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Worth noting XSLT is actually based on DSSSL, the Scheme-based document transformation and styling language of SGML. Core SGML already has "link processes" as a

Worth noting XSLT is actually based on DSSSL, the Scheme-based document transformation and styling language of SGML. Core SGML already has "link processes" as a means to associate simple transforms/renames reusing other markup machinery concepts such as attributes, but is also introducing a rather low-level automaton construct to describe context-dependent and stateful transformations (the kind of which would've be used for recto/verso rendering on even/odd print pages). I think it's interesting because XSLT, based on DSSSL, is already Turing-complete and thus the XML world lacked a "simple" sub-Turing transformation, templating, and mapping macro language that could be put in the hands of power users without going all the way to introduce a programming language requiring proper development cycles, unit testing, test harnesses, etc. to not inevitably explode in the hands of users. The idea of SGML is very much that you define your own little markup vocabulary for the kind of document you want to create at hand, including powerful features for ad-hoc custom Wiki markup such as markdown, and then create a canonical mapping to a rendering language such as HTML; a perspective completely lost in web development with nonsensical "semantic HTML" postulates and delivery of absurd amounts of CSS microsyntax.

user3939382 11mo ago
Completely correct and the operative phrase here is “absurd amounts” which actually captures our entire contemporary computing stack in almost every dimension that matters.
- tannhaeuser 11mo ago
  The entire point of markup attributes is to contain rendering hints that themselves aren't rendered to the user as such. Hell, angle-bracket markup itself was introduced to unify and put a limit to syntactic proliferation. But somehow "we" arrived at creating the monstrosity that is CSS and then even to put CSS and JS into inline element content with bogus special escaping and comment parsing rules rather than into attributes and external resources. The enormous proliferation of syntax and super-complicated layout models doesn't stop markup haters to cry wolf because entities (text macros) represent a security risk in markup however; go figure.
jeltz 11mo ago
But did it ever actually work in practice? As I remember it the XSLT backed websites still needed "absurd amounts of CSS microsyntac". You could not do everything you needed with XSLT so you needed to use both XSLT and CSS. Also coding in XSLT was generally painful, even more so than writing CSS (which I think is another poorly designed language). It is all well and good to talk about theoretical alternatives that would have been better but we are talking here about a concrete attempt which never worked beyond trivial examples. Why should we keep that alive because of something theoretical which in my opinion never existed?
- vbezhenar 11mo ago
  XSLT is template language. CSS is styling language. They have nothing to do with each other. You have data in some XML-based format. You write template using XSLT to transform that data into HTML. And then you use CSS to make that HTML look pretty. These technologies work very well with each other.
necovek 11mo ago
As a youngster entering the IT professional circles, I was enamoured with SGML: creating my own DTDs for humane entry for my static site generator, editing my SGML source document with Emacs sgml-mode. I worked on TEI and DocBook documents too (and was there something related to Dewey coding system for libraries?). However, processing fully compliant SGML, before you even introduce DSSSL into the picture, was a nightmare. With only one open source and at the same time the only fully compliant parser (nsgml), which was hard to build on contemporary systems, let alone run, really using SGML for anything was an exercise in frustration. As an engineering mind, I loved the fact you could create documents that are concise yet meaningful, and really express the semantics of your application as efficiently as possible. But I created my own parsers for my subset, and did not really support all of the features. HTML was also redefined to be an SGML application with 4.0. I originally frowned on XML as a simplification to make it work for computers vs for humans, but with XML, XSLT, Xpath... specs, even that was too complex for most. And I heavily used libxml2 and libxslt to develop some open source tooling for documentation, and it was full of landmines. All this to say that SGML has really spectacularly failed (IMO) due to sheer flexibility and complexity. And going for "semantic HTML" in lieu of SGML + DSSSL or XML + XSLT was really an attempt to find that balance of meaning and simplicity. It's the common cycle as old as software engineering itself.
- tannhaeuser 11mo ago
  > HTML was also redefined to be an SGML application with 4.0 Nope, it was intended as SGML from the get go; cf [1]. > SGML has really spectacularly failed (IMO) due to sheer flexibility and complexity HTML (and thus SGML) is the most used document language there ever has been, by far. [1]: https://info.cern.ch/hypertext/WWW/MarkUp/MarkUp.html https://info.cern.ch/hypertext/WWW/MarkUp/MarkUp.html
  - necovek 11mo ago
    I stand corrected: HTML was defined as an SGML application from the very first published version in 1993 (https://www.w3.org/MarkUp/draft-ietf-iiir-html-01.txt https://www.w3.org/MarkUp/draft-ietf-iiir-html-01.txt), but I know the original draft in 1990-91 was heavily SGML inspired even if it didn't really conform to the spec (nor provide a DTD). Thanks for pointing this out, it's funny how memory can play games on us :) While HTML is clearly the most used document markup language there has ever been, almost nobody is using an SGML-compliant parser to parse and process it, and most are not even bothering with the DTD itself; not to mention that HTML5 does not provide a DTD and really can't even be expressed with an SGML DTD. So while HTML used to be one of SGML "applications" (document types, along with a formal definition), on the web it was never treated as such, but as a very specific language that is inspired by SGML and only inspired by the spec too (since day 1, all browsers accepted "invalid" HTML and they still do). Ascribing the success to SGML is completely backwards, IMHO: HTML was successful despite it being based on SGML, and for all intents and purposes, majority never really cared about the relationship.

