Andreas Abel, Jesper Cockx, Dominique Devriese, Amin Timany, Philip Wadler
{"title":"Leibniz equality is isomorphic to Martin-Löf identity, parametrically","authors":"Andreas Abel, Jesper Cockx, Dominique Devriese, Amin Timany, Philip Wadler","doi":"10.1017/S0956796820000155","DOIUrl":"https://doi.org/10.1017/S0956796820000155","url":null,"abstract":"Abstract Consider two widely used definitions of equality. That of Leibniz: one value equals another if any predicate that holds of the first holds of the second. And that of Martin-Löf: the type identifying one value with another is occupied if the two values are identical. The former dates back several centuries, while the latter is widely used in proof systems such as Agda and Coq. Here we show that the two definitions are isomorphic: we can convert any proof of Leibniz equality to one of Martin-Löf identity and vice versa, and each conversion followed by the other is the identity. One direction of the isomorphism depends crucially on values of the type corresponding to Leibniz equality satisfying functional extensionality and Reynolds’ notion of parametricity. The existence of the conversions is widely known (meaning that if one can prove one equality then one can prove the other), but that the two conversions form an isomorphism (internally) in the presence of parametricity and functional extensionality is, we believe, new. Our result is a special case of a more general relation that holds between inductive families and their Church encodings. Our proofs are given inside type theory, rather than meta-theoretically. Our paper is a literate Agda script.","PeriodicalId":15874,"journal":{"name":"Journal of Functional Programming","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2020-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1017/S0956796820000155","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48720155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Karachalias, Matija Pretnar, Amr Hany Saleh, Stien Vanderhallen, T. Schrijvers
{"title":"Explicit effect subtyping","authors":"G. Karachalias, Matija Pretnar, Amr Hany Saleh, Stien Vanderhallen, T. Schrijvers","doi":"10.1017/S0956796820000131","DOIUrl":"https://doi.org/10.1017/S0956796820000131","url":null,"abstract":"Abstract As popularity of algebraic effects and handlers increases, so does a demand for their efficient execution. Eff, an ML-like language with native support for handlers, has a subtyping-based effect system on which an effect-aware optimising compiler could be built. Unfortunately, in our experience, implementing optimisations for Eff is overly error-prone because its core language is implicitly typed, making code transformations very fragile. To remedy this, we present an explicitly typed polymorphic core calculus for algebraic effect handlers with a subtyping-based type-and-effect system. It reifies appeals to subtyping in explicit casts with coercions that witness the subtyping proof, quickly exposing typing bugs in program transformations. Our typing-directed elaboration comes with a constraint-based inference algorithm that turns an implicitly typed Eff-like language into our calculus. Moreover, all coercions and effect information can be erased in a straightforward way, demonstrating that coercions have no computational content. Additionally, we present a monadic translation from our calculus into a pure language without algebraic effects or handlers, using the effect information to introduce monadic constructs only where necessary.","PeriodicalId":15874,"journal":{"name":"Journal of Functional Programming","volume":"149 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2020-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77474946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Beniamino Accattoli, Stéphane Graham-Lengrand, D. Kesner
{"title":"Tight typings and split bounds, fully developed","authors":"Beniamino Accattoli, Stéphane Graham-Lengrand, D. Kesner","doi":"10.1017/s095679682000012x","DOIUrl":"https://doi.org/10.1017/s095679682000012x","url":null,"abstract":"Abstract Multi types – aka non-idempotent intersection types – have been used. to obtain quantitative bounds on higher-order programs, as pioneered by de Carvalho. Notably, they bound at the same time the number of evaluation steps and the size of the result. Recent results show that the number of steps can be taken as a reasonable time complexity measure. At the same time, however, these results suggest that multi types provide quite lax complexity bounds, because the size of the result can be exponentially bigger than the number of steps. Starting from this observation, we refine and generalise a technique introduced by Bernadet and Graham-Lengrand to provide exact bounds. Our typing judgements carry counters, one measuring evaluation lengths and the other measuring result sizes. In order to emphasise the modularity of the approach, we provide exact bounds for four evaluation strategies, both in the λ-calculus (head, leftmost-outermost, and maximal evaluation) and in the linear substitution calculus (linear head evaluation). Our work aims at both capturing the results in the literature and extending them with new outcomes. Concerning the