Emanuele De Angelis Wim Vanhoof (Eds.) Logic-Based 0 9 Program Synthesis 2 3 1 S and Transformation C N L 31st International Symposium, LOPSTR 2021 Tallinn, Estonia, September 7–8, 2021 Proceedings Lecture Notes in Computer Science 13290 FoundingEditors GerhardGoos KarlsruheInstituteofTechnology,Karlsruhe,Germany JurisHartmanis CornellUniversity,Ithaca,NY,USA EditorialBoardMembers ElisaBertino PurdueUniversity,WestLafayette,IN,USA WenGao PekingUniversity,Beijing,China BernhardSteffen TUDortmundUniversity,Dortmund,Germany GerhardWoeginger RWTHAachen,Aachen,Germany MotiYung ColumbiaUniversity,NewYork,NY,USA Moreinformationaboutthisseriesathttps://link.springer.com/bookseries/558 · Emanuele De Angelis Wim Vanhoof (Eds.) Logic-Based Program Synthesis and Transformation 31st International Symposium, LOPSTR 2021 Tallinn, Estonia, September 7–8, 2021 Proceedings Editors EmanueleDeAngelis WimVanhoof IASI-CNR UniversityofNamur Rome,Italy Namur,Belgium ISSN 0302-9743 ISSN 1611-3349 (electronic) LectureNotesinComputerScience ISBN 978-3-030-98868-5 ISBN 978-3-030-98869-2 (eBook) https://doi.org/10.1007/978-3-030-98869-2 ©SpringerNatureSwitzerlandAG2022 Thisworkissubjecttocopyright.AllrightsarereservedbythePublisher,whetherthewholeorpartofthe material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storageandretrieval,electronicadaptation,computersoftware,orbysimilarordissimilarmethodologynow knownorhereafterdeveloped. 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ThisSpringerimprintispublishedbytheregisteredcompanySpringerNatureSwitzerlandAG Theregisteredcompanyaddressis:Gewerbestrasse11,6330Cham,Switzerland Preface This volume contains a selection of the papers presented at LOPSTR 2021, the 31st InternationalSymposiumonLogic-BasedProgramSynthesisandTransformationheld during September 7–8, 2021, as a hybrid (blended) meeting, both in-person (at the Teachers’HouseinTallinn,Estonia)andvirtually,andco-locatedwithPPDP2021,the 23rdInternationalSymposiumonPrinciplesandPracticeofDeclarativeProgramming. PreviousLOPSTRsymposiawereheldinBologna(2020asavirtualmeeting),Porto (2019), Frankfurt am Main (2018), Namur (2017), Edinburgh (2016), Siena (2015), Canterbury(2014),Madrid(2013and2002),Leuven(2012and1997),Odense(2011), Hagenberg (2010), Coimbra (2009), Valencia (2008), Lyngby (2007), Venice (2006 and 1999), London (2005 and 2000), Verona (2004), Uppsala (2003), Paphos (2001), Manchester (1998, 1992, and 1991), Stockholm (1996), Arnhem (1995), Pisa (1994), andLouvain-la-Neuve(1993).Moreinformationaboutthesymposiumcanbefoundat: http://saks.iasi.cnr.it/lopstr21/. TheaimoftheLOPSTRseriesistostimulateandpromoteinternationalresearchand collaborationonlogic-basedprogramdevelopment. LOPSTRisopentocontributions inlogic-basedprogramdevelopmentinanylanguageparadigm.Topicsofinterestcover all aspects of logic-based program development, all stages of the software life cycle, andissuesofbothprogramming-in-the-smallandprogramming-in-the-large,including synthesis;transformation;specialization;composition;optimisation;inversion;specifi- cation;analysisandverification;testingandcertification;programandmodelmanipu- lation;machinelearningforprogramdevelopment;verificationandtestingofmachine learningsystems;transformationaltechniquesinsoftwareengineering;andapplications andtools.LOPSTRhasareputationforbeingalively,friendlyforumforpresentingand discussingworkinprogress.Formalproceedingsareproducedafterthesymposiumso thatauthorscanincorporatethisfeedbackinthepublishedpapers. Inresponsetothecallforpapers,16contributionsweresubmittedfromauthorsin10 differentcountries.Oneofthesubmissionswaswithdrawnbytheauthors,andeachofthe remainingsubmissionswasreviewedbythreeProgramCommitteemembersorexternal referees. The Program Committee accepted one full paper for immediate inclusion in the formal proceedings; nine more submissions were selected for presentation at the symposium. In addition, the symposium program included the joint PPDP-LOPSTR invitedtalksbyHaraldSøndergaard(UniversityofMelbourne,Australia)andStephen