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Regular expressions and the equivalence of programs

Donald M. Kaplan
1969 Journal of computer and system sciences (Print)  
If we assume that the study and detection of equivalence for ALGOL-like programs holds certain pragmatic interest, then it seems reasonable to pursue these matters despite the well-known undecidability  ...  These procedures always produce an answer when questioned as to the equivalence of two programs: either YES or MAYBE.  ...  Manna for his critical reading of the manuscript and subsequent helpful suggestions.  ... 
doi:10.1016/s0022-0000(69)80027-9 fatcat:7jjoinkpxvefdanbsfan4m57vi

SemRegex: A Semantics-Based Approach for Generating Regular Expressions from Natural Language Specifications

Zexuan Zhong, Jiaqi Guo, Wei Yang, Jian Peng, Tao Xie, Jian-Guang Lou, Ting Liu, Dongmei Zhang
2018 Proceedings of the 2018 Conference on Empirical Methods in Natural Language Processing  
SemRegex provides solutions for a subtask of the program-synthesis problem: generating regular expressions from natural language.  ...  Different from the existing syntax-based approaches, SemRegex trains the model by maximizing the expected semantic correctness of the generated regular expressions.  ...  CNS-1513939, CNS-1564274, and CCF-1816615. The work from the authors at Xi'an Jiaotong University was supported by National Natural Science Foundation of China (61632015, 61772408, 61721002).  ... 
doi:10.18653/v1/d18-1189 dblp:conf/emnlp/ZhongGYPXLLZ18 fatcat:vansoeidmnbvbpl6do5ibmygne

Observations on the complexity of regular expression problems

H.B. Hunt
1979 Journal of computer and system sciences (Print)  
Several observations are presented on the computational complexity of regular expression problems.  ...  The complexity of the equivalence and containment problems is shown to be "essentially" independent of the structure of the languages represented.  ...  As Kaplan observed, (1) R-equivalence implies strong equivalence, and (2) the R-equivalence problem for program schemes is effectively reducible to the regular expression equivalence problem.  ... 
doi:10.1016/0022-0000(79)90002-3 fatcat:fmynjz4tk5du3oicfvf4tk3p6q

The WHILE hierarchy of program schemes is infinite [chapter]

Can Adam Albayrak, Thomas Noll
1998 Lecture Notes in Computer Science  
We exhibit a sequence Sn (n ≥ 0) of while program schemes, i. e., while programs without interpretation, with the property that the while nesting depth of Sn is n, and prove that any while program scheme  ...  Our proof is based on results from formal language theory; in particular, we make use of the notion of star height of regular languages.  ...  Acknowledgements: We would like to thank Klaus Indermark for the premise of this work, as well as Markus Mohnen and Thomas Wilke for the effort of reading a draft version of this paper.  ... 
doi:10.1007/bfb0053540 fatcat:5tgbb7cx7bcx3ak5e4n5roiaza

Deciding Kleene algebra terms equivalence in Coq

Nelma Moreira, David Pereira, Simão Melo de Sousa
2015 Journal of Logical and Algebraic Methods in Programming  
The algorithm decides equivalence of two given regular expressions through an iterated process of testing the equivalence of their partial derivatives and does not require the construction of the corresponding  ...  The algorithm decides equivalence of two given regular expressions through an iterated process of testing the equivalence of their partial derivatives and does not require the construction of the corresponding  ...  Programme 'Thematic Factors of Competitiveness'), within projects PTDC/EIA/65862/2006 (RESCUE), PTDC/EIA-CCO/101904/2008 (CANTE), FCOMP-01-0124-FEDER-020486 (AVIACC), and FCOMP-01-0124-FEDER-037281 (CISTER  ... 
doi:10.1016/j.jlamp.2014.12.004 fatcat:5mshu6hn6bcrho67ye7hk2ax5m

Extending Timbuk to Verify Functional Programs [chapter]

Thomas Genet, Tristan Gillard, Timothée Haudebourg, Sébastien Lê Cong
2018 Lecture Notes in Computer Science  
The first extension is a language, based on regular tree expressions, which eases the specification of the property to prove on the program.  ...  The second extension automatically generates a set of equations adapted to the property to prove on the program.  ...  Acknowledgements Many thanks to the anonymous referees for their valuable comments.  ... 
doi:10.1007/978-3-319-99840-4_9 fatcat:4suu76ksvfaxzoyzk5quung6ka

Synthesizing bijective lenses

Anders Miltner, Kathleen Fisher, Benjamin C. Pierce, David Walker, Steve Zdancewic
2017 Proceedings of the ACM on Programming Languages  
In particular, and unlike most prior work on type-directed synthesis, our system operates in the context of a language with a rich equivalence relation on types (the theory of regular expressions).  ...  The inputs to Optician are a pair of ordinary regular expressions representing two data formats and a few concrete examples for disambiguation.  ...  ACKNOWLEDGMENTS We thank our anonymous reviewers, Loris D'Antoni, Fritz Henglein, Neil Jones, and Nate Foster for their useful feedback and discussions.  ... 
doi:10.1145/3158089 dblp:journals/pacmpl/MiltnerFPWZ18 fatcat:e2t44uwnrrbrldgewtulwvlyre

