A transformation language is a computer language designed to transform some input text in a certain formal language into a modified output text that meets some specific goal[clarification needed].
The transformation languages for these systems are driven by declarative descriptions of the structure of the input text (typically a grammar), allowing them to be applied to wide variety of formal languages and documents.
There are also low-level languages such as the Lx family[1] implemented by the bootstrapping method.
There is also a high-level graphical language built on upon Lx called MOLA.
These include Tritium, XSLT, XQuery, STX, FXT, XDuce, CDuce, HaXml, XMLambda, and FleXML.