Subject: Re: returning from a function (Ex: Re: some small proposed changes to standard)
From: rpw3@rigden.engr.sgi.com (Rob Warnock)
Date: 1999/07/27
Newsgroups: comp.lang.lisp
Message-ID: <7njrck$60a4d@fido.engr.sgi.com>
Christopher B. Browne <cbbrowne@hex.net> wrote:
+---------------
| The W3C "HTML editor," Amaya... can only create "valid" HTML.
| Unfortunately, it is almost unusable as such.
...
| a) Godel's "Incompleteness" theorem.  
...
| I would suggest the connection that it may be *impossible* to create
| an editor that *guarantees* that (for instance) an SGML document is
| valid at every step.
+---------------

Interesting, but I think your analogy is slightly off. Better might
be to equate the legal steps in the editor to theorems (or maybe even
better, rules of inference) in the proof system. Then you'd get a
statement like this:

  While it is certainly possible to create an editor that guarantees
  that an initially valid SGML document remains valid after every
  subsequent allowed editing step, Godel's Proof suggests that there
  will always be some valid SGML documents which it is impossible
  to create using such an editor.


-Rob

-----
Rob Warnock, 8L-855		rpw3@sgi.com
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