Re: [xml-dev] GenCode

["Rick Jelliffe" <ricko@allette.com.au>]

From: "Simon St.Laurent" <simonstl@simonstl.com>

> I was looking the other day for information about GenCode, but most of
> what I can find describes it as a predecessor to SGML that got folded
> into the main SGML effort.  

There is some information in Charles Goldfarb's SGML Handbook p 567.
He says "Many credit the start of the generic coding movement
to ... William Tunnicliffe[2]" (of the GCA) who gave a paper in 1967 on
"the separation of the information contents of documents from their format."
 
IBM's GML advanced Gencoding: "Instead of a simple tagging scheme however,
GML introduced the concept of a formally defined document type with
an explicit nested element structure."

Goldfarb sees "generic coding" as systems where only the GI
is used for processing (e.g. SCRIBE). He (p10) contrasts this with
generalized markup where there are IDs and secondary
attributes which also can be used. Also, the notion of "rigorous
markup" is not in gencoding (i.e. that you should use a grammar)
One reason for Goldfarb's move from generic coding to generalized
markup was that "unlike (the other pioneers) my chief motivation was 
information retrieval, not typesetting."[1]

The Gencoding and GML efforts got together in 1978 to start on SGML.
The first draft of SGML was released in 1980 and subject to 6 years of
review and adoption until the final text of the standard was released. 

It also added things like short references (i.e. so that "[" = "<citation"> or
whatever) and the dreaded CONCUR.  Dave Peterson made an interesting comment
recently, that SGML DTDs originally used element syntax, but that
it proved so unwieldy they moved to a custom syntax: the road
that RELAX NG compact syntax has taken (and the attempts to make 
a nice syntax for WXS) is well-trodden.

> While I'm aware of that contribution, I'm curious what GenCode itself
> was trying to accomplish.  My rapidly-fading memory suggests that a
> single tag set was a key (though not accomplished) goal, and someone was
> even speaking of "the shadow of GenCode", though I'm no longer sure in
> what context.

The various papers on Charles' site http://www.sgmlsource.com/history/index.htm
have good information and references. A nice page also is
http://www.renater.fr/Video/2002ATHENS/P/DC/History/all.htm
 
Cheers
Rick Jelliffe 

[1] http://www.sgmlsource.com/history/jasis.htm
[2] http://xml.coverpages.org/tunnicliffe.html  for a nice obituary