From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Ted Zlatanov Newsgroups: gmane.emacs.devel Subject: Re: general lazy list facility for Emacs Lisp? Date: Wed, 23 Mar 2011 12:12:34 -0500 Organization: =?utf-8?B?0KLQtdC+0LTQvtGAINCX0LvQsNGC0LDQvdC+0LI=?= @ Cienfuegos Message-ID: <87oc51rcal.fsf@lifelogs.com> References: <87pqphswn3.fsf@lifelogs.com> <877hbpzsy8.fsf@member.fsf.org> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: dough.gmane.org 1300900392 18048 80.91.229.12 (23 Mar 2011 17:13:12 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Wed, 23 Mar 2011 17:13:12 +0000 (UTC) To: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Wed Mar 23 18:13:07 2011 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Q2RcJ-00019U-8N for ged-emacs-devel@m.gmane.org; Wed, 23 Mar 2011 18:13:07 +0100 Original-Received: from localhost ([127.0.0.1]:57874 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Q2RcI-0004NC-Ki for ged-emacs-devel@m.gmane.org; Wed, 23 Mar 2011 13:13:06 -0400 Original-Received: from [140.186.70.92] (port=57070 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Q2Rc9-0004F8-Bo for emacs-devel@gnu.org; Wed, 23 Mar 2011 13:13:02 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Q2Rc7-0005QB-RZ for emacs-devel@gnu.org; Wed, 23 Mar 2011 13:12:57 -0400 Original-Received: from lo.gmane.org ([80.91.229.12]:49736) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Q2Rc7-0005Q7-M8 for emacs-devel@gnu.org; Wed, 23 Mar 2011 13:12:55 -0400 Original-Received: from list by lo.gmane.org with local (Exim 4.69) (envelope-from ) id 1Q2Rc3-0000xM-D6 for emacs-devel@gnu.org; Wed, 23 Mar 2011 18:12:51 +0100 Original-Received: from 38.98.147.130 ([38.98.147.130]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 23 Mar 2011 18:12:51 +0100 Original-Received: from tzz by 38.98.147.130 with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 23 Mar 2011 18:12:51 +0100 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 21 Original-X-Complaints-To: usenet@dough.gmane.org X-Gmane-NNTP-Posting-Host: 38.98.147.130 X-Face: bd.DQ~'29fIs`T_%O%C\g%6jW)yi[zuz6; d4V0`@y-~$#3P_Ng{@m+e4o<4P'#(_GJQ%TT= D}[Ep*b!\e,fBZ'j_+#"Ps?s2!4H2-Y"sx" User-Agent: Gnus/5.110016 (No Gnus v0.16) Emacs/24.0.50 (gnu/linux) Cancel-Lock: sha1:J/UIAs257mnajVdkFD+k6D+xXZ8= X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 3) X-Received-From: 80.91.229.12 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:137584 Archived-At: On Wed, 23 Mar 2011 17:45:35 +0100 Tassilo Horn wrote: TH> Ted Zlatanov writes: >> Is there a package for general lazy list management in Emacs Lisp? TH> What's a lazy list? Something like a LazySeq in Clojure, that is, a TH> possibly infinite sequence of things that are only calculated when TH> actually consumed ("realized")? TH> If that's what you mean, I think the answer is no. Yes, that's what I mean. In Haskell such lists are simply part of the core language; Perl 5 can hack them together with list accessors; Perl 6 has them in the core too... I think "lazy list" is a popular term for the general facility? I'm surprised no one has needed them, whatever the name :) Slightly related: is there a general memoization package or standard approach to memoizing functions? Ted