literature, it unifies de Carvalho and Bernadet & Graham-Lengrand via a uniform technique and a complexity-based perspective. The two main novelties are exact split bounds for the leftmost strategy – the only known strategy that evaluates terms to full normal forms and provides a reasonable complexity measure – and the observation that the computing device hidden behind multi types is the notion of substitution at a distance, as implemented by the linear substitution calculus.","PeriodicalId":15874,"journal":{"name":"Journal of Functional Programming","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2020-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1017/s095679682000012x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46164300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Begehren als queeres Phänomen","authors":"Eleonora Ciani, Marcus Fassl","doi":"10.30820/0942-2285-2020-1-46","DOIUrl":"https://doi.org/10.30820/0942-2285-2020-1-46","url":null,"abstract":"Begehren zu definieren ist generell ein schwieriges Unterfangen, da es konzeptuell durch multiple und reichhaltige sowie durchaus widerspruchliche Nuancen gepragt ist. Die Queer Theory hat viele der wesentlichen Annahmen, welche die Kontinuitat zwischen Geschlecht, Gender, sexueller Praxis und Begehren erst ermoglichen, unter anderem als diskursiv-linguistische Konstrukte entlarvt. Allerdings fehlt die Erforschung der materiellen Dimensionen von Begehren. Dieser Artikel schildert eine autoethnografische Reise durch Szenarien von Begehren und stellt personliche Erfahrungen in Verbindung mit verschiedenen theoretischen Ansatzen, die den Autor_innen im Laufe der Recherche begegnet sind. Insbesondere eine queer-feministische Lesart Neuer Materialismen kann Sichtweisen auf Begehren erweitern und wertvolle Erkenntnisse daruber liefern, wie und wo Begehren auftreten konnte.","PeriodicalId":15874,"journal":{"name":"Journal of Functional Programming","volume":"28 1","pages":"46-66"},"PeriodicalIF":1.1,"publicationDate":"2020-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48635543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Art-based Public Sociology","authors":"R. Jende","doi":"10.30820/0942-2285-2020-1-86","DOIUrl":"https://doi.org/10.30820/0942-2285-2020-1-86","url":null,"abstract":"This article reflects upon the experience of a two-semesters research project at the Department of Sociology at the Friedrich Schiller University in Jena. It deals with a participant observation of the first international real-time architecture festival »72 Hour Urban Action«, which took place from 2 to 5 May 2019 in the middle of the large housing estate Lobeda West in the periphery of Jena. The mission of the architectural intervention was to create ten new meeting places and to encourage the neighbourhood’s residents to participate in the design of public spaces. As field researchers, we worked closely with urban planners, cultural and creative artists and by doing so became part of the research object. We developed artistic forms of presentation and provided relevant knowledge about the district throughout the process of realizing the architecture festival. The aim of this article is to shine a light upon the potential of participatory urban space development and the role of performative social science in the process.","PeriodicalId":15874,"journal":{"name":"Journal of Functional Programming","volume":"28 1","pages":"86-107"},"PeriodicalIF":1.1,"publicationDate":"2020-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46487506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Der sozialwissenschaftliche Film","authors":"Katharina Miko-Schefzig","doi":"10.30820/0942-2285-2020-1-134","DOIUrl":"https://doi.org/10.30820/0942-2285-2020-1-134","url":null,"abstract":"Seit dem sogenannten Visual Turn wird auch dem Einsatz von Film in den Sozialwissenschaften mehr Aufmerksamkeit geschenkt. Dabei ist die Nutzung zweigeteilt: einerseits als Erhebungs- und Auswertungsmethode, andererseits als wissenschaftlicher Output. In diesem Artikel werden die Herausforderungen und Potenziale der Produktion sozialwissenschaftlicher Filme diskutiert. Es wird sowohl auf methodologische und theoretische Fragen wie auf Fragen der konkreten Umsetzung eingegangen. Zentrale Schritte im Forschungsprozess werden in ihrer Bedeutung fur die Filmarbeit diskutiert. Umgekehrt werden deren spezifische Stilmittel, etwa der Schnitt, in ihrer Bedeutung fur die empirische Arbeit dargestellt. Schlussendlich werden die Folgen eines vermehrten Einsatzes von Film fur das Wissenschaftssystem, etwa fur die Publikationsmoglichkeiten, beleuchtet.","PeriodicalId":15874,"journal":{"name":"Journal of Functional Programming","volume":"28 1","pages":"134-155"},"PeriodicalIF":1.1,"publicationDate":"2020-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46745117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Performative Sozialwissenschaft – im Gespräch","authors":"G. Mey","doi":"10.30820/0942-2285-2020-1-3","DOIUrl":"https://doi.org/10.30820/0942-2285-2020-1-3","url":null,"abstract":"Im Editorial werden Annotationen zur Entstehung des Themenheftes \"Performative Sozialwissenschaft\" vorgenommen. Eingebettet darin finden sich Ausfuhrungen zum