Re: [xsl] I wrote an XSLT program that converts a mapping XML file into a large, powerful XSLT program

["Lizzi, Vincent vincent.lizzi@xxxxxxxxxxxxxxxxxxxx" <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx>]

Hi Roger,

This sounds like really useful generalized solution! It also shows benefits of
doing up analysis and tooling work up front. Thank you for sharing!

Does the mapping file have a way to express things that might be context or
content dependent, such as variations in how a particular element may have
been used (or misused) in different ways?

Best regards,
Vincent

_____________________________________________
Vincent M. Lizzi
Head of Information Standards | Taylor & Francis Group
vincent.lizzi@xxxxxxxxxxxxxxxxxxxx<mailto:vincent.lizzi@xxxxxxxxxxxxxxxxxxxx>



Information Classification: General
From: Piez, Wendell A. (Fed) wendell.piez@xxxxxxxx
<xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx>
Sent: Wednesday, October 30, 2024 11:55 AM
To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
Subject: Re: [xsl] I wrote an XSLT program that converts a mapping XML file
into a large, powerful XSLT program

Hey Roger --

You are so right about XSLT as a transpiler and support framework for DSLs.

All the files in an OSCAL release, such as
https://github.com/usnistgov/OSCAL/releases/tag/v1.1.2<https://github.com/usn
istgov/OSCAL/releases/tag/v1.1.2>, are produced using XSLT. (Currently. That
may change!) This includes XSDs, JSON Schemas, and XSLTs. Look at
src/metaschema in that repository if you wish to see the transformation
sources.

Regards, Wendell

-----Original Message-----
From: Roger L Costello costello@xxxxxxxxx<mailto:costello@xxxxxxxxx>
<xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx<mailto:xsl-list-service@xxxxxxxxxxxx
rytech.com>>
Sent: Wednesday, October 30, 2024 7:46 AM
To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx<mailto:xsl-list@xxxxxxxxxxxxxxxxxxxxxx>
Subject: [xsl] I wrote an XSLT program that converts a mapping XML file into a
large, powerful XSLT program

Hi Folks,

I created an XML file (a "mapping file") that describes how to convert a
legacy XML format into a new XML format.

To implement the conversion, I used a pipeline approach. The first step is an
XSLT program that converts the mappings (in the mapping file) into a bunch of
template rules, one template rule per mapping. In other words, the output of
the first XSLT program is another XSLT program. (Cool! Dynamically generated
XSLT program) The second step ran the generated XSLT program on a legacy XML
file to produce XML in the new format.

Here are some statistics on file sizes:

Size of the mapping file: 383 KB
Size of the XSLT program that converts the mappings (in the mapping file) to
template rules: 154 KB Size of the XSLT program that was generated: 204622 KB
<-- Huge!

Lesson Learned: With a good description document (e.g., a good mappings
document) and a few lines of XSLT code, you can dynamically generate a huge
XSLT program that can do an enormous amount of work.

I love this approach to programming. It harkens back to my time writing
parsers and compilers.

/Roger