From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Stefan Monnier Newsgroups: gmane.emacs.devel Subject: Re: ELisp futures and continuations/coroutines Date: Thu, 19 May 2011 11:15:08 -0300 Message-ID: References: <87fwogaxzb.fsf@stupidchicken.com> <87mxilezg8.fsf@lifelogs.com> <87boz0eov8.fsf@lifelogs.com> <87mxikrulm.fsf@lifelogs.com> <871uzw5asv.fsf@lifelogs.com> <878vu2ztua.fsf_-_@lifelogs.com> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: dough.gmane.org 1305814523 27256 80.91.229.12 (19 May 2011 14:15:23 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Thu, 19 May 2011 14:15:23 +0000 (UTC) Cc: emacs-devel@gnu.org To: Ted Zlatanov Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Thu May 19 16:15:18 2011 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([140.186.70.17]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1QN40U-0005fj-3v for ged-emacs-devel@m.gmane.org; Thu, 19 May 2011 16:15:18 +0200 Original-Received: from localhost ([::1]:44566 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QN40T-00009P-4n for ged-emacs-devel@m.gmane.org; Thu, 19 May 2011 10:15:17 -0400 Original-Received: from eggs.gnu.org ([140.186.70.92]:38439) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QN40Q-00009H-Kj for emacs-devel@gnu.org; Thu, 19 May 2011 10:15:15 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QN40P-0005O6-9U for emacs-devel@gnu.org; Thu, 19 May 2011 10:15:14 -0400 Original-Received: from fencepost.gnu.org ([140.186.70.10]:40570) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QN40P-0005O2-85 for emacs-devel@gnu.org; Thu, 19 May 2011 10:15:13 -0400 Original-Received: from 213-159-126-200.fibertel.com.ar ([200.126.159.213]:38957 helo=ceviche.home) by fencepost.gnu.org with esmtpsa (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1QN40O-00005T-Lc; Thu, 19 May 2011 10:15:12 -0400 Original-Received: by ceviche.home (Postfix, from userid 20848) id 13FB366230; Thu, 19 May 2011 11:15:08 -0300 (ART) In-Reply-To: <878vu2ztua.fsf_-_@lifelogs.com> (Ted Zlatanov's message of "Thu, 19 May 2011 08:46:21 -0500") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.0.50 (gnu/linux) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 3) X-Received-From: 140.186.70.10 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:139518 Archived-At: SM> That's a good idea. Kind of like a future. > Speaking of futures, can we have a general facility for those? > 1) a real "future" type > 2) a way to construct it and check if the value is available > 3) process sentinel tie-in Patches welcome (preferably Elisp-only for a start). > I'm sure much of this facility is either possible or already available > in ELisp, I just don't know the pieces and I think it would be very > convenient to provide a "future" type. WDYT? I don't think it's already available, nor do I think similar things are commonly used currently. > Similarly it would be very nice to provide continuations and coroutines > if those are not already possible. They don't need a top-level type > though, a lexical closure is sufficient I think. Please tell me how I'm > wrong :) Given the way we implement the stack call/cc is difficult to implement. But the concurrency branch should make it easy to have coroutines. Stefan