Re: [xml-dev] RE: Data Interoperability ... Why do some XML vocabularie

[David Carlisle <davidc@nag.co.uk>]

On 20/08/2010 17:53, Costello, Roger L. wrote:
> Consider XSLT. I can create an XSLT document and run it on my XSLT
> processor. I can send the XSLT document to you and you run it on your
> XSLT processor. We get the same behavior. We agree perfectly on what
> the<xsl:for-each>  element means and how it should behave. Ditto for
> all the other elements and attributes in the XSLT vocabulary.
>
> We have successfully interoperated.

This is all true but nothing to do with XML, the same could be said of a 
Fortran program, which you might compile with a different fortran 
compiler to me.
>
> What enabled this?
>
> What enabled the interoperability is the fact that we are using the
> same Prime App.
That's a particularly unfortunate terminology, most people would 
consider different XSLT implementations to be different applications.

(You may be using Xalan and I may be using Saxon;
> they both belong to the same class of Prime Apps.

But as I say above all the above is true of any defined language. What 
distinguishes XML is that the syntax is standardised separately to any 
application behaviour, so while it's quite hard to process a Fortran 
file (or c or java ...) without a specific language compiler, an XSLT 
file is XML which means that it can be used in other contexts without 
using an XSLT application, most notably it is easy to use XSLT as the 
source for a different transformation because it is XML which enables it 
to be used as data rather than being executed.

So it seems to me that the benefits a language gets by using an XML 
syntax are primarily that it's use is not tied to any particular 
application type.

David