Transformation-by-Example for XML

Shriram Krishnamurthi, Kathryn E. Gray and Paul T. Graunke

Practical Aspects of Declarative Languages, 2000

XML is a language for describing markup languages for structured data.
A growing number of applications that process XML documents are
*transformers*, i.e., programs that convert documents between XML
languages.  Unfortunately, the current proposals for transformers are
complex general-purpose languages, which will be unappealing as the
XML user base broadens and thus decreases in technical sophistication.
We have designed and implemented XT3D, a highly declarative XML
specification language.  It demands little more from users than a
knowledge of the expected input and desired output.  We illustrate the
power of XT3D with several examples, including one reminiscent of
polytypic programming that greatly simplifies the import of XML values
into general-purpose languages.