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From: "Pascal J. Bourguignon" <pjb@informatimago.com>
To: help-gnu-emacs@gnu.org
Subject: Re: why are there [v e c t o r s] in Lisp?
Date: Mon, 19 Oct 2015 02:45:10 +0200	[thread overview]
Message-ID: <87mvvfadpl.fsf@kuiper.lan.informatimago.com> (raw)
In-Reply-To: mailman.581.1445203060.7904.help-gnu-emacs@gnu.org

Robert Thorpe <rt@robertthorpeconsulting.com> writes:

> Emanuel Berg <embe8573@student.uu.se> writes:
>> Now that I know it isn't so I don't think the
>> syntax is bad. Actually, I'm curious about CL and
>> using the industrial Lisps to do "real" programs,
>> where types, data structures, memory usage, come to
>> play once again.
>
> There's one thing that Pascal didn't mention directly....  In some cases
> having literal syntax in Lisp is more important than in other
> languages.  In Lisp we have the function "read" which can read in
> anything that has a read syntax.  Let's say you have a program that has
> an data file format.  That file can be stored using "print" and
> read-back using "read".  For example, configuration could be stored as a
> list.  That list could contain other lists, strings and vectors.  Read
> and print eliminate the need to write a parser.  As a side-effect they
> may make the file human readable.  That makes having a vector or array
> syntax more useful.  Let's say the program is a CAD package and it's
> storing a 3D model.  That would use a lot of arrays.  If Lisp had no
> literal array syntax then lists would have to be used, then converted to
> arrays later.  That could be very inefficient for large models.

Indeed, and this is why there are reader macros, print-object, (and also
make-load-form and make-load-form-saving-slots) in CL: the language
doesn't provide a reader syntax for all its data types because there
aren't enough characters in the standard character set ;-) but it
provides the user to define its own reader syntaxes, for predefined lisp
classes and for user defined lisp classes.

-- 
__Pascal Bourguignon__                 http://www.informatimago.com/
“The factory of the future will have only two employees, a man and a
dog. The man will be there to feed the dog. The dog will be there to
keep the man from touching the equipment.” -- Carl Bass CEO Autodesk


       reply	other threads:[~2015-10-19  0:45 UTC|newest]

Thread overview: 56+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <mailman.581.1445203060.7904.help-gnu-emacs@gnu.org>
2015-10-19  0:45 ` Pascal J. Bourguignon [this message]
     [not found] <mailman.428.1444957396.7904.help-gnu-emacs@gnu.org>
2015-10-16  1:51 ` why are there [v e c t o r s] in Lisp? Pascal J. Bourguignon
2015-10-16  2:31   ` Emanuel Berg
2015-10-16  2:29     ` Random832
2015-10-16  2:51       ` Emanuel Berg
2015-10-16  2:56         ` Random832
2015-10-16 23:30           ` Emanuel Berg
     [not found]           ` <mailman.482.1445037713.7904.help-gnu-emacs@gnu.org>
2015-10-17  1:55             ` Pascal J. Bourguignon
2015-10-17  4:47               ` Emanuel Berg
     [not found]               ` <mailman.494.1445057637.7904.help-gnu-emacs@gnu.org>
2015-10-17 15:25                 ` Pascal J. Bourguignon
2015-10-17 21:12                   ` Emanuel Berg
     [not found]                   ` <mailman.519.1445115776.7904.help-gnu-emacs@gnu.org>
2015-10-18  1:08                     ` Pascal J. Bourguignon
     [not found]         ` <mailman.432.1444964227.7904.help-gnu-emacs@gnu.org>
2015-10-16  3:57           ` Pascal J. Bourguignon
2015-10-16  4:17             ` Random832
     [not found]             ` <mailman.434.1444970033.7904.help-gnu-emacs@gnu.org>
2015-10-16  5:16               ` Pascal J. Bourguignon
     [not found]   ` <mailman.429.1444962165.7904.help-gnu-emacs@gnu.org>
2015-10-16  3:31     ` Pascal J. Bourguignon
2015-10-16 23:46       ` Emanuel Berg
     [not found]       ` <mailman.483.1445038647.7904.help-gnu-emacs@gnu.org>
2015-10-17  2:04         ` Pascal J. Bourguignon
2015-10-17  4:40           ` Random832
2015-10-17  5:00             ` Emanuel Berg
2015-10-17  4:40           ` Emanuel Berg
     [not found]           ` <mailman.491.1445056308.7904.help-gnu-emacs@gnu.org>
2015-10-17  5:53             ` Barry Margolin
2015-10-17 15:16             ` Pascal J. Bourguignon
2015-10-17 21:06               ` Emanuel Berg
     [not found]               ` <mailman.518.1445115463.7904.help-gnu-emacs@gnu.org>
2015-10-18  1:07                 ` Pascal J. Bourguignon
2015-10-18 12:32                   ` Emanuel Berg
     [not found]                   ` <mailman.551.1445171034.7904.help-gnu-emacs@gnu.org>
2015-10-18 12:55                     ` Pascal J. Bourguignon
2015-10-18 14:28                       ` Emanuel Berg
2015-10-18 21:17                         ` Robert Thorpe
     [not found]                       ` <mailman.557.1445177952.7904.help-gnu-emacs@gnu.org>
2015-10-18 19:48                         ` Barry Margolin
2015-10-18 21:25                           ` Emanuel Berg
2015-10-18 21:39                             ` Random832
2015-10-19  0:46                         ` Pascal J. Bourguignon
2015-10-17  5:56           ` Barry Margolin
2015-10-17 15:06             ` Emanuel Berg
2015-10-16 13:32 ` Barry Margolin
2015-10-16 23:47   ` Emanuel Berg
2015-10-16  1:12 Emanuel Berg
2015-10-17  1:11 ` Aurélien Aptel
2015-10-17  4:22   ` Emanuel Berg
2015-10-17  7:58   ` Jude DaShiell
2015-10-19 16:33     ` Nick Dokos
     [not found]   ` <mailman.490.1445055179.7904.help-gnu-emacs@gnu.org>
2015-10-17 15:09     ` Pascal J. Bourguignon
     [not found] ` <mailman.488.1445044303.7904.help-gnu-emacs@gnu.org>
2015-10-17  2:22   ` Pascal J. Bourguignon
2015-10-17  4:56     ` Emanuel Berg
2015-10-17  5:49       ` Barry Margolin
2015-10-17 15:04         ` Emanuel Berg
     [not found]         ` <mailman.506.1445093727.7904.help-gnu-emacs@gnu.org>
2015-10-17 15:20           ` Pascal J. Bourguignon
2015-10-17 15:38             ` Emanuel Berg
     [not found]             ` <mailman.511.1445095810.7904.help-gnu-emacs@gnu.org>
2015-10-17 16:01               ` Javier
2015-10-17 16:03                 ` Javier
2015-10-17 16:34                 ` Pascal J. Bourguignon
2015-10-17 21:18                   ` Emanuel Berg
2015-10-17 16:15               ` Pascal J. Bourguignon
2015-10-17 21:37                 ` Emanuel Berg
2015-10-17 15:18       ` Pascal J. Bourguignon

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