From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Sebastian Tennant Newsgroups: gmane.lisp.guile.user Subject: Dynamic variable binding Date: Wed, 12 Nov 2008 19:53:03 +0000 Message-ID: <8wro202o.fsf@vps203.linuxvps.org> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1226519637 9449 80.91.229.12 (12 Nov 2008 19:53:57 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 12 Nov 2008 19:53:57 +0000 (UTC) To: guile-user@gnu.org Original-X-From: guile-user-bounces+guile-user=m.gmane.org@gnu.org Wed Nov 12 20:54:58 2008 Return-path: Envelope-to: guile-user@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1L0Lni-0007dX-Sp for guile-user@m.gmane.org; Wed, 12 Nov 2008 20:54:55 +0100 Original-Received: from localhost ([127.0.0.1]:41468 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1L0Lmb-0001f3-1c for guile-user@m.gmane.org; Wed, 12 Nov 2008 14:53:45 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1L0LmD-0001Vp-8J for guile-user@gnu.org; Wed, 12 Nov 2008 14:53:21 -0500 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1L0LmC-0001VM-8u for guile-user@gnu.org; Wed, 12 Nov 2008 14:53:20 -0500 Original-Received: from [199.232.76.173] (port=53914 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1L0LmC-0001VH-56 for guile-user@gnu.org; Wed, 12 Nov 2008 14:53:20 -0500 Original-Received: from main.gmane.org ([80.91.229.2]:47382 helo=ciao.gmane.org) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1L0LmB-00019q-RS for guile-user@gnu.org; Wed, 12 Nov 2008 14:53:20 -0500 Original-Received: from list by ciao.gmane.org with local (Exim 4.43) id 1L0Lm5-0003zJ-01 for guile-user@gnu.org; Wed, 12 Nov 2008 19:53:13 +0000 Original-Received: from vps203.linuxvps.org ([91.186.7.203]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 12 Nov 2008 19:53:12 +0000 Original-Received: from sebyte by vps203.linuxvps.org with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 12 Nov 2008 19:53:12 +0000 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 35 Original-X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: vps203.linuxvps.org User-Agent: Gnus/5.110011 (No Gnus v0.11) Emacs/22.2 (gnu/linux) Cancel-Lock: sha1:XL7lOMTGMj4rCxRcMaeDP9yKHZk= X-detected-operating-system: by monty-python.gnu.org: GNU/Linux 2.6, seldom 2.4 (older, 4) X-BeenThere: guile-user@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: General Guile related discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: guile-user-bounces+guile-user=m.gmane.org@gnu.org Errors-To: guile-user-bounces+guile-user=m.gmane.org@gnu.org Xref: news.gmane.org gmane.lisp.guile.user:6890 Archived-At: Hi all, An elementary scheme problem from an elementary schemer... I need to create multiple variable bindings from a list of symbols. The value of the variables is unimportant. It's the 'names' of the variables that matter. In pseudo-scheme code: (map (lambda (v) (define (eval v) "foo") '(var1 var2 var3))) Clearly this won't work but I thought perhaps calling a macro in place of the 'define' would do it, but... guile> (define-macro (definer var val) `(define ,var ,val)) guile> (definer 'foo "bar") guile> foo ERROR: Unbound variable: foo ABORT: (unbound-variable) No doubt this fails for the same reason this does: guile> (define 'foo "bar") guile> foo ERROR: Unbound variable: foo ABORT: (unbound-variable) What exactly happens when you 'define' a symbol? Any tips/pointers much appreciated. Sebastian