From mboxrd@z Thu Jan 1 00:00:00 1970 Path: main.gmane.org!not-for-mail From: Marius Vollmer Newsgroups: gmane.lisp.guile.devel Subject: Re: comments on new-model.txt Date: 10 Sep 2002 00:55:08 +0200 Sender: guile-devel-admin@gnu.org Message-ID: <877khuydrn.fsf@zagadka.ping.de> References: <02090420222526.19624@locke.free-expression.org> <87n0qw45p4.fsf@zagadka.ping.de> <0209081847342E.19624@locke.free-expression.org> NNTP-Posting-Host: localhost.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: main.gmane.org 1031612238 5760 127.0.0.1 (9 Sep 2002 22:57:18 GMT) X-Complaints-To: usenet@main.gmane.org NNTP-Posting-Date: Mon, 9 Sep 2002 22:57:18 +0000 (UTC) Cc: guile-devel@gnu.org Return-path: Original-Received: from monty-python.gnu.org ([199.232.76.173]) by main.gmane.org with esmtp (Exim 3.35 #1 (Debian)) id 17oXT3-0001Um-00 for ; Tue, 10 Sep 2002 00:57:17 +0200 Original-Received: from localhost ([127.0.0.1] helo=monty-python.gnu.org) by monty-python.gnu.org with esmtp (Exim 4.10) id 17oXSx-0005XG-00; Mon, 09 Sep 2002 18:57:11 -0400 Original-Received: from list by monty-python.gnu.org with tmda-scanned (Exim 4.10) id 17oXSZ-0005Ta-00 for guile-devel@gnu.org; Mon, 09 Sep 2002 18:56:47 -0400 Original-Received: from mail by monty-python.gnu.org with spam-scanned (Exim 4.10) id 17oXSX-0005TO-00 for guile-devel@gnu.org; Mon, 09 Sep 2002 18:56:47 -0400 Original-Received: from dialin.speedway42.dip35.dokom.de ([195.138.42.35] helo=zagadka.ping.de) by monty-python.gnu.org with smtp (Exim 4.10) id 17oXSX-0005SX-00 for guile-devel@gnu.org; Mon, 09 Sep 2002 18:56:45 -0400 Original-Received: (qmail 28201 invoked by uid 1000); 9 Sep 2002 22:55:08 -0000 Original-To: Lynn Winebarger In-Reply-To: <0209081847342E.19624@locke.free-expression.org> Original-Lines: 35 User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.2 Errors-To: guile-devel-admin@gnu.org X-BeenThere: guile-devel@gnu.org X-Mailman-Version: 2.0.11 Precedence: bulk List-Help: List-Post: List-Subscribe: , List-Id: Developers list for Guile, the GNU extensibility library List-Unsubscribe: , List-Archive: Xref: main.gmane.org gmane.lisp.guile.devel:1321 X-Report-Spam: http://spam.gmane.org/gmane.lisp.guile.devel:1321 Lynn Winebarger writes: > So, we have two SCM types, ilocs and variables (actually > variable bindings, but we can leave that for later). ilocs always > look up their values in the data environment of their closure, and > variables are just pointers to a storage location. An extloc would > be like an iloc (that is, a frame offset and distance in a frame), > but would be stored in a cell where the second word pointed to the > data environment to look it up in (the first word would contain the > frame offset and distance). What use would be an extloc? Do you want to export lexical variables? Or would they be useful for hygienic macro expansion? Can you give example code that illustrates their use? > Likewise an extvarref would contain both the pointer to the binding > and some way of identifying what top-level environment it's from. If we need to, we could find the originating module for a imported variable also from the module that the current code is executed in. This would be slower, but we would not need the extra pointer in extvarrefs or variables. > This would be a convenient way to represent imported variables. The > only concrete reason I can offer for including a pointer (of some > form) to the top level environment of an external variable (actually > any top-level variable) is for ones that aren't bound at the time of > parsing (recalling that correct macro expansion can't be lazy in the > presence of side-effects, as some of the syntax-case examples I've > been posting should demonstrate). What would you do with that pointer? -- GPG: D5D4E405 - 2F9B BCCC 8527 692A 04E3 331E FAF8 226A D5D4 E405 _______________________________________________ Guile-devel mailing list Guile-devel@gnu.org http://mail.gnu.org/mailman/listinfo/guile-devel