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Documents authored by Aldrich, Jonathan


Document
Complete Volume
LIPIcs, Volume 313, ECOOP 2024, Complete Volume

Authors: Jonathan Aldrich and Guido Salvaneschi

Published in: LIPIcs, Volume 313, 38th European Conference on Object-Oriented Programming (ECOOP 2024)


Abstract
LIPIcs, Volume 313, ECOOP 2024, Complete Volume

Cite as

38th European Conference on Object-Oriented Programming (ECOOP 2024). Leibniz International Proceedings in Informatics (LIPIcs), Volume 313, pp. 1-1324, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2024)


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@Proceedings{aldrich_et_al:LIPIcs.ECOOP.2024,
  title =	{{LIPIcs, Volume 313, ECOOP 2024, Complete Volume}},
  booktitle =	{38th European Conference on Object-Oriented Programming (ECOOP 2024)},
  pages =	{1--1324},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-341-6},
  ISSN =	{1868-8969},
  year =	{2024},
  volume =	{313},
  editor =	{Aldrich, Jonathan and Salvaneschi, Guido},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ECOOP.2024},
  URN =		{urn:nbn:de:0030-drops-208481},
  doi =		{10.4230/LIPIcs.ECOOP.2024},
  annote =	{Keywords: LIPIcs, Volume 313, ECOOP 2024, Complete Volume}
}
Document
Front Matter
Front Matter, Table of Contents, Preface, Conference Organization

Authors: Jonathan Aldrich and Guido Salvaneschi

Published in: LIPIcs, Volume 313, 38th European Conference on Object-Oriented Programming (ECOOP 2024)


Abstract
Front Matter, Table of Contents, Preface, Conference Organization

Cite as

38th European Conference on Object-Oriented Programming (ECOOP 2024). Leibniz International Proceedings in Informatics (LIPIcs), Volume 313, pp. 0:i-0:xx, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2024)


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@InProceedings{aldrich_et_al:LIPIcs.ECOOP.2024.0,
  author =	{Aldrich, Jonathan and Salvaneschi, Guido},
  title =	{{Front Matter, Table of Contents, Preface, Conference Organization}},
  booktitle =	{38th European Conference on Object-Oriented Programming (ECOOP 2024)},
  pages =	{0:i--0:xx},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-341-6},
  ISSN =	{1868-8969},
  year =	{2024},
  volume =	{313},
  editor =	{Aldrich, Jonathan and Salvaneschi, Guido},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ECOOP.2024.0},
  URN =		{urn:nbn:de:0030-drops-208495},
  doi =		{10.4230/LIPIcs.ECOOP.2024.0},
  annote =	{Keywords: Front Matter, Table of Contents, Preface, Conference Organization}
}
Document
Gradual Program Analysis for Null Pointers

Authors: Sam Estep, Jenna Wise, Jonathan Aldrich, Éric Tanter, Johannes Bader, and Joshua Sunshine

Published in: LIPIcs, Volume 194, 35th European Conference on Object-Oriented Programming (ECOOP 2021)


Abstract
Static analysis tools typically address the problem of excessive false positives by requiring programmers to explicitly annotate their code. However, when faced with incomplete annotations, many analysis tools are either too conservative, yielding false positives, or too optimistic, resulting in unsound analysis results. In order to flexibly and soundly deal with partially-annotated programs, we propose to build upon and adapt the gradual typing approach to abstract-interpretation-based program analyses. Specifically, we focus on null-pointer analysis and demonstrate that a gradual null-pointer analysis hits a sweet spot, by gracefully applying static analysis where possible and relying on dynamic checks where necessary for soundness. In addition to formalizing a gradual null-pointer analysis for a core imperative language, we build a prototype using the Infer static analysis framework, and present preliminary evidence that the gradual null-pointer analysis reduces false positives compared to two existing null-pointer checkers for Infer. Further, we discuss ways in which the gradualization approach used to derive the gradual analysis from its static counterpart can be extended to support more domains. This work thus provides a basis for future analysis tools that can smoothly navigate the tradeoff between human effort and run-time overhead to reduce the number of reported false positives.

