short-paper

Towards improved GADT reasoning in Scala

Authors:

Lionel Parreaux,

Aleksander Boruch-Gruszecki,

Paolo G. GiarrussoAuthors Info & Claims

Scala '19: Proceedings of the Tenth ACM SIGPLAN Symposium on Scala

Pages 12 - 16

https://doi.org/10.1145/3337932.3338813

Published: 17 July 2019 Publication History

Abstract

Generalized algebraic data types (GADT) have been notoriously difficult to implement correctly in Scala. Both major Scala compilers, Scalac and Dotty, are currently known to have type soundness holes related to them. In particular, covariant GADTs have exposed paradoxes due to Scala's inheritance model. We informally explore foundations for GADTs within Scala's core type system, to guide a principled understanding and implementation of GADTs in Scala.

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Cited By

Parreaux LBoruch-Gruszecki AFan AChau C(2024)When Subtyping Constraints Liberate: A Novel Type Inference Approach for First-Class PolymorphismProceedings of the ACM on Programming Languages10.1145/36328908:POPL(1418-1450)Online publication date: 5-Jan-2024
https://dl.acm.org/doi/10.1145/3632890
van der Rest CPoulsen CRouvoet AVisser EMosses P(2022)Intrinsically-typed definitional interpreters à la carteProceedings of the ACM on Programming Languages10.1145/35633556:OOPSLA2(1903-1932)Online publication date: 31-Oct-2022
https://dl.acm.org/doi/10.1145/3563355
Boruch-Gruszecki AWaśko RXu YParreaux L(2022)A case for DOT: theoretical foundations for objects with pattern matching and GADT-style reasoningProceedings of the ACM on Programming Languages10.1145/35633426:OOPSLA2(1526-1555)Online publication date: 31-Oct-2022
https://dl.acm.org/doi/10.1145/3563342
Show More Cited By

Index Terms

Towards improved GADT reasoning in Scala
1. Software and its engineering
  1. Software notations and tools
    1. General programming languages
      1. Language features
        Classes and objects
        Data types and structures

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cover image ACM Conferences

Scala '19: Proceedings of the Tenth ACM SIGPLAN Symposium on Scala

July 2019

37 pages

ISBN:9781450368247

DOI:10.1145/3337932

Copyright © 2019 ACM.

Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than the author(s) must be honored. Abstracting with credit is permitted. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from [email protected].

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SIGPLAN: ACM Special Interest Group on Programming Languages

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New York, NY, United States

Publication History

Published: 17 July 2019

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Short-paper

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Scala '19

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SIGPLAN

Scala '19: Tenth ACM SIGPLAN Scala Symposium

July 17, 2019

London, United Kingdom

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Scala '19 Paper Acceptance Rate 5 of 6 submissions, 83%;

Overall Acceptance Rate 5 of 6 submissions, 83%

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Cited By

Parreaux LBoruch-Gruszecki AFan AChau C(2024)When Subtyping Constraints Liberate: A Novel Type Inference Approach for First-Class PolymorphismProceedings of the ACM on Programming Languages10.1145/36328908:POPL(1418-1450)Online publication date: 5-Jan-2024
https://dl.acm.org/doi/10.1145/3632890
van der Rest CPoulsen CRouvoet AVisser EMosses P(2022)Intrinsically-typed definitional interpreters à la carteProceedings of the ACM on Programming Languages10.1145/35633556:OOPSLA2(1903-1932)Online publication date: 31-Oct-2022
https://dl.acm.org/doi/10.1145/3563355
Boruch-Gruszecki AWaśko RXu YParreaux L(2022)A case for DOT: theoretical foundations for objects with pattern matching and GADT-style reasoningProceedings of the ACM on Programming Languages10.1145/35633426:OOPSLA2(1526-1555)Online publication date: 31-Oct-2022
https://dl.acm.org/doi/10.1145/3563342
Xu YBoruch-Gruszecki AParreaux LRichard-Foy JDoeraene S(2021)Implementing path-dependent GADT reasoning for Scala 3Proceedings of the 12th ACM SIGPLAN International Symposium on Scala10.1145/3486610.3486892(22-32)Online publication date: 17-Oct-2021
https://dl.acm.org/doi/10.1145/3486610.3486892
Stucki SGiarrusso P(2021)A theory of higher-order subtyping with type intervalsProceedings of the ACM on Programming Languages10.1145/34735745:ICFP(1-30)Online publication date: 19-Aug-2021
https://dl.acm.org/doi/10.1145/3473574

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