From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Rusi Newsgroups: gmane.emacs.help Subject: Re: Why is booleanp defined this way? Date: Fri, 17 Apr 2015 20:35:23 -0700 (PDT) Message-ID: References: <87twwemaxx.fsf@debian.uxu> <138bf565-898d-4b5a-8bea-eecd223c652b@googlegroups.com> <87d2322li0.fsf@debian.uxu> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 X-Trace: ger.gmane.org 1429328419 4440 80.91.229.3 (18 Apr 2015 03:40:19 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 18 Apr 2015 03:40:19 +0000 (UTC) To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Sat Apr 18 05:40:18 2015 Return-path: Envelope-to: geh-help-gnu-emacs@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 1YjJcA-0008VK-4l for geh-help-gnu-emacs@m.gmane.org; Sat, 18 Apr 2015 05:40:18 +0200 Original-Received: from localhost ([::1]:44396 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YjJc9-0002Ju-Je for geh-help-gnu-emacs@m.gmane.org; Fri, 17 Apr 2015 23:40:17 -0400 X-Received: by 10.66.142.196 with SMTP id ry4mr8071400pab.12.1429328123939; Fri, 17 Apr 2015 20:35:23 -0700 (PDT) X-Received: by 10.50.1.43 with SMTP id 11mr128737igj.8.1429328123904; Fri, 17 Apr 2015 20:35:23 -0700 (PDT) Original-Path: usenet.stanford.edu!m20no4265323iga.0!news-out.google.com!db6ni18639igc.0!nntp.google.com!m20no4265314iga.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail Original-Newsgroups: gnu.emacs.help In-Reply-To: Complaints-To: groups-abuse@google.com Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=117.195.40.192; posting-account=mBpa7woAAAAGLEWUUKpmbxm-Quu5D8ui Original-NNTP-Posting-Host: 117.195.40.192 User-Agent: G2/1.0 Injection-Date: Sat, 18 Apr 2015 03:35:23 +0000 Original-Xref: usenet.stanford.edu gnu.emacs.help:211519 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Original-Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.help:103801 Archived-At: On Saturday, April 18, 2015 at 8:41:19 AM UTC+5:30, Barry Margolin wrote: > Emanuel Berg wrote: > > > Rusi writes: > > > > >> I never used `booleanp' and I never experienced > > >> that the boolean built-in type was missing from my > > >> "ontology". > > > > > > If you how to write (and grok) an 'if' you have > > > boolean in your ontology. That you dont know that > > > you know is ok > > > > I know what a *boolean* is, just not why I would need > > a built-in data type to express it. > > It's not a built-in type. It's a conceptual type, like "list". Ha! Ha!! What a fantastic one-line summary-example of what I was trying to say! I always marvel at how Lisp puns on the word 'list': - Sometimes 'normal' lists -- like arrays in other languages - Sometimes heterogeneous -- like structs - Sometimes recursive structured -- aka trees - Sometimes homoiconic -- code=data - And yet at bottom they are just s-expressions -- the barest possible binary tree -- each internal node containing nothing but subtrees And so -- to expand a little on what you are saying: -- Getting lisp limited to the formal language definition is nothing more than getting the defs of car/cdr/null/nil/cons -- Getting lisp as a lisp programmer means getting all the above and more, making Eric Raymond's mystical sounding quote quite literal: | Lisp is worth learning for the profound enlightenment experience you will | have when you finally get it; that experience will make you a better | programmer for the rest of your days, even if you never actually use Lisp | itself a lot.