Cite as

Sam Estep, Jenna Wise, Jonathan Aldrich, Éric Tanter, Johannes Bader, and Joshua Sunshine. Gradual Program Analysis for Null Pointers. In 35th European Conference on Object-Oriented Programming (ECOOP 2021). Leibniz International Proceedings in Informatics (LIPIcs), Volume 194, pp. 3:1-3:25, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2021)


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@InProceedings{estep_et_al:LIPIcs.ECOOP.2021.3,
  author =	{Estep, Sam and Wise, Jenna and Aldrich, Jonathan and Tanter, \'{E}ric and Bader, Johannes and Sunshine, Joshua},
  title =	{{Gradual Program Analysis for Null Pointers}},
  booktitle =	{35th European Conference on Object-Oriented Programming (ECOOP 2021)},
  pages =	{3:1--3:25},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-190-0},
  ISSN =	{1868-8969},
  year =	{2021},
  volume =	{194},
  editor =	{M{\o}ller, Anders and Sridharan, Manu},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ECOOP.2021.3},
  URN =		{urn:nbn:de:0030-drops-140469},
  doi =		{10.4230/LIPIcs.ECOOP.2021.3},
  annote =	{Keywords: gradual typing, gradual verification, dataflow analysis}
}
Document
A Pilot Study of the Safety and Usability of the Obsidian Blockchain Programming Language

Authors: Gauri Kambhatla, Michael Coblenz, Reed Oei, Joshua Sunshine, Jonathan Aldrich, and Brad A. Myers

Published in: OASIcs, Volume 76, 10th Workshop on Evaluation and Usability of Programming Languages and Tools (PLATEAU 2019)


Abstract
Although blockchains have been proposed for building systems that execute critical transactions, security vulnerabilities have plagued programs that are deployed on blockchain systems. The programming language Obsidian was developed with the purpose of statically preventing some of the more common of these security risks, specifically the loss of resources and improper manipulation of objects. The question then is whether Obsidian’s novel features impact the usability of the language. In this paper, we begin to evaluate Obsidian with respect to usability, and develop materials for a quantitative user study through a sequence of pilot studies. Specifically, our goal was to assess a) potential usability problems of Obsidian, b) the effectiveness of a tutorial for participants to learn the language, and c) the design of programming tasks to evaluate performance using the language. Our preliminary results tentatively suggest that the complexity of Obsidian’s features do not hinder usability, although these results will be validated in the quantitative study. We also observed the following factors as being important in a given programmer’s ability to learn Obsidian: a) integrating very frequent opportunities for practice of the material - e.g., after less than a page of material at a time, and b) previous programming experience and self-efficacy.

Cite as

Gauri Kambhatla, Michael Coblenz, Reed Oei, Joshua Sunshine, Jonathan Aldrich, and Brad A. Myers. A Pilot Study of the Safety and Usability of the Obsidian Blockchain Programming Language. In 10th Workshop on Evaluation and Usability of Programming Languages and Tools (PLATEAU 2019). Open Access Series in Informatics (OASIcs), Volume 76, pp. 2:1-2:11, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2020)


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@InProceedings{kambhatla_et_al:OASIcs.PLATEAU.2019.2,
  author =	{Kambhatla, Gauri and Coblenz, Michael and Oei, Reed and Sunshine, Joshua and Aldrich, Jonathan and Myers, Brad A.},
  title =	{{A Pilot Study of the Safety and Usability of the Obsidian Blockchain Programming Language}},
  booktitle =	{10th Workshop on Evaluation and Usability of Programming Languages and Tools (PLATEAU 2019)},
  pages =	{2:1--2:11},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-95977-135-1},
  ISSN =	{2190-6807},
  year =	{2020},
  volume =	{76},
  editor =	{Chasins, Sarah and Glassman, Elena L. and Sunshine, Joshua},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/OASIcs.PLATEAU.2019.2},
  URN =		{urn:nbn:de:0030-drops-119564},
  doi =		{10.4230/OASIcs.PLATEAU.2019.2},
  annote =	{Keywords: smart contracts, programming language user study, language usability}
}
Document
A Capability-Based Module System for Authority Control (Artifact)

Authors: Darya Melicher, Yangqingwei Shi, Alex Potanin, and Jonathan Aldrich

Published in: DARTS, Volume 3, Issue 2, Special Issue of the 31st European Conference on Object-Oriented Programming (ECOOP 2017)


Abstract
This artifact is intended to demonstrate the module system of the Wyvern programming language and consists of a Linux virtual machine with a snapshot of the Wyvern programming language's codebase. The Wyvern codebase contains a test suite that corresponds to the code examples in the paper accompanying the artifact. In addition, the artifact contains a document describing how to compile and run Wyvern programs.

