Re: [xml-dev] Is the set of languages expressible using XML asuperset of

Hi Stephen,

concerning those "implicit" triples, everything becomes simple, uniform and clear by a couple of assumptions: (1) The mapping of document node to triples is not a push transformation, but a pull transformation, that is, the semantic model is fed with what it asks for. (2) "Feeding" the semantic model means applying XPath expressions to the input document - any XPath expressions you choose. As a consequence, nothing is explicit or implicit, as the only difference is the choice of XPath expression.

The idea of defining a schema in terms of semantic triples is very attractive and would be very promising, if minds (especially influential ones) were less obsessed with history and appearance, more focused on content and potential.

Kind regards,

Hans-Jürgen

Am Montag, 24. Januar 2022, 18:07:13 MEZ hat Stephen D Green <stephengreenubl@gmail.com> Folgendes geschrieben:

Hi Hans-Juergen

I like that comment. I was a contributor a decade ago to a paper on the subject. From that study I would make two points:

1. A lot of the set of triples will be implicit (such as significance, if any, of sequences, parent-child relationships, sibling-relationships, container complex types, attribute-element relationships, code values, derivations, etc. Some will even be tacit or heuristic.

2. Because of 1. it might be possible to avoid tacit and implicit semantics altogether by using semantic triples to define the schema and making the semantic definition normative then using design rules to generate the schema.

Best Regards

Stephen D Green

On Mon, 24 Jan 2022 at 16:00, Hans-Juergen Rennau <hrennau@yahoo.de> wrote:

There must be some way out of here, said the joker to the thief, there's too much confusion, I can't get no relief.*

If we accept the point of view that a set of RDF triples (R) is an unequivocal statement of semantics, the semantics of an XML document - as well as of a JSON document - is implied by the specification of a mapping M of a given document node D to a set of triples:
D + M => R

Such mapping should be specified using a new mapping language, consuming XDM document nodes and emitting RDF triples. To define it would be a matter of diligence, more than anything else. (Given the availability of XPath.) It is a pity that the W3C did not take that path.

* https://www.youtube.com/watch?v=bT7Hj-ea0VE

Am Montag, 24. Januar 2022, 10:27:39 MEZ hat Ihe Onwuka <ihe.onwuka@gmail.com> Folgendes geschrieben:

On Mon, Jan 24, 2022 at 3:29 AM Michael Kay <mike@saxonica.com> wrote:

An XML language can be created to express Bookstores.

.....which allied with an XML schema can semantically represent books, magazines and newspapers as types of Publication (remember). A JSON document with or without an accompanying JSON Schema cannot do that.

Of course it can, it just does it differently. Instead of capturing the type of publication using the element name, you capture it with an extra attribute/property named "publicationType". You can argue about which representation is "better" (for example, better at conveying the semantics to the human reader), but they both capture the same information -- and neither conveys any semantics to the human reader unless they know what the element and attribute names are supposed to mean.

You can argue about whether they mean the same thing at all as would be the case if "publicationType" is a JSON array that therefore permits multiple values.

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Stephen D Green