Fxt - A Transformation Tool for XML Documents

XML document processing is a subarea of tree processing for which the functional programming style is very natural. A pattern matcher is necessary for identifying parts of the tree to be processed. The functional style implies a processing model in which navigation is possible only to subtrees of a tree. This restriction can be compensated by using a tree pattern matcher able to relate to ancestors as well as to siblings of a match. On top of the powerful fxgrep XML pattern matcher, we build fxt, a transformation tool for XML documents. The functional processing model that fxt uses, allows an implementation much more efficient than implementations permitted by the processing model of the popular XSLT, where navigation in the input tree can proceed in arbitrary directions. The fxt transformations are specified in an intuitive, declarative way. Flexibility is provided by hooks to the full functionality of the SML programming language, as well as by the fxt's variable mechanism.