Copyful Streaming String Transducers
Copyless streaming string transducers (copyless SST) have been introduced by R. Alur and P. Černý in 2010 as a one-way deterministic automata model to define transductions of finite strings. Copyless SST extend deterministic finite state automata with a set of variables in which to store intermediate output strings, and those variables can be combined and updated all along the run, in a linear manner, i.e., no variable content can be copied on transitions. It is known that copyless SST capture exactly the class of MSO-definable string-to-string transductions, and are as expressive as deterministic two-way transducers. They enjoy good algorithmic properties. Most notably, they have decidable equivalence problem (in PSpace).
HDT0L systems and total deterministic copyful SST have the same expressive power,
the equivalence problem for deterministic copyful SST and the equivalence problem for HDT0L systems are inter-reducible, in linear time. As a consequence, equivalence of deterministic SST is decidable,
the functionality of non-deterministic copyful SST is decidable,
determining whether a deterministic copyful SST can be transformed into an equivalent deterministic copyless SST is decidable in polynomial time.
- 1.Alur, A., Černý, P.: Streaming transducers for algorithmic verification of single-pass list-processing programs. In: POPL, pp. 599–610 (2011)Google Scholar
- 2.Alur, R., Černý, P.: Expressiveness of streaming string transducers. In: FSTTCS, vol. 8, pp. 1–12 (2010)Google Scholar
- 3.Alur, R., D’Antoni, L.: Streaming tree transducers. CoRR, abs/1104.2599 (2011)Google Scholar
- 5.Alur, R., D’Antoni, L., Deshmukh, J.V., Raghothaman, M., Yuan, Y.: Regular functions and cost register automata. In: 28th Annual ACM/IEEE Symposium on Logic in Computer Science, LICS 2013, pp. 13–22. IEEE Computer Society (2013)Google Scholar
- 7.Alur, R., Filiot, E., Trivedi, A.: Regular transformations of infinite strings. In: LICS, pp. 65–74. IEEE (2012)Google Scholar
- 8.Benedikt, M., Duff, T., Sharad, A., Worrell, J.: Polynomial automata: zeroness and applications. In: Proceedings of the 32nd Annual ACM/IEEE Symposium on Logic in Computer Science, LICS 2017. ACM (2017, to appear)Google Scholar
- 10.Dartois, L., Filiot, E., Reynier, P.-A., Talbot, J.-M.: Two-way visibly pushdown automata and transducers. In: Proceedings of the 31st Annual ACM/IEEE Symposium on Logic in Computer Science, LICS 2016, pp. 217–226. ACM (2016)Google Scholar
- 15.Filiot, E., Krishna, S.N., Trivedi, A.: First-order definable string transformations. In: 34th International Conference on Foundation of Software Technology and Theoretical Computer Science, FSTTCS 2014. LIPIcs, vol. 29, pp. 147–159. Schloss Dagstuhl - Leibniz-Zentrum fuer Informatik (2014)Google Scholar
- 16.Filiot, E., Reynier, P.-A.: Transducers, logic and algebra for functions of finite words. SIGLOG News 3(3), 4–19 (2016)Google Scholar
- 21.Seidl, H., Maneth, S., Kemper, G.: Equivalence of deterministic top-down tree-to-string transducers is decidable. In: IEEE 56th Annual Symposium on Foundations of Computer Science, FOCS 2015, pp. 943–962. IEEE Computer Society (2015)Google Scholar