Cc: michael_heerdegen@web.de, emacs-devel@gnu.org To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sat Mar 19 18:17:13 2016 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1ahKUy-0001Mt-R6 for ged-emacs-devel@m.gmane.org; Sat, 19 Mar 2016 18:17:13 +0100 Original-Received: from localhost ([::1]:49775 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ahKUy-0001zC-8C for ged-emacs-devel@m.gmane.org; Sat, 19 Mar 2016 13:17:12 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:40332) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ahKUt-0001vO-1Y for emacs-devel@gnu.org; Sat, 19 Mar 2016 13:17:07 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ahKUs-0005Qd-3x for emacs-devel@gnu.org; Sat, 19 Mar 2016 13:17:06 -0400 Original-Received: from mail-lb0-x22e.google.com ([2a00:1450:4010:c04::22e]:35831) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ahKUr-0005QZ-Ni; Sat, 19 Mar 2016 13:17:06 -0400 Original-Received: by mail-lb0-x22e.google.com with SMTP id bc4so105653637lbc.2; Sat, 19 Mar 2016 10:17:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=U6fRda1LCqQ53RppiNiJn5UmyhK/ewy8gaQj49p99Fw=; b=hCw4fg2SMkY3YejJyehcqjqxCkt7idNLYcLptzv5Ayvxyz+BmBBV02zBuXSdkxVYHu HxlmMNyb+33ZCIa+mSOS32X5LnVbHfWft1xZEobjTm25sj4WSwune5xvtG0bOY7NUd27 EqL8yO8K1S1s5LrfGcM+swa4p+im+IM0O6SEgsY7MIZ7hhmuUTvbvXTf14ySCo0cmSIV EePoJnpkTKgCyw2a93o+4vwzQ0SzdshwI6UXO24xw9ac199sIkZxbij0/wYJgU2OYyz6 3MYeC4pvFTPZhVtCNQUktdbFTeN+HqXDiYFxRag2jj8nzj1U+8tV1lSvxaSLoSekFbKX H8Xw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=U6fRda1LCqQ53RppiNiJn5UmyhK/ewy8gaQj49p99Fw=; b=KvoUKV7uXVzSUV4137UHuC775y7BNrMEaqOybWrTp8yKcJDK1unDuVorB0FqjU3E/b Y+xooqiSXuE/hjRRpDJCiA5/UQ5xt84N2lnpNiqB5+nbFcwTG1abbOAu9KttH88vO8iZ B+IbSrAKXiPb0dOVenxUr8aYIvZ0ZFNyLF2aE1VBMKJr3zWH6pNikoSG40pfNC4406qb zX5cOUZmwSn3aiHrSaGawsImEWDlRLkmb6PlWH2s3mmCKO05txFWZkmkL9V9Uy9eOUNU MM4RW/zyF3RYR5HtBJlshuokAYskBvEv7L/UjI8NWgQcOOKxTSQsZIov+kugrabaLhjl fjPw== X-Gm-Message-State: AD7BkJIBXDCiP53iMnNNIpZJEo42oYjgGBdE34duG3+xCjVWCcy2oQm60bIYmRqh0GufCBp2VKxN83WsaeA8PA== X-Received: by 10.112.134.138 with SMTP id pk10mr7870489lbb.16.1458407825008; Sat, 19 Mar 2016 10:17:05 -0700 (PDT) In-Reply-To: <8337rm8lfc.fsf@gnu.org> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2a00:1450:4010:c04::22e X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 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.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:201883 Archived-At: --089e0122925e58f054052e6a0873 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Eli Zaretskii schrieb am Sa., 19. M=C3=A4rz 2016 um 17:47 Uh= r: > > From: Philipp Stephani > > Date: Sat, 19 Mar 2016 16:34:55 +0000 > > Cc: michael_heerdegen@web.de, emacs-devel@gnu.org > > > > > (g 10 202 30) =3D> error -> "Wrong number of arguments" > > > > > > This cannot be detected without evaluating the function. > > > > Are we discussing the usefulness of the function, or are we discussing > > how best to implement it? > > > > > > We are discussing for which cases it can be implemented. It can be > implemented and would be useful for a > > wide range of functions, such as those defined with defun. It cannot be > implemented for functions like g; that's > > just a limitation we have to live with. > > That's one possibility. Another is that the implementation will be > able to find out the truth, just like the Lisp interpreter does. > Presumably that would imply solving the halting problem. --089e0122925e58f054052e6a0873 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable


Eli Za= retskii <eliz@gnu.org> schrieb am= Sa., 19. M=C3=A4rz 2016 um 17:47=C2=A0Uhr:
> From: Philipp Stephani <p.stephani2@gmail.com>
> Date: Sat, 19 Mar 2016 16:34:55 +0000
> Cc: mich= ael_heerdegen@web.de, emacs-devel@gnu.org
>
>=C2=A0 > (g 10 202 30) =3D> error -> "Wrong number of arg= uments"
>=C2=A0 >
>=C2=A0 > This cannot be detected without evaluating the function. >
>=C2=A0 Are we discussing the usefulness of the function, or are we disc= ussing
>=C2=A0 how best to implement it?
>
>
> We are discussing for which cases it can be implemented. It can be imp= lemented and would be useful for a
> wide range of functions, such as those defined with defun. It cannot b= e implemented for functions like g; that's
> just a limitation we have to live with.

That's one possibility.=C2=A0 Another is that the implementation will b= e
able to find out the truth, just like the Lisp interpreter does.

Presumably that would imply solving the halting p= roblem.=C2=A0
--089e0122925e58f054052e6a0873--