Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!zaphod.mps.ohio-state.edu!rpi!uupsi!sunic!liuida!prosys!ath
From: ath@prosys.se (Anders Thulin)
Newsgroups: comp.text
Subject: Re: SGML question
Keywords: SGML, ambiguity
Message-ID: <583@helios.prosys.se>
Date: 5 Sep 90 06:04:53 GMT
References: <555@helios.prosys.se> <146@thor.UUCP> <582@helios.prosys.se> <141829@sun.Eng.Sun.COM>
Organization: Telesoft AB, Teknikringen 2A, S-583 30 Linkoping, Sweden
Lines: 52

In article <141829@sun.Eng.Sun.COM> tut@cairo.Sun.COM (Bill "Bill" Tuthill) writes:

>3. It doesn't deal with graphics, tables, or equations (is that 5 strikes?).

Graphics, no. Although graphics should probably be treated as non-SGML
data, which SGML can handle.

Tables it does provide for. That is, SGML permits you to mark up a
table.  The actual formatting is left to a 'processor', which is
supposed to do what you want in some way. So, provided that you have
this 'processor' you can do tables. I understand the word 'processor'
to mean a formatting program, e.g. troff.

Equations is almost the same thing. SGML permits text (entities?) to
be written in a 'notation', which then is interpreted by some
'notation translator'. I believe there is a registered BSI notation
standard which could be used. Alternatively, TeX notation could
probably be used as well. 

You are right that SGML doesn't provide these capabilities directly.
But a SGML parser/translator should not choke on them either. It
should just pass the buck to something who does better.

>   It only provides text portability, which ASCII does more elegantly.

ASCII isn't much of a help if I want to insert a Swedish { in the
text.  (That '{', of course, is an 'a' with an umlaut accent). Nor is
ASCII very good at indicating italics or boldface.

Some further coding conventions are required if I want to be able to
use these 'signs'. SGML is one way of making such conventions.

>My mind is open, but so far SGML proponents have said nothing to make me
>change my mind.  We all want document portability, but I don't think we'll
>ever see it from SGML.  And if SGML isn't supposed to provide document
>portability, just what problem is it supposed to solve?

Document markup. I think SGML solves that, although perhaps not as
neatly as I would wish it did.

The interchange (or portability) part should be solved by the SDIF
standard.  I haven't seen it, so I can't swear to it. 

--

It would be interesting to hear from anyone with hands-on experience
with SGML products if they are capable of handling graphics, equations
and things like that, and how well they do.

-- 
Anders Thulin       ath@prosys.se   {uunet,mcsun}!sunic!prosys!ath
Telesoft Europe AB, Teknikringen 2B, S-583 30 Linkoping, Sweden