Path: utzoo!attcan!uunet!tut.cis.ohio-state.edu!pt.cs.cmu.edu!o.gp.cs.cmu.edu!andrew.cmu.edu!mss+ From: mss+@andrew.cmu.edu (Mark Sherman) Newsgroups: comp.text.sgml Subject: Re: What about the DTD Message-ID: Date: 21 Oct 90 19:35:15 GMT Organization: Information Technology Center, Carnegie Mellon, Pittsburgh, PA Lines: 37 There is no substantive difference between the granularity of ODA's specific logical structures and SGML's tagged documents. Both are essententially trees: nodes, edges and leaves. Both allow and neither one requires that, say, a chapter or a word be a piece of the structure. What else is there to say? Since SGML has no notion of formatting or presentation, it is not meaningful to compare any SGML facility with ODA's layout facility. We successfully interchanged processable documents w/o any specific layout structure. Arguments about layout facilities are red herrings. There are some differences between ODA's generic logical structure and SGML's DTD, but both have more complexity than most documents use. Before you say how easy it is to search SGML text, are you expecting all of the tags to be explicit (or expecting all of them to be implicit)? Depending on the application, the lack of tags makes searching useless (while in other applications their presence gets in the way). What about multiple revisions? Just searching for a string doesn't tell you if it is really in the document -- you've got to parse the structure to see when it applies. I've heard a lot of things about EDI, and its relationship to both ODA and SGML. For something which apparently is very big, I don't see any discussions of it on Usenet or Internet. Am I not looking in the right place? I can "cheat" in ODA as well as SGML, and say that I'll only use it one way, which can make life easier. But as an implementor of either a SGML or ODA conforming system, I have to handle everything by the book (the exact book depends on whether its a particular SGML application, ODA DAP, etc, etc). If you want to make your own subset and then exclaim how wonderful the standard is, I suggest you read the a recent editoral in (I think) CD ROM End User with the title something of the form "SGML-like is not SGML". -Mark