From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Paul Eggert Newsgroups: gmane.emacs.devel Subject: Re: Using the GNU GMP Library for Bignums in Emacs Date: Sat, 21 Apr 2018 08:23:33 -0700 Organization: UCLA Computer Science Department Message-ID: <0d3175d8-d996-651e-b221-71978bde3a65@cs.ucla.edu> References: <29f933ac-a6bf-8742-66a7-0a9d6d3e5a88@disroot.org> <83bmecy6fx.fsf@gnu.org> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Trace: blaine.gmane.org 1524324116 11357 195.159.176.226 (21 Apr 2018 15:21:56 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Sat, 21 Apr 2018 15:21:56 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 Cc: emacs-devel@gnu.org To: "Siraphob (Ben) Phipathananunth" , Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sat Apr 21 17:21:52 2018 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1f9uKm-0002sf-43 for ged-emacs-devel@m.gmane.org; Sat, 21 Apr 2018 17:21:52 +0200 Original-Received: from localhost ([::1]:52098 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f9uMr-0008Nx-RG for ged-emacs-devel@m.gmane.org; Sat, 21 Apr 2018 11:24:01 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:55566) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1f9uMl-0008Nj-R8 for emacs-devel@gnu.org; Sat, 21 Apr 2018 11:23:56 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1f9uMk-0003vz-U1 for emacs-devel@gnu.org; Sat, 21 Apr 2018 11:23:55 -0400 Original-Received: from zimbra.cs.ucla.edu ([131.179.128.68]:49756) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1f9uMg-0003ne-DT; Sat, 21 Apr 2018 11:23:50 -0400 Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 03D1A16005C; Sat, 21 Apr 2018 08:23:41 -0700 (PDT) Original-Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id B-zGI-3_42aq; Sat, 21 Apr 2018 08:23:40 -0700 (PDT) Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 02336160860; Sat, 21 Apr 2018 08:23:40 -0700 (PDT) X-Virus-Scanned: amavisd-new at zimbra.cs.ucla.edu Original-Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id PmmqNeArOyVT; Sat, 21 Apr 2018 08:23:38 -0700 (PDT) Original-Received: from [192.168.1.9] (unknown [47.154.30.119]) by zimbra.cs.ucla.edu (Postfix) with ESMTPSA id 466F416005C; Sat, 21 Apr 2018 08:23:38 -0700 (PDT) In-Reply-To: Content-Language: en-US X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [fuzzy] X-Received-From: 131.179.128.68 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 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" Xref: news.gmane.org gmane.emacs.devel:224763 Archived-At: Siraphob (Ben) Phipathananunth wrote: > One approach would be to implement a minimal subset of functions > exposed in Emacs Lisp that would allow one to recreate the following > functions that are defined in calc.el : Surely we should just add bignum support to existing functions +, -, etc.= =20 Wouldn't that suffice for 'calc'? If not, why not? (Of course 'calc' woul= d need=20 to be changed to exploit the bignums properly, no matter how we add bignu= ms.) > With respect to floating points, though, things get a little hairy.=20 This should be a separate task. Bignums alone are quite a large-enough pr= oject.=20 I'm not even sure we should do rationals. > The /actual/ value of the bignum > (internally, in C) would be a tagged pointer to the mpz_t data type > stored somewhere so that it could be marked for GC For bignums I would think that Emacs shouldn't use the mpz_t data type, a= s this=20 would complicate garbage collection. Emacs can use the mp_limb_t data typ= e and=20 stick with the mpn_* functions.