We study relations on trees defined by first-order constraints over a vocabulary that includes the tree extension relation Ì Ì ¼, holding if and only if every branch of Ì ex...
Abstract. We present an extension to linear-time temporal logic (LTL) that combines the temporal specification with the collection of statistical data. By collecting statistics ove...
Abstract. Tree-walking automata (TWAs) recently received new attention in the fields of formal languages and databases. Towards a better understanding of their expressiveness, we c...
We consider the navigational core of XPath, extended with two operators: the Kleene star for taking the transitive closure of path expressions, and a subtree relativisation operat...
Although monadic second-order logic (MSO) has been a foundation of XML queries, little work has attempted to take MSO formulae themselves as a programming construct. Indeed, MSO f...