Logics for Unranked Trees: An Overview [chapter]

Leonid Libkin
2005 Lecture Notes in Computer Science  
Labeled unranked trees are used as a model of XML documents, and logical languages for them have been studied actively over the past several years. Such logics have different purposes: some are better suited for extracting data, some for expressing navigational properties, and some make it easy to relate complex properties of trees to the existence of tree automata for those properties. Furthermore, logics differ significantly in their model-checking properties, their automata models, and their
more » ... behavior on ordered and unordered trees. In this paper we present a survey of logics for unranked trees.
doi:10.1007/11523468_4 fatcat:7rcqqszwefaurpnvx4pkvbqusq