Monadic logic programs and functional complexity

Armando B. Matos
1997 Theoretical Computer Science  
It is proved that the class of monadic programs corresponds exactly to the class of regular languages. As a consequence, the "SUCCESS" problem is decidable for that class.  ...  It is also proved that the success set of a specific subclass of monadic programs ("simple" programs) corresponds exactly to regular languages with star-height not exceeding 1.  ...  Acknowledgements We would like to express our gratitude to a referee of the first version of this paper for calling our attention on the work of Biichi [3] .  ... 
doi:10.1016/s0304-3975(96)00093-x fatcat:fi66bby6vfampm2y6j43b2l3le

A Modified Completeness Theorem of KAT and Decidability of Term Reducibility [chapter]

Takeo Uramoto
2014 Lecture Notes in Computer Science  
), keeping the equivalence of programs.  ...  the regular expression p as a regular language.  ... 
doi:10.1007/978-3-319-06251-8_6 fatcat:ktntbbvhy5dnlohbxo2s42jkfu

A 'division' transformation for program and data structures and the structure clash problem

Beat Michel
1988 Science of Computer Programming  
Thus, equivalence classes of regular expressions that are decompositions of each other may be defined.  ...  At the same time, it is mathematically treated in terms of regular algebra and is shown to be reflexive, symmetric and transitive.  ...  One of the referees suggested the use of regular algebra; Giovanni Coray (EPFL) gave me some advice on this subject.  ... 
doi:10.1016/0167-6423(88)90051-2 fatcat:oilygdid4rebnoed33uewgerfu

Definability in dynamic logic

Albert R. Meyer, Rohit Parikh
1981 Journal of computer and system sciences (Print)  
One version of Dynamic Logic is equivalent to the infinitary logic Lz:"" but regular Dynamic Logic is strictly less expressive.  ...  In particular, the ordinals ww and 0".2 are indistinguishable by formulas of regular Dynamic Logic.  ...  Tiuryn for several valuable discussions and Dexter Kozen who, spotted a serious lacuna in our original proof of Theorem 4.  ... 
doi:10.1016/0022-0000(81)90016-7 fatcat:xqf6cd7tqja7pjigizjidcko7e

Propositional dynamic logic is weaker without tests

Francine Berman, Michael Paterson
1981 Theoretical Computer Science  
whit h is not equivalent to any formula of PDL using only the re,gular program operators concatenation, branchkg and iteration. Extensi'ons of the problem are discussed in t.he conclusion.  ...  WB show that Test-free Propositional Dynamic Logic (PDL") is less expressive th,an Propositional Dynamic Logic, i.e. we show that there is a formula of PDL using the caarditional program operator ?  ...  Acknowledgment The authors wish to thank Mike Fischer for helpful discussions and his support in this project, and Albert Meyer and the referees of Theoretical Comput'er Science for valuable suggestions  ... 
doi:10.1016/0304-3975(81)90102-x fatcat:zsrf27qc4zhhllf7kot7wlfsqu

Page 474 of Mathematical Reviews Vol. , Issue 96a [page]

1996 Mathematical Reviews  
“In Section 7 we comment about the relationship between our axiomatisation and Salomaa’s classical axiomatisation of language equivalence for regular expressions.  ...  A calculus of equivalences of the abstract programs and techniques for solving equations within the limits of the calculus are presented.  ... 

Bounds on the propagation of selection into logic programs

Catriel Beeri, Paris Kanellakis, Francois Bancilhon, Raghu Ramakrishnan
1990 Journal of computer and system sciences (Print)  
We further clarify the analogy between chain programs and context-free languages from the point of view of program equivalence, first-order expressibility over finite structures, and selection propagation  ...  In particular, we study the class of chain programs and formalize selection propagation on such a logic program as: the task of finding an equivalent program containing only monadic derived predicates.  ...  Moshe Vardi pointed out an alternative proof of Theorem 3.3 part (I), which uses WSlS on IG.  ... 
doi:10.1016/0022-0000(90)90035-j fatcat:5mkro4bjhncxleun6zk5vtmrrm

Bounds on the propagation of selection into logic programs

C. Beeri, P. Kanellakis, F. Bancilhon, R. Ramakrishnan
1987 Proceedings of the sixth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems - PODS '87  
We further clarify the analogy between chain programs and context-free languages from the point of view of program equivalence, first-order expressibility over finite structures, and selection propagation  ...  In particular, we study the class of chain programs and formalize selection propagation on such a logic program as: the task of finding an equivalent program containing only monadic derived predicates.  ...  Moshe Vardi pointed out an alternative proof of Theorem 3.3 part (I), which uses WSlS on IG.  ... 
doi:10.1145/28659.28683 dblp:conf/pods/BeeriKBR87 fatcat:ln5lk6ot4zafvdklmjb5s7ooyi
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