Wolfram(WolframResearch,UK).Afterthesymposium,theauthorsofthecontributions accepted for presentation were invited to revise and extend their submissions. Then, after another round of reviewing, the Program Committee accepted seven more full papersforinclusionintheformalproceedings.Inadditiontotheeightacceptedpapers, thisvolumeincludesthepapercontributedbytheinvitedspeakerHaraldSøndergaard: “Stringabstractdomainsandtheircombination”. Thanks to Springer’s sponsorship, LOPSTR 2021 featured a best paper award. The Program Committee assigned the award to “Disjunctive Delimited Control” by AlexanderVandenbrouckeandTomSchrijvers. vi Preface WewanttothanktheProgramCommitteemembers,whoworkeddiligentlytopro- ducehigh-qualityreviewsforthesubmittedpapers,aswellasalltheexternalreviewers involved in the paper selection. We are very grateful to the Local Organization Com- mittee, chaired by Niccolò Veltri, for the great job they did in managing the hybrid in-personandvirtualevent.WearegratefultoEasyChairforprovidingsupporttodeal with the submission and reviewing process. Special thanks go to all the authors who submittedtheirpaperstoLOPSTR2021,withoutwhomthesymposiumwouldhavenot be possible. Emanuele De Angelis is member of the INdAM Research group GNCS. WimVanhoofisamemberoftheNamurDigitalInstitute(NADI). February2022 EmanueleDeAngelis WimVanhoof Organization ProgramChairs EmanueleDeAngelis InstituteforSystemsAnalysisandComputer Science“A.Ruberti”–NationalResearch Council,Italy WimVanhoof UniversityofNamur,Belgium ProgramCommittee RobertoAmadini UniversityofBologna,Italy SabineBroda UniversityofPorto,Portugal MaximilianoCristiá CIFASIS-UNR,Argentina WłodzimierzDrabent IPIPAN,Poland,andLinköpingUniversity, Sweden CatherineDubois Samovar,ENSIIE,France GregoryDuck NationalUniversityofSingapore,Singapore FabioFioravanti UniversityofChieti-Pescara,Italy JeremyGibbons UniversityofOxford,UK GopalGupta UniversityofTexasatDallas,USA GeoffHamilton DublinCityUniversity,Ireland MichaelHanus KielUniversity,Germany BishoksanKafle IMDEASoftwareInstitute,Spain MajaKirkeby RoskildeUniversity,Denmark TemurKutsia RISC,JohannesKeplerUniversityofLinz, Austria MichaelLeuschel UniversityofDüsseldorf,Germany PedroLópez-García IMDEASoftwareInstituteandSpanishNational ResearchCouncil,Spain JacopoMauro UniversityofSouthernDenmark,Denmark FredMesnard UniversitédelaRéunion,France AlbertoMomigliano UniversityofMilan,Italy JorgeA.Navas SRIInternational,USA NaokiNishida NagoyaUniversity,Japan AliciaVillanueva UniversitatPolitècnicadeValència,Spain viii Organization LocalOrganizingCommittee NiccolòVeltri(GeneralChair) TallinnUniversityofTechnology,Estonia RuthLaos TallinnUniversityofTechnology,Estonia KristelToom TallinnUniversityofTechnology,Estonia TarmoUustalu ReykjavikUniversity,IcelandandTallinn UniversityofTechnology,Estonia AdditionalReviewer NelmaMoreira Contents StringAbstractDomainsandTheirCombination ........................... 1 HaraldSøndergaard DataTypeInferenceforLogicProgramming .............................. 16 JoãoBarbosa,MárioFlorido,andVítorSantosCosta Automating the Functional Correspondence Between Higher-Order EvaluatorsandAbstractMachines ....................................... 38 MaciejBuszkaandDariuszBiernacki S-Semantics–anExample ............................................... 60 WłodzimierzDrabent DisjunctiveDelimitedControl ........................................... 75 AlexanderVandenbrouckeandTomSchrijvers TowardsSubstructuralProperty-BasedTesting ............................. 92 MarcoMantovaniandAlbertoMomigliano TheNext700ProgramTransformers ..................................... 113 GeoffHamilton RepresentationandProcessingofInstantaneousandDurativeTemporal Phenomena ........................................................... 135 ManolisPitsikalis,AlexeiLisitsa,andShanLuo Prefix-BasedTracinginMessage-PassingConcurrency ..................... 157 JuanJoséGonzález-AbrilandGermánVidal AuthorIndex ......................................................... 177