http://www.albany.edu/hammond/gellmu/mui/October 22, 1999 Last reprocessing William F. HammondUniv at Albany: W. F. Hammond: The GELLMU Archivesetlengthtopmargin-30bpsetlengthtextheight696bp

&SecRef-1;SU-1The Value of a Like Markup User Interface for XMLA markup user interface (MUI) for an XML language (formally XML application) is a markup language that admits a welldefined translation to the XML languageRecent discussions in news:comp.text.tex show that at least two of us are thinking about MUIs for like XML languages Jonathan Fine has been working on a rofflike MUI that he calls Active TeX, and I have been working on a like MUI that I call GELLMUAs I use the acronym MUI, I do intend it to be reminiscent of the acronym GUI for graphical user interface Both GUIs and MUIs have the intention of making life easier, or perhaps at least more familiar, for some authors An MUI, unlike typical GUIs, has the possibility of giving the author full and rigorous control over contentFurthermore, an MUI in the style of a preexisting nonXML markup offers a convenient avenue for prototyping a new XML language to model the markup practice in the preexisting markupBeyond that, it offers a route for conversion of legacy archives in the preexisting markup to XML languages with minimal human interventionPlease allow me to say a bit more about what I have in mind for GELLMU

&SecRef-2;SU-2The Basic GELLMU Processing DesignThe things that I have on hand, aside from are: GNU Emacs, version 20 (I believe that version 19 is OK.) James Clark's nsgmls, a part of his SP My processing setup is the following: Syntactic translation from like markup to SGML My Elisp processor, which can be run interactively in GNU Emacs or in batch mode, performs syntactic translation to convert like markup to an SGML language (formally, application) The syntactic translator is largely ignorant of command names Whatever command names are used become the names of SGML elements There is a standard way to convert multiple argumentoption sequences This processing stage traps syntax errors (It will fail to detect an even number of missing characters; but this error will show in the next stage.) Validating parse of the SGML language At the validation stage the difference between SGML and XML is significant if one wants to have math mode be a global toggle since that may be modeled robustly only using SGML exclusions A validating parse is made using nsgmls Of course, the language definition, i.e., SGML application definition, is crucial It is contained in an SGML declaration and in an SGML document type definition (DTD)The language definition that I am using is the heart of my personal production system But I regard it only as didactic in the larger scheme of things Others will certainly want things that I do not wantAs far as it goes, it models rather closely in some ways and rather loosely in other ways Where it departs from close modeling, the reason is usually related to having a document structure that is not printcentricThe validating parse traps errors in language use Downtranslation to XML This is done with the program called sx in the family of SP processors While it is possible to recover an equivalent SGML document from the downtranslated XML, it is not possible under the XML umbrella to have as precise a language definition as under the wider SGML umbrella That said, either form may be run through a processor that serves to enforce a tighter language definition SGML processing This can go anywhere that is sane for the language definition One can use any programming language, but it helps to have a basic SGML library on hand I am using David Megginson's SGMLS.pm, a Perl 5 library, and its interface sgmlspl In my personal production system I routinely format GELLMU articles for both and HTML Invalid HTML and error messages from represent bugs in my processors, which I always repair as soon as possible There may be box size complaints from ; they represent authoring content errors These two formatters work either on the SGML or the XML version of an articleAt present my personal production language definition is not fully uptospeed for journal articles nor for translation to XHTMLwithMathML, but it is serving me well for my classes It gives me a sane way to have course handouts and web offerings in a bulletproof way from a single source At this time I simply cannot assume that more than about a third of my students have easy access to PDF readers So I feel constrained to give them simple HTML with very limited pseudoTeX for mathOther formattings for GELLMU article that should be possible include translations to (1) DocBook, (2) TEI, and (3) Texinfo, though suboptimally so long as math is not available These are not small jobs, and I may never undertake any of them (Any project that undertakes to format an XML language in Texinfo should give serious consideration first to modeling Texinfo as an XML It would also be desirable to minimize Info bifurcation in XTexinfo and to provide math for XTexinfo.)If a time arrives when I can assume that threefourths of my students have outofthebox browsers for XHTMLwithMathML, then I should be able to format the original GELLMU source directly for that if by that time I am not able to squeeze it out of carefullyset LaTeX4 (I exaggerate somewhat In principle, I need to provide some math symbol declarations in the sources, and math symbol declaration handling is not yet present in my setup.)

&SecRef-3;SU-3About this documentThis document was prepared as a GELLMU article A copy of the HTML version of this document is available on the web at http://www.albany.edu/hammond/gellmu/mui/ along with a full list of anchored versions as follows: GELLMU source: mui.glmSGML, article document type: mui.sgmlXML, article document type: mui.xmlformatting in : mui.ltxDVI made from : mui.dviPDF made from : mui.pdfformatting in HTML: mui.html