Conditional XPath, the first order complete XPath dialect

• DOI: 10.1145/1055558.1055562
• Publication Date: 2005-08-03T04:31:47Z
• Authors: Maarten Marx
• Keywords: XPath; Path expression; XSLT

XPath is the W3C -- standard node addressing language for XML documents. still under development and its technical aspects are intensively studied. What missing at present a clear characterization of expressive power XPath, be it either semantical or with reference to some well established existing (logical) formalism. Core (the logical core 1.0 defined by Gottlob et al.) cannot express queries conditional paths as exemplified "do child step, while test true resulting node." In first-order complete extension such expressible, We add axis relations show that language, called equally logic when interpreted on ordered trees. Both result, extended proof closely related temporal logic. Specifically, may viewed simple logic, extends this (counterparts of) since until operators.