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Operations on recognizers

Since predicate-augmented finite state recognizers are equivalent to ordinary finite-state automata, the class of languages defined by psfr is closed under the the usual regular operations such as union, concatenation, Kleene-closure and reversal. From a practical point of view, however, it is interesting to note that it is trivial to generalize the corresponding constructions for classical finite state automata (cf. for instance [13]). This means that the various constructions can be implemented directly, without the need to expand into ordinary finite automata first, which is impractical for large alphabets.


Noord G.J.M. van