research-article

GADTs meet their match: pattern-matching warnings that account for GADTs, guards, and laziness

Authors:

Georgios Karachalias,

Tom Schrijvers,

Dimitrios Vytiniotis,

Simon Peyton JonesAuthors Info & Claims

ICFP 2015: Proceedings of the 20th ACM SIGPLAN International Conference on Functional Programming

Pages 424 - 436

https://doi.org/10.1145/2784731.2784748

Published: 29 August 2015 Publication History

Abstract

For ML and Haskell, accurate warnings when a function definition has redundant or missing patterns are mission critical. But today's compilers generate bogus warnings when the programmer uses guards (even simple ones), GADTs, pattern guards, or view patterns. We give the first algorithm that handles all these cases in a single, uniform framework, together with an implementation in GHC, and evidence of its utility in practice.

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Cited By

Baudon TRadanne GGonnord L(2023)Bit-Stealing Made Legal: Compilation for Custom Memory Representations of Algebraic Data TypesProceedings of the ACM on Programming Languages10.1145/36078587:ICFP(813-846)Online publication date: 31-Aug-2023
https://dl.acm.org/doi/10.1145/3607858
Yuan YGuest SGriffis EPotter HMoon DOmar C(2023)Live Pattern Matching with Typed HolesProceedings of the ACM on Programming Languages10.1145/35860487:OOPSLA1(609-635)Online publication date: 6-Apr-2023
https://dl.acm.org/doi/10.1145/3586048
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
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Index Terms

GADTs meet their match: pattern-matching warnings that account for GADTs, guards, and laziness
1. Software and its engineering
  1. Software notations and tools
    1. General programming languages
      1. Language features
      2. Language types

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cover image ACM Conferences

ICFP 2015: Proceedings of the 20th ACM SIGPLAN International Conference on Functional Programming

August 2015

436 pages

ISBN:9781450336697

DOI:10.1145/2784731

General Chair:
Kathleen Fisher
Tufts University, USA
,
Program Chair:
John Reppy
University of Chicago, USA

ACM SIGPLAN Notices Volume 50, Issue 9
ICFP '15
September 2015
436 pages
ISSN:0362-1340
EISSN:1558-1160
DOI:10.1145/2858949
Editor:
Andy Gill
University of Kansas, Lawrence, KS
Issue’s Table of Contents

Copyright © 2015 ACM.

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Published: 29 August 2015

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ICFP'15: 20th ACM SIGPLAN International Conference on Functional Programming

August 31 - September 2, 2015

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Cited By

Baudon TRadanne GGonnord L(2023)Bit-Stealing Made Legal: Compilation for Custom Memory Representations of Algebraic Data TypesProceedings of the ACM on Programming Languages10.1145/36078587:ICFP(813-846)Online publication date: 31-Aug-2023
https://dl.acm.org/doi/10.1145/3607858
Yuan YGuest SGriffis EPotter HMoon DOmar C(2023)Live Pattern Matching with Typed HolesProceedings of the ACM on Programming Languages10.1145/35860487:OOPSLA1(609-635)Online publication date: 6-Apr-2023
https://dl.acm.org/doi/10.1145/3586048
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
Zilberstein NSchrijvers T(2020)Eliminating bugs with dependent Haskell (experience report)Proceedings of the 13th ACM SIGPLAN International Symposium on Haskell10.1145/3406088.3409020(9-16)Online publication date: 27-Aug-2020
https://dl.acm.org/doi/10.1145/3406088.3409020
Osera PDarais DGibbons J(2019)Constraint-based type-directed program synthesisProceedings of the 4th ACM SIGPLAN International Workshop on Type-Driven Development10.1145/3331554.3342608(64-76)Online publication date: 18-Aug-2019
https://dl.acm.org/doi/10.1145/3331554.3342608
Dunfield JKrishnaswami N(2019)Sound and complete bidirectional typechecking for higher-rank polymorphism with existentials and indexed typesProceedings of the ACM on Programming Languages10.1145/32903223:POPL(1-28)Online publication date: 2-Jan-2019
https://dl.acm.org/doi/10.1145/3290322
Garrigue JLe Normand J(2017)GADTs and Exhaustiveness: Looking for the ImpossibleElectronic Proceedings in Theoretical Computer Science10.4204/EPTCS.241.2241(23-35)Online publication date: 7-Feb-2017
https://doi.org/10.4204/EPTCS.241.2
Chen SErwig M(2016)Principal type inference for GADTsACM SIGPLAN Notices10.1145/2914770.283766551:1(416-428)Online publication date: 11-Jan-2016
https://dl.acm.org/doi/10.1145/2914770.2837665
Chen SErwig MBodik RMajumdar R(2016)Principal type inference for GADTsProceedings of the 43rd Annual ACM SIGPLAN-SIGACT Symposium on Principles of Programming Languages10.1145/2837614.2837665(416-428)Online publication date: 11-Jan-2016
https://dl.acm.org/doi/10.1145/2837614.2837665
He X(2019)Overview of generalized algebraic data types in OCaml2019 5TH INTERNATIONAL CONFERENCE ON GREEN POWER, MATERIALS AND MANUFACTURING TECHNOLOGY AND APPLICATIONS (GPMMTA 2019)10.1063/1.5137873(020029)Online publication date: 2019
https://doi.org/10.1063/1.5137873

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