Some of the most relevant document schemas used online, such as XML and JSON, have a nested format. In last decade, task extracting data from documents over streams has become especially relevant. We focus on streaming evaluation queries with outputs varied sizes documents. model this kind Visibly Pushdown Annotators (VPAnn), computational that extends visibly pushdown automata same expressive power MSO Since processing through VPAnn can generate massive number results, we are interested in...

We introduce annotated grammars, an extension of context-free grammars which allows annotations on terminals. Our model extends the standard notion regular spanners, and is more expressive than extraction recently introduced by Peterfreund. study enumeration problem for grammars: fixing a grammar, given string as input, enumerate all that form word derivable from grammar. first result algorithm unambiguous preprocesses input in cubic time enumerates with output-linear delay. This improves...

Descriptive Complexity has been very successful in characterizing complexity classes of decision problems terms the properties definable some logics. However, descriptive for counting classes, such as FP and #P, not systematically studied, it is developed its counterpart. In this paper, we propose a framework based on Weighted Logics to address issue. Specifically, by focusing natural numbers obtain logic called Quantitative Second Order (QSO), show how fragments can be used capture...

Descriptive Complexity has been very successful in characterizing complexity classes of decision problems terms the properties definable some logics. However, descriptive for counting classes, such as FP and #P, not systematically studied, it is developed its counterpart. In this paper, we propose a framework based on Weighted Logics to address issue. Specifically, by focusing natural numbers obtain logic called Quantitative Second Order (QSO), show how fragments can be used capture...

Descriptive Complexity has been very successful in characterizing complexity classes of decision problems terms the properties definable some logics. However, descriptive for counting classes, such as FP and #P, not systematically studied, it is developed its counterpart. In this paper, we propose a framework based on Weighted Logics to address issue. Specifically, by focusing natural numbers obtain logic called Quantitative Second Order (QSO), show how fragments can be used capture...

Descriptive Complexity has been very successful in characterizing complexity classes of decision problems terms the properties definable some logics. However, descriptive for counting classes, such as FP and #P, not systematically studied, it is developed its counterpart. In this paper, we propose a framework based on Weighted Logics to address issue. Specifically, by focusing natural numbers obtain logic called Quantitative Second Order (QSO), show how fragments can be used capture...