A Missing Link in Root-to-Frontier Tree Pattern Mat hing
نویسندگان
چکیده
Abstra t. Tree pattern mat hing (tpm) algorithms play an important role in pra ti al appli ations su h as ompilers and XML do ument validation. Many tpm algorithms based on tree automata have appeared in the literature. For reasons of eÆ ien y, these automata are preferably deterministi . Deterministi root-to-frontier tree automata (drftas) are less powerful than nondeterministi ones, and no root-to-frontier tpm algorithm using drftas has appeared so far. Ho mann & O'Donnell [HO82℄ presented a root-to-frontier tpm algorithm based on an Aho-Corasi k automaton re ognizing tree stringpaths, but no relationship between this algorithm and algorithms using tree automata has been des ribed. In this paper, we show that a spe i drfta an be used for stringpath mat hing in a root-to-frontier tpm algorithm. This algorithm has not appeared in the literature before, and provides a missing link between tpm algorithms using stringpath automata and those using tree automata.
منابع مشابه
A missing link in root-to-frontier tree pattern matching
Tree pattern matching (tpm) algorithms play an important role in practical applications such as compilers and XML document validation. Many tpm algorithms based on tree automata have appeared in the literature. For reasons of efficiency, these automata are preferably deterministic. Deterministic root-to-frontier tree automata (drftas) are less powerful than nondeterministic ones, and no root-to...
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