From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Mark H Weaver Newsgroups: gmane.lisp.guile.bugs Subject: bug#17485: [PATCH 3/3] Reimplement reduce-right in srfi-1 Date: Tue, 03 Jun 2014 23:30:25 -0400 Message-ID: <871tv5uzam.fsf@yeeloong.lan> References: <1401821778-19972-1-git-send-email-dak@gnu.org> <1401821778-19972-3-git-send-email-dak@gnu.org> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1401852686 23645 80.91.229.3 (4 Jun 2014 03:31:26 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 4 Jun 2014 03:31:26 +0000 (UTC) Cc: 17485@debbugs.gnu.org To: David Kastrup Original-X-From: bug-guile-bounces+guile-bugs=m.gmane.org@gnu.org Wed Jun 04 05:31:18 2014 Return-path: Envelope-to: guile-bugs@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 1Ws1v3-00042F-Bg for guile-bugs@m.gmane.org; Wed, 04 Jun 2014 05:31:17 +0200 Original-Received: from localhost ([::1]:57021 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Ws1v2-0004zk-VL for guile-bugs@m.gmane.org; Tue, 03 Jun 2014 23:31:16 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:57972) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Ws1uu-0004yY-3g for bug-guile@gnu.org; Tue, 03 Jun 2014 23:31:14 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Ws1uo-0001Uh-7g for bug-guile@gnu.org; Tue, 03 Jun 2014 23:31:08 -0400 Original-Received: from debbugs.gnu.org ([140.186.70.43]:44018) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Ws1uo-0001Ud-4P for bug-guile@gnu.org; Tue, 03 Jun 2014 23:31:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.80) (envelope-from ) id 1Ws1un-0007Ip-QG for bug-guile@gnu.org; Tue, 03 Jun 2014 23:31:01 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Mark H Weaver Original-Sender: "Debbugs-submit" Resent-CC: bug-guile@gnu.org Resent-Date: Wed, 04 Jun 2014 03:31:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 17485 X-GNU-PR-Package: guile X-GNU-PR-Keywords: Original-Received: via spool by 17485-submit@debbugs.gnu.org id=B17485.140185264928047 (code B ref 17485); Wed, 04 Jun 2014 03:31:01 +0000 Original-Received: (at 17485) by debbugs.gnu.org; 4 Jun 2014 03:30:49 +0000 Original-Received: from localhost ([127.0.0.1]:42895 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1Ws1ua-0007ID-Se for submit@debbugs.gnu.org; Tue, 03 Jun 2014 23:30:49 -0400 Original-Received: from world.peace.net ([96.39.62.75]:50657 ident=hope2) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1Ws1uU-0007Hv-1K for 17485@debbugs.gnu.org; Tue, 03 Jun 2014 23:30:46 -0400 Original-Received: from 209-6-91-212.c3-0.smr-ubr1.sbo-smr.ma.cable.rcn.com ([209.6.91.212] helo=yeeloong.lan) by world.peace.net with esmtpsa (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.72) (envelope-from ) id 1Ws1uN-0000x3-Re; Tue, 03 Jun 2014 23:30:35 -0400 In-Reply-To: <1401821778-19972-3-git-send-email-dak@gnu.org> (David Kastrup's message of "Tue, 3 Jun 2014 20:56:18 +0200") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.15 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 140.186.70.43 X-BeenThere: bug-guile@gnu.org List-Id: "Bug reports for GUILE, GNU's Ubiquitous Extension Language" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-guile-bounces+guile-bugs=m.gmane.org@gnu.org Original-Sender: bug-guile-bounces+guile-bugs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.lisp.guile.bugs:7488 Archived-At: David Kastrup writes: > * module/srfi/srfi-1.scm (reduce-right): Avoid use of drop-right in > connection with last as a single upfront reverse is more efficient and > simpler to understand. > > Signed-off-by: David Kastrup > --- > module/srfi/srfi-1.scm | 5 +---- > 1 file changed, 1 insertion(+), 4 deletions(-) > > diff --git a/module/srfi/srfi-1.scm b/module/srfi/srfi-1.scm > index 73d164a..6aa249a 100644 > --- a/module/srfi/srfi-1.scm > +++ b/module/srfi/srfi-1.scm > @@ -573,10 +573,7 @@ then that's the return value." > F is on two elements from LST, rather than one element and a given > initial value. If LST is empty, RIDENTITY is returned. If LST > has just one element then that's the return value." > - (check-arg procedure? f reduce) > - (if (null? lst) > - ridentity > - (fold-right f (last lst) (drop-right lst 1)))) > + (reduce f ridentity (reverse lst))) > > (define map > (case-lambda Looks good to me. Mark