user3939382 11mo ago

Completely correct and the operative phrase here is “absurd amounts” which actually captures our entire contemporary computing stack in almost every dimension that matters.

tannhaeuser 11mo ago
The entire point of markup attributes is to contain rendering hints that themselves aren't rendered to the user as such. Hell, angle-bracket markup itself was introduced to unify and put a limit to syntactic proliferation. But somehow "we" arrived at creating the monstrosity that is CSS and then even to put CSS and JS into inline element content with bogus special escaping and comment parsing rules rather than into attributes and external resources. The enormous proliferation of syntax and super-complicated layout models doesn't stop markup haters to cry wolf because entities (text macros) represent a security risk in markup however; go figure.

jeltz 11mo ago

But did it ever actually work in practice? As I remember it the XSLT backed websites still needed "absurd amounts of CSS microsyntac". You could not do everything you needed with XSLT so you needed to use both XSLT and CSS. Also coding in XSLT was generally painful, even more so than writing CSS (which I think is another poorly designed language). It is all well and good to talk about theoretical alternatives that would have been better but we are talking here about a concrete attempt which never worked beyond trivial examples. Why should we keep that alive because of something theoretical which in my opinion never existed?

vbezhenar 11mo ago
XSLT is template language. CSS is styling language. They have nothing to do with each other. You have data in some XML-based format. You write template using XSLT to transform that data into HTML. And then you use CSS to make that HTML look pretty. These technologies work very well with each other.

necovek 11mo ago

As a youngster entering the IT professional circles, I was enamoured with SGML: creating my own DTDs for humane entry for my static site generator, editing my SGML source document with Emacs sgml-mode. I worked on TEI and DocBook documents too (and was there something related to Dewey coding system for libraries?). However, processing fully compliant SGML, before you even introduce DSSSL into the picture, was a nightmare. With only one open source and at the same time the only fully compliant parser (nsgml), which was hard to build on contemporary systems, let alone run, really using SGML for anything was an exercise in frustration. As an engineering mind, I loved the fact you could create documents that are concise yet meaningful, and really express the semantics of your application as efficiently as possible. But I created my own parsers for my subset, and did not really support all of the features. HTML was also redefined to be an SGML application with 4.0. I originally frowned on XML as a simplification to make it work for computers vs for humans, but with XML, XSLT, Xpath... specs, even that was too complex for most. And I heavily used libxml2 and libxslt to develop some open source tooling for documentation, and it was full of landmines. All this to say that SGML has really spectacularly failed (IMO) due to sheer flexibility and complexity. And going for "semantic HTML" in lieu of SGML + DSSSL or XML + XSLT was really an attempt to find that balance of meaning and simplicity. It's the common cycle as old as software engineering itself.

tannhaeuser 11mo ago
> HTML was also redefined to be an SGML application with 4.0 Nope, it was intended as SGML from the get go; cf [1]. > SGML has really spectacularly failed (IMO) due to sheer flexibility and complexity HTML (and thus SGML) is the most used document language there ever has been, by far. [1]: https://info.cern.ch/hypertext/WWW/MarkUp/MarkUp.html https://info.cern.ch/hypertext/WWW/MarkUp/MarkUp.html
- necovek 11mo ago
  I stand corrected: HTML was defined as an SGML application from the very first published version in 1993 (https://www.w3.org/MarkUp/draft-ietf-iiir-html-01.txt https://www.w3.org/MarkUp/draft-ietf-iiir-html-01.txt), but I know the original draft in 1990-91 was heavily SGML inspired even if it didn't really conform to the spec (nor provide a DTD). Thanks for pointing this out, it's funny how memory can play games on us :) While HTML is clearly the most used document markup language there has ever been, almost nobody is using an SGML-compliant parser to parse and process it, and most are not even bothering with the DTD itself; not to mention that HTML5 does not provide a DTD and really can't even be expressed with an SGML DTD. So while HTML used to be one of SGML "applications" (document types, along with a formal definition), on the web it was never treated as such, but as a very specific language that is inspired by SGML and only inspired by the spec too (since day 1, all browsers accepted "invalid" HTML and they still do). Ascribing the success to SGML is completely backwards, IMHO: HTML was successful despite it being based on SGML, and for all intents and purposes, majority never really cared about the relationship.