Cite as

Darya Melicher, Yangqingwei Shi, Alex Potanin, and Jonathan Aldrich. A Capability-Based Module System for Authority Control (Artifact). In Special Issue of the 31st European Conference on Object-Oriented Programming (ECOOP 2017). Dagstuhl Artifacts Series (DARTS), Volume 3, Issue 2, pp. 2:1-2:2, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017)


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@Article{melicher_et_al:DARTS.3.2.2,
  author =	{Melicher, Darya and Shi, Yangqingwei and Potanin, Alex and Aldrich, Jonathan},
  title =	{{A Capability-Based Module System for Authority Control (Artifact)}},
  pages =	{2:1--2:2},
  journal =	{Dagstuhl Artifacts Series},
  ISSN =	{2509-8195},
  year =	{2017},
  volume =	{3},
  number =	{2},
  editor =	{Melicher, Darya and Shi, Yangqingwei and Potanin, Alex and Aldrich, Jonathan},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/DARTS.3.2.2},
  URN =		{urn:nbn:de:0030-drops-72838},
  doi =		{10.4230/DARTS.3.2.2},
  annote =	{Keywords: language-based security, capabilities, authority, modules}
}
Document
A Capability-Based Module System for Authority Control

Authors: Darya Melicher, Yangqingwei Shi, Alex Potanin, and Jonathan Aldrich

Published in: LIPIcs, Volume 74, 31st European Conference on Object-Oriented Programming (ECOOP 2017)


Abstract
The principle of least authority states that each component of the system should be given authority to access only the information and resources that it needs for its operation. This principle is fundamental to the secure design of software systems, as it helps to limit an application's attack surface and to isolate vulnerabilities and faults. Unfortunately, current programming languages do not provide adequate help in controlling the authority of application modules, an issue that is particularly acute in the case of untrusted third-party extensions. In this paper, we present a language design that facilitates controlling the authority granted to each application module. The key technical novelty of our approach is that modules are first-class, statically typed capabilities. First-class modules are essentially objects, and so we formalize our module system by translation into an object calculus and prove that the core calculus is type-safe and authority-safe. Unlike prior formalizations, our work defines authority non-transitively, allowing engineers to reason about software designs that use wrappers to provide an attenuated version of a more powerful capability. Our approach allows developers to determine a module's authority by examining the capabilities passed as module arguments when the module is created, or delegated to the module later during execution. The type system facilitates this by identifying which objects provide capabilities to sensitive resources, and by enabling security architects to examine the capabilities passed into and out of a module based only on the module's interface, without needing to examine the module's implementation code. An implementation of the module system and illustrative examples in the Wyvern programming language suggest that our approach can be a practical way to control module authority.

Cite as

Darya Melicher, Yangqingwei Shi, Alex Potanin, and Jonathan Aldrich. A Capability-Based Module System for Authority Control. In 31st European Conference on Object-Oriented Programming (ECOOP 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 74, pp. 20:1-20:27, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017)


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@InProceedings{melicher_et_al:LIPIcs.ECOOP.2017.20,
  author =	{Melicher, Darya and Shi, Yangqingwei and Potanin, Alex and Aldrich, Jonathan},
  title =	{{A Capability-Based Module System for Authority Control}},
  booktitle =	{31st European Conference on Object-Oriented Programming (ECOOP 2017)},
  pages =	{20:1--20:27},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-035-4},
  ISSN =	{1868-8969},
  year =	{2017},
  volume =	{74},
  editor =	{M\"{u}ller, Peter},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ECOOP.2017.20},
  URN =		{urn:nbn:de:0030-drops-72709},
  doi =		{10.4230/LIPIcs.ECOOP.2017.20},
  annote =	{Keywords: Language-based security, capabilities, authority, modules}
}
Document
Toward Semantic Foundations for Program Editors

Authors: Cyrus Omar, Ian Voysey, Michael Hilton, Joshua Sunshine, Claire Le Goues, Jonathan Aldrich, and Matthew A. Hammer

