From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Michael Heerdegen Newsgroups: gmane.emacs.devel Subject: Re: Streams: add stream-delay and streams of directory files Date: Fri, 04 Mar 2016 13:15:50 +0100 Message-ID: <87k2licubt.fsf@web.de> References: <87pow3mkyq.fsf@web.de> <87r3gjt2ay.fsf@petton.fr> <87si0ijc6w.fsf@web.de> <87twknmxln.fsf@petton.fr> <87ziufwpk3.fsf@web.de> <87r3frmvfo.fsf@petton.fr> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1457093784 10204 80.91.229.3 (4 Mar 2016 12:16:24 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Fri, 4 Mar 2016 12:16:24 +0000 (UTC) To: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri Mar 04 13:16:16 2016 Return-path: Envelope-to: ged-emacs-devel@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 1aboeV-0002lr-JB for ged-emacs-devel@m.gmane.org; Fri, 04 Mar 2016 13:16:15 +0100 Original-Received: from localhost ([::1]:40763 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aboeU-0003P4-Q2 for ged-emacs-devel@m.gmane.org; Fri, 04 Mar 2016 07:16:14 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:50238) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aboeM-0003Hg-Sl for emacs-devel@gnu.org; Fri, 04 Mar 2016 07:16:10 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aboeJ-0001QD-Np for emacs-devel@gnu.org; Fri, 04 Mar 2016 07:16:06 -0500 Original-Received: from plane.gmane.org ([80.91.229.3]:56913) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aboeJ-0001Q7-HI for emacs-devel@gnu.org; Fri, 04 Mar 2016 07:16:03 -0500 Original-Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1aboeH-0002d8-No for emacs-devel@gnu.org; Fri, 04 Mar 2016 13:16:01 +0100 Original-Received: from dslb-094-218-223-112.094.218.pools.vodafone-ip.de ([94.218.223.112]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 04 Mar 2016 13:16:01 +0100 Original-Received: from michael_heerdegen by dslb-094-218-223-112.094.218.pools.vodafone-ip.de with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 04 Mar 2016 13:16:01 +0100 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 28 Original-X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: dslb-094-218-223-112.094.218.pools.vodafone-ip.de User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.0.92 (gnu/linux) Cancel-Lock: sha1:9s83oVWUa5getUejDmWTJvwH8X0= X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 80.91.229.3 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:200906 Archived-At: Artur Malabarba writes: > Sorry if this is a silly question, but isn't stream-delay just > reimplementing thunk.el (the functionality that stream itself is > built-on)? Yes, that's a very congruous question. Let me add to Nicolas comment: The semantics is very similar to that of `thunk-delay', and it serves the same purpose at the end: delaying an expression. The idea behind `stream-delay' was to transfer the idea of delaying to the level of streams: `stream-delay' takes an expression E that must (later) evaluate to a stream S, and returns another stream S' (and not a thunk). And unlike `thunk-delay', when referencing an element of S', E is _implicitly_ evaluated to get S. I just defined that because it made sense for defining `stream-of-directory-files'. Maybe you have a nicer idea for reaching the same goal...? Regards, Michael.