Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!cs.utexas.edu!uunet!mcvax!ukc!etive!aiai!jeff
From: jeff@aiai.uucp (Jeff Dalton)
Newsgroups: comp.lang.lisp
Subject: Re: (Long) Code as data (Lisp's syntax - Answer to Stephen Knight).
Message-ID: <538@skye.ed.ac.uk>
Date: 14 Jun 89 13:44:44 GMT
References: <2727@ski.cs.vu.nl> <1350022@otter.hpl.hp.com>
Sender: news@aiai.ed.ac.uk
Reply-To: jeff@aiai.uucp (Jeff Dalton)
Organization: AIAI, University of Edinburgh, Scotland
Lines: 32

In article <1350022@otter.hpl.hp.com> sfk@otter.hpl.hp.com (Stephen Knight) writes:
>> Another thing, of course, is
>> whether one should have many data types in the first place, but once they
>> are there they should be denotable.
>                 ^^^^^^^^^^^^^^^^^^^
>There's no need.  Why clutter up the language?

So that values of those types can be printed and read.

>> I can only interpret this if I assume that you indeed were confused 

>Well, its a fair cop, guv.  I forgot at the time of writing that '|' is not
>a quote at the semantic but only at the syntactic level.  This doesn't
>actually affect the underlying argument.

I think it does affect the underlying argument.  

>> All literals *may* be quoted already, and *only* literals can be quoted.
>> Self-evaluating expressions are an optional addition for ease of writing.

>And the ease of writing is at the expense of machine tractability as the
>two programs 0 and '0 are equivalent.  I frequently find myself writing
>canonisation programs to eliminate this (and other) ambiguities.

I would be surprised if many people found this to be a problem.

>Yes, I've seen it happen.  I've used Lisps with multiple syntaxes & no one,
>including me, switched.  I tried to outline the reasons in my first letter.

But you're proposing a Lisp with multiple syntaxes.  I've read your
various letters and don't see how your proposal avoids the problems
you've mentioned.