Published in: LIPIcs, Volume 71, 2nd Summit on Advances in Programming Languages (SNAPL 2017)


Abstract
Programming language definitions assign formal meaning to complete programs. Programmers, however, spend a substantial amount of time interacting with incomplete programs - programs with holes, type inconsistencies and binding inconsistencies - using tools like program editors and live programming environments (which interleave editing and evaluation). Semanticists have done comparatively little to formally characterize (1) the static and dynamic semantics of incomplete programs; (2) the actions available to programmers as they edit and inspect incomplete programs; and (3) the behavior of editor services that suggest likely edit actions to the programmer based on semantic information extracted from the incomplete program being edited, and from programs that the system has encountered in the past. This paper serves as a vision statement for a research program that seeks to develop these "missing" semantic foundations. Our hope is that these contributions, which will take the form of a series of simple formal calculi equipped with a tractable metatheory, will guide the design of a variety of current and future interactive programming tools, much as various lambda calculi have guided modern language designs. Our own research will apply these principles in the design of Hazel, an experimental live lab notebook programming environment designed for data science tasks. We plan to co-design the Hazel language with the editor so that we can explore concepts such as edit-time semantic conflict resolution mechanisms and mechanisms that allow library providers to install library-specific editor services.

Cite as

Cyrus Omar, Ian Voysey, Michael Hilton, Joshua Sunshine, Claire Le Goues, Jonathan Aldrich, and Matthew A. Hammer. Toward Semantic Foundations for Program Editors. In 2nd Summit on Advances in Programming Languages (SNAPL 2017). Leibniz International Proceedings in Informatics (LIPIcs), Volume 71, pp. 11:1-11:12, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2017)


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@InProceedings{omar_et_al:LIPIcs.SNAPL.2017.11,
  author =	{Omar, Cyrus and Voysey, Ian and Hilton, Michael and Sunshine, Joshua and Le Goues, Claire and Aldrich, Jonathan and Hammer, Matthew A.},
  title =	{{Toward Semantic Foundations for Program Editors}},
  booktitle =	{2nd Summit on Advances in Programming Languages (SNAPL 2017)},
  pages =	{11:1--11:12},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-032-3},
  ISSN =	{1868-8969},
  year =	{2017},
  volume =	{71},
  editor =	{Lerner, Benjamin S. and Bod{\'\i}k, Rastislav and Krishnamurthi, Shriram},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.SNAPL.2017.11},
  URN =		{urn:nbn:de:0030-drops-71273},
  doi =		{10.4230/LIPIcs.SNAPL.2017.11},
  annote =	{Keywords: program editors, type systems, live programming, program prediction}
}
Document
Composing Interfering Abstract Protocols

Authors: Filipe Militão, Jonathan Aldrich, and Luís Caires

Published in: LIPIcs, Volume 56, 30th European Conference on Object-Oriented Programming (ECOOP 2016)


Abstract
The undisciplined use of shared mutable state can be a source of program errors when aliases unsafely interfere with each other. While protocol-based techniques to reason about interference abound, they do not address two practical concerns: the decidability of protocol composition and its integration with protocol abstraction. We show that our composition procedure is decidable and that it ensures safe interference even when composing abstract protocols. To evaluate the expressiveness of our protocol framework for safe shared memory interference, we show how this same protocol framework can be used to model safe, typeful message-passing concurrency idioms.

Cite as

Filipe Militão, Jonathan Aldrich, and Luís Caires. Composing Interfering Abstract Protocols. In 30th European Conference on Object-Oriented Programming (ECOOP 2016). Leibniz International Proceedings in Informatics (LIPIcs), Volume 56, pp. 16:1-16:26, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2016)


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@InProceedings{militao_et_al:LIPIcs.ECOOP.2016.16,
  author =	{Milit\~{a}o, Filipe and Aldrich, Jonathan and Caires, Lu{\'\i}s},
  title =	{{Composing Interfering Abstract Protocols}},
  booktitle =	{30th European Conference on Object-Oriented Programming (ECOOP 2016)},
  pages =	{16:1--16:26},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-014-9},
  ISSN =	{1868-8969},
  year =	{2016},
  volume =	{56},
  editor =	{Krishnamurthi, Shriram and Lerner, Benjamin S.},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ECOOP.2016.16},
  URN =		{urn:nbn:de:0030-drops-61108},
  doi =		{10.4230/LIPIcs.ECOOP.2016.16},
  annote =	{Keywords: shared memory interference, protocol composition, aliasing, linearity}
}
Document
A Theory of Tagged Objects (Artifact)