Anliegen und zu den Anspruchen, Forschung mit kunstlerisch-asthetischen Mitteln zu betreiben und umzusetzen -- wobei auch kenntlich gemacht wird, dass in der performativ-sozialwissenschaftlichen Praxis ganz verschiedene Realisierungsformate exisitieren.","PeriodicalId":15874,"journal":{"name":"Journal of Functional Programming","volume":"28 1","pages":"3-14"},"PeriodicalIF":1.1,"publicationDate":"2020-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45522387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Local algebraic effect theories","authors":"Žiga Lukšič, Matija Pretnar","doi":"10.1017/S0956796819000212","DOIUrl":"https://doi.org/10.1017/S0956796819000212","url":null,"abstract":"Abstract Algebraic effects are computational effects that can be described with a set of basic operations and equations between them. As many interesting effect handlers do not respect these equations, most approaches assume a trivial theory, sacrificing both reasoning power and safety. We present an alternative approach where the type system tracks equations that are observed in subparts of the program, yielding a sound and flexible logic, and paving a way for practical optimisations and reasoning tools.","PeriodicalId":15874,"journal":{"name":"Journal of Functional Programming","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2020-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1017/S0956796819000212","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49203506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Fault-tolerant functional reactive programming (extended version)","authors":"Ivan Perez, Alwyn E. Goodloe","doi":"10.1017/S0956796820000118","DOIUrl":"https://doi.org/10.1017/S0956796820000118","url":null,"abstract":"Abstract Highly critical application domains, like medicine and aerospace, require the use of strict design, implementation, and validation techniques. Functional languages have been used in these domains to develop synchronous dataflow programming languages for reactive systems. Causal stream functions and functional reactive programming (FRP) capture the essence of those languages in a way that is both elegant and robust. To guarantee that critical systems can operate under high stress over long periods of time, these applications require clear specifications of possible faults and hazards, and how they are being handled. Modeling failure is straightforward in functional languages, and many functional reactive abstractions incorporate support for failure or termination. However, handling unknown types of faults, and incorporating fault tolerance into FRP, requires a different construction and remains an open problem. This work demonstrates how to extend an existing functional reactive framework with fault tolerance features. At value level, we tag faulty signals with reliability and probability information and use random testing to inject faults and validate system properties encoded in temporal logic. At type level, we tag components with the kinds of faults they may exhibit and use type-level programming to obtain compile-time guarantees of key aspects of fault tolerance. Our approach is powerful enough to be used in systems with realistic complexity, and flexible enough to be used to guide system analysis and design, validate system properties in the presence of faults, perform runtime monitoring, and study the effects of different fault tolerance mechanisms.","PeriodicalId":15874,"journal":{"name":"Journal of Functional Programming","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2020-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1017/S0956796820000118","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43658522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Klassenmanagement bei angehenden Lehrkräften aufbauen","authors":"M. Gehrmann","doi":"10.30820/0942-2285-2019-2-95","DOIUrl":"https://doi.org/10.30820/0942-2285-2019-2-95","url":null,"abstract":"Efficient classroom management is a necessary condition of high-quality, inclusive teaching. Thus, the development of essential competences is a desideratum in teacher education. A seminar concept based on video-assisted micro-teaching for students in their practical semester is presented and evaluated. Derived from the model of professional competence of teachers, we examine how job-related and self-efficacy beliefs regarding inclusive education can foster the development and application of classroom management strategies. Two intervention-phases with a total of 35 students in the treatment and 34 students in the control group were carried out. Obtained data point in the expected direction but only show medium effects for performance in behavior management. Beliefs concerning inclusive education remained relatively stable among all students. Moreover, self-efficacy for inclusive teaching practices increased at the end of the practical semester. The influence on intervention effects does not seem clear.","PeriodicalId":15874,"journal":{"name":"Journal of Functional Programming","volume":"27 1","pages":"95-116"},"PeriodicalIF":1.1,"publicationDate":"2020-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43060244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号
