From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: =?UTF-8?Q?Cl=c3=a9ment_Pit-Claudel?= Newsgroups: gmane.emacs.devel Subject: Re: [PATCH] Add new lisp function length= with bytecode support Date: Mon, 6 Mar 2017 15:45:32 -0500 Message-ID: <99375f4d-f627-8e29-2c1f-9d3bfdf3ddd1@gmail.com> References: <64Kl8OYdaKer-3Ey7GHVD9He6bX8yYHaS_NjEwp7Wqc4Zb7xu8IQV3ExvjCLKlBWHVVr_HNUhd55i_BVXNHnpxjnXc6hPgWvWkc3bIO8e7s=@protonmail.com> <87shmy652f.fsf@linux-m68k.org> <-oad61IjWjfeUSwQ5oDR_0rzoc5JtVNOUzoEFCLeetTb9B29QSfWMUdprGdmeDMuyJt38l5W6NC97iCV0VLbBUGGF6K_6-lBf-t_N1_V6aA=@protonmail.com> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Trace: blaine.gmane.org 1488833149 923 195.159.176.226 (6 Mar 2017 20:45:49 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Mon, 6 Mar 2017 20:45:49 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.7.0 To: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Mon Mar 06 21:45:40 2017 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 1ckzVj-0007vc-DH for ged-emacs-devel@m.gmane.org; Mon, 06 Mar 2017 21:45:39 +0100 Original-Received: from localhost ([::1]:46040 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ckzVp-0004ba-Cn for ged-emacs-devel@m.gmane.org; Mon, 06 Mar 2017 15:45:45 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:48737) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ckzVi-0004bK-KQ for emacs-devel@gnu.org; Mon, 06 Mar 2017 15:45:39 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ckzVg-0001Je-35 for emacs-devel@gnu.org; Mon, 06 Mar 2017 15:45:38 -0500 Original-Received: from mail-qk0-x22b.google.com ([2607:f8b0:400d:c09::22b]:33014) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1ckzVf-0001G9-Ug for emacs-devel@gnu.org; Mon, 06 Mar 2017 15:45:36 -0500 Original-Received: by mail-qk0-x22b.google.com with SMTP id y76so43489185qkb.0 for ; Mon, 06 Mar 2017 12:45:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-transfer-encoding; bh=8RgjYqPQ+XiXH4kD3FNpwjHZinz+ULKXX+4f3Pc0B8M=; b=WQdM+x6GiMR7Wx4y43jDp8dBWHZnlswHgyISZBwXMXjXbaiPMM0wNFjrMc7lqV5vM4 IszYFHtEBhA5e/tct2jwYypGYUuJrH7Rb08XLykJ9PPw5nEwWVIFhKsQ5WSCZKVlli9A /gOdq8ZqT4+PNMDRTWNHroDPrZvz8NssZ10/8SZSQzvUq8LsiRIFtjxcIjvw8aJXBiCX 8EE2jDBmmiP9GLPfeVcJJ9TcYBz1I8QVaaYQwXeGwDs4KcRET+XrWjRq8JhqsobUXB6N FR2IEa/GmmMZEcjxd2vlBKLzaeZQDFb8gdEcUfBFHqu0bkExnOlf4ym7Cz9quhoXTdAP x/lg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding; bh=8RgjYqPQ+XiXH4kD3FNpwjHZinz+ULKXX+4f3Pc0B8M=; b=RAFt87CpKUoOu4e+/ZHG1RTyn0r7YP6reVAEcGK6j/SrCD0sIguW8pftLoapntfRa+ XWSW7DmWJAiSHFMVcXT/NV6+GiIAPPJkcLbbHqqQL5D5gZ53p1R+MKXna9wenhqo6EQe zLAK8nXjKTOxNc7/yrqsLPfV1JMRS7FJV/hAsnXQOvfhbnjQxKPiA80LZ2WocgHHhDWQ lQdeO/c4JYFpHzjKRl60pVNuL9ke3GfvVU8cYBdPG7qU/fUIUEhcB9FBumrEo741KBJf dJI4uq7etrbBD6M2UpXBUE5UvFJ0FZ6p3M9R4MaThBvV5aPXAdp/o22Ei7H+kFdOg1z5 wt8w== X-Gm-Message-State: AMke39mdIyOn7Gq8mZEEyGzdd3U3Maf66/eVjLlzIRCHplrfJR1f9EkNLX1b3W2eo+3xCg== X-Received: by 10.55.175.196 with SMTP id y187mr19524358qke.126.1488833133777; Mon, 06 Mar 2017 12:45:33 -0800 (PST) Original-Received: from [18.189.6.43] (dhcp-18-189-6-43.dyn.MIT.EDU. [18.189.6.43]) by smtp.gmail.com with ESMTPSA id h184sm14109077qkf.68.2017.03.06.12.45.33 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 06 Mar 2017 12:45:33 -0800 (PST) In-Reply-To: X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:400d:c09::22b 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:212801 Archived-At: On 2017-03-06 15:36, Gdobbins wrote: >> Why add length= as a primitive? Why is it important enough to >> justify that? > > … I don't really see a purpose in using nthcdr like you have in a > lisp implementation of length=, it isn't any better than just using > length directly since it requires just as much linked list traversal. Isn't Richard's code much faster for long lists and small Ns thank taking the length of the list? Clément.