Authors: Joseph Lee, Jonathan Aldrich, Troy Shaw, Alex Potanin, and Benjamin Chung

Published in: DARTS, Volume 1, Issue 1, Special Issue of the 29th European Conference on Object-Oriented Programming (ECOOP 2015)


Abstract
A compiler and interpreter for Wyvern programming language written in Java and hosted on http://github.com/wyvernlang/wyvern and some sample programs (.wyv) including the main example from the paper in borderedwindow.wyv. We also include an extract of all the unit tests of which a large number may be designed to fail -- therefore they are best run using JUnit which can be done by checking out the source tree from the GitHub project link above.

Cite as

Joseph Lee, Jonathan Aldrich, Troy Shaw, Alex Potanin, and Benjamin Chung. A Theory of Tagged Objects (Artifact). In Special Issue of the 29th European Conference on Object-Oriented Programming (ECOOP 2015). Dagstuhl Artifacts Series (DARTS), Volume 1, Issue 1, pp. 3:1-3:3, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2015)


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@Article{lee_et_al:DARTS.1.1.3,
  author =	{Lee, Joseph and Aldrich, Jonathan and Shaw, Troy and Potanin, Alex and Chung, Benjamin},
  title =	{{A Theory of Tagged Objects (Artifact)}},
  pages =	{3:1--3:3},
  journal =	{Dagstuhl Artifacts Series},
  ISSN =	{2509-8195},
  year =	{2015},
  volume =	{1},
  number =	{1},
  editor =	{Lee, Joseph and Aldrich, Jonathan and Shaw, Troy and Potanin, Alex and Chung, Benjamin},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/DARTS.1.1.3},
  URN =		{urn:nbn:de:0030-drops-55121},
  doi =		{10.4230/DARTS.1.1.3},
  annote =	{Keywords: objects, classes, tags, nominal and structural types}
}
Document
A Theory of Tagged Objects

Authors: Joseph Lee, Jonathan Aldrich, Troy Shaw, and Alex Potanin

Published in: LIPIcs, Volume 37, 29th European Conference on Object-Oriented Programming (ECOOP 2015)


Abstract
Foundational models of object-oriented constructs typically model objects as records with a structural type. However, many object-oriented languages are class-based; statically-typed formal models of these languages tend to sacrifice the foundational nature of the record-based models, and in addition cannot express dynamic class loading or creation. In this paper, we explore how to model statically-typed object-oriented languages that support dynamic class creation using foundational constructs of type theory. We start with an extensible tag construct motivated by type theory, and adapt it to support static reasoning about class hierarchy and the tags supported by each object. The result is a model that better explains the relationship between object-oriented and functional programming paradigms, suggests a useful enhancement to functional programming languages, and paves the way for more expressive statically typed object-oriented languages. In that vein, we describe the design and implementation of the Wyvern language, which leverages our theory.

Cite as

Joseph Lee, Jonathan Aldrich, Troy Shaw, and Alex Potanin. A Theory of Tagged Objects. In 29th European Conference on Object-Oriented Programming (ECOOP 2015). Leibniz International Proceedings in Informatics (LIPIcs), Volume 37, pp. 174-197, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2015)


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@InProceedings{lee_et_al:LIPIcs.ECOOP.2015.174,
  author =	{Lee, Joseph and Aldrich, Jonathan and Shaw, Troy and Potanin, Alex},
  title =	{{A Theory of Tagged Objects}},
  booktitle =	{29th European Conference on Object-Oriented Programming (ECOOP 2015)},
  pages =	{174--197},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-939897-86-6},
  ISSN =	{1868-8969},
  year =	{2015},
  volume =	{37},
  editor =	{Boyland, John Tang},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ECOOP.2015.174},
  URN =		{urn:nbn:de:0030-drops-52305},
  doi =		{10.4230/LIPIcs.ECOOP.2015.174},
  annote =	{Keywords: objects, classes, tags, nominal and structural types}
}
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