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   Re: [xml-dev] Registered namespace prefixes

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james anderson wrote:

> overstates the inferences which are properly made based on namespace names. it is claimed that
> "On the contrary, what remains are nothing but scope issues. The intent of namespaces is to disambiguate names by properly assigning them to semantic domains, ..."
> this would be a mistake. the intent of namespaces is to disambiquate qualified names by properly assigning them to collections of universal names. if you will,
> "symbolic domains".

I agree with that. But the purpose of such assignment in *processing XML* is to associate names with appropriate processing or, if you will, dispatch on the name
correctly understood within its proper taxonomy (which I believe was Elliotte's point).

> the mechanism used to bind a symbolic domain to a semantic domain is a matter for the processing infrastructure


> and not a matter for namespaces.

namespaces is the basis in taxonomy for completely understanding the name, so that it might correctly be associated with processing, from the execution of which
particular semantics are elaborated

> in lisp, depending on your processor, names are modelled as symbols, strings, or other interned instances. name data may be interned such that it has global identity
> or document-specific identity. unique to symbols is that you can bind processing functions directly to the names - both dynamically and statically. in all cases, the
> names can serve as specializers for generic functions, or as keys in hash tables or other dictionary forms and thereby associate a process with a name.

all of this is so; it stops just short of the purpose for which it is done, which is to execute the process associated with a name and thereby elaborate, from that
processing on that occasion of the contents associated in a document instance with the identified name, a particular semantic outcome

> none of this has to do with namespaces. it has exclusively to do with the semantics of the implementation language.

no, it has to do with the semantics elaborated on a particular occasion though the execution of a particular implementation of process against content associated with
the name correctly identified via a namespace scheme

> on the other hand, some aspects of versioning have very much to do with names, and therefore with namespaces, and deserve more attention than has yet been awarded
> them.


> it is important to treat them separately from any attempt to version sematic domains.

and I do, most strictly. A semantic domain is a body of outcomes of process. Assignment via namespaces is to process and only indirectly to the semantic outcomes of
that process. In my posting which you quote I distinguish "the intent of namespaces is to disambiguate names by properly assigning them to semantic domains" (which you
cite) from "but from the point of view of the processing nodes which will act upon the documents in which those names are found, the only accurate (or useful)
assignment of names to domains is the assignment to particular processing from among the choices which might be invoked at that node" (which you do not cite). I
believe that this is the equivalent of Elliotte's point "to be able to dispatch the element to the right handler without a lot of effort. namespaces enable this".

> in particular, it is imperative that specifications for namespaces permit one to declare synonyms, that is names from distinct namespaces which, at least, based on
> local-part equality, should be understood to denote the same universal name. with this, one can express versioning relationships succinctly. without it they are a
> nightmare.

**AMEN**. However synonymy in this case means that names indicate content which might usefully be handled by the same processing, in order to achieve congruent
semantic outcomes. I believe that identifying names with sufficient accuracy in order that we might declare then synonymous requires identifying them on the two axes
of provenance and structure. When names thus identified are associated with the same process, we thereby declare the synonymy that, in the outcome of that process,
those name will yield congruent semantics.


Walter Perry


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