Article

Modular type classes

Authors:

Manuel M. T. Chakravarty,

Gabriele KellerAuthors Info & Claims

POPL '07: Proceedings of the 34th annual ACM SIGPLAN-SIGACT symposium on Principles of programming languages

Pages 63 - 70

https://doi.org/10.1145/1190216.1190229

Published: 17 January 2007 Publication History

Abstract

ML modules and Haskell type classes have proven to be highly effective tools for program structuring. Modules emphasize explicit configuration of program components and the use of data abstraction. Type classes emphasize implicit program construction and ad hoc polymorphism. In this paper, we show how the implicitly-typed style of type class programming may be supported within the framework of an explicitly-typed module language by viewing type classes as a particular mode of use of modules. This view offers a harmonious integration of modules and type classes, where type class features, such as class hierarchies and associated types, arise naturally as uses of existing module-language constructs, such as module hierarchies and type components. In addition, programmers have explicit control over which type class instances are available for use by type inference in a given scope. We formalize our approach as a Harper-Stone-style elaboration relation, and provide a sound type inference algorithm as a guide to implementation.

References

[1]

Manuel M. T. Chakravarty, Gabriele Keller, and Simon Peyton Jones. Associated type synonyms. In ICFP '05.]]

Digital Library

[2]

Manuel M. T. Chakravarty, Gabriele Keller, Simon Peyton Jones, and Simon Marlow. Associated types with class. In POPL '05.]]

Digital Library

[3]

Luis Damas and Robin Milner. Principal type schemes for functional programs. In POPL '82.]]

Digital Library

[4]

Derek Dreyer. Understanding and Evolving the ML Module System. PhD thesis, Carnegie Mellon University, Pittsburgh, PA, May 2005.]]

Digital Library

[5]

Derek Dreyer and Matthias Blume. Principal type schemes for modular programs. Technical Report TR-2006-08, University of Chicago Comp. Sci. Dept., October 2006.]]

[6]

Derek Dreyer, Karl Crary, and Robert Harper. A type system for higher-order modules. In POPL '03.]]

Digital Library

[7]

Derek Dreyer, Robert Harper, Manuel M.T. Chakravarty, and Gabriele Keller. Modular type classes. Technical Report TR-2006-09, University of Chicago Comp. Sci. Dept., October 2006.]]

[8]

Robert Harper, John C. Mitchell, and Eugenio Moggi. Higher-order modules and the phase distinction. In POPL '90.]]

Digital Library

[9]

Robert Harper and Chris Stone. A type-theoretic interpretation of Standard ML. In G. Plotkin, C. Stirling, and M. Tofte, editors, Proof, Language, and Interaction: Essays in Honor of Robin Milner. MIT Press, 2000.]]

Digital Library

[10]

Mark P. Jones. Simplifying and improving qualified types. In FPCA '95.]]

Digital Library

[11]

Mark P. Jones. A theory of qualified types. In ESOP '92.]]

Digital Library

[12]

Mark P. Jones. Type classes with functional dependencies. In ESOP'00.]]

Digital Library

[13]

Mark P. Jones. Using parameterized signatures to express modular structure. In POPL '96.]]

Digital Library

[14]

Mark P. Jones. Qualified Types: Theory and Practice. Cambridge University Press, 1994.]]

Digital Library

[15]

Mark P. Jones. A system of constructor classes: Overloading and implicit higher-order polymorphism. Journal of Functional Programming, 5(1), 1995.]]

[16]

Wolfram Kahl and Jan Scheffczyk. Named instances for Haskell type classes. In Haskell Workshop, 2001.]]

[17]

David MacQueen. Modules for Standard ML. In LFP '84.]]

Digital Library

[18]

Robin Milner, Mads Tofte, Robert Harper, and David MacQueen. The Definition of Standard ML (Revised). MIT Press, 1997.]]

Digital Library

[19]

Simon Peyton Jones et al. Haskell 98 language and libraries: the revised report. Journal of Functional Programming, 13(1), 2003.]]

[20]

Gerhard Schneider. ML mit Typklassen. Master's thesis, June 2000.]]

[21]

Jeremy Siek. A Language for Generic Programming. PhD thesis, Indiana University, August 2005.]]

Digital Library

[22]

Jeremy Siek and Andrew Lumsdaine. Essential language support for generic programming. In PLDI'05.]]

Digital Library

[23]

P. Wadler and S. Blott. How to make ad-hoc polymorphism less ad-hoc. In POPL '89.]]

Digital Library

[24]

Stefan Wehr. ML modules and Haskell type classes: A constructive comparison. Master's thesis, Albert-Ludwigs-Universität Freiburg, Institut für Informatik, 2005.]]

Cited By

Sterling JHarper R(2021)Logical Relations as Types: Proof-Relevant Parametricity for Program ModulesJournal of the ACM10.1145/347483468:6(1-47)Online publication date: 5-Oct-2021
https://dl.acm.org/doi/10.1145/3474834
Jones MMorris JEisenberg R(2019)Partial type constructors: or, making ad hoc datatypes less ad hocProceedings of the ACM on Programming Languages10.1145/33711084:POPL(1-28)Online publication date: 20-Dec-2019
https://dl.acm.org/doi/10.1145/3371108
Bottu GXie NMarntirosian KSchrijvers T(2019)Coherence of type class resolutionProceedings of the ACM on Programming Languages10.1145/33416953:ICFP(1-28)Online publication date: 26-Jul-2019
https://dl.acm.org/doi/10.1145/3341695
Show More Cited By

Index Terms

Modular type classes
1. Software and its engineering
  1. Software notations and tools
    1. Formal language definitions
    2. General programming languages
      1. Language features
        Modules / packages
        Polymorphism
2. Theory of computation
  1. Formal languages and automata theory
  2. Semantics and reasoning
    1. Program constructs
      1. Type structures

Recommendations

Modular type classes
Proceedings of the 2007 POPL Conference

ML modules and Haskell type classes have proven to be highly effective tools for program structuring. Modules emphasize explicit configuration of program components and the use of data abstraction. Type classes emphasize implicit program construction ...
Bidirectional type class instances
Haskell 2019: Proceedings of the 12th ACM SIGPLAN International Symposium on Haskell

GADTs were introduced in Haskell’s eco-system more than a decade ago, but their interaction with several mainstream features such as type classes and functional dependencies has a lot of room for improvement. More specifically, for some GADTs it can be ...
Associated type synonyms
Proceedings of the tenth ACM SIGPLAN international conference on Functional programming

Haskell programmers often use a multi-parameter type class in which one or more type parameters are functionally dependent on the first. Although such functional dependencies have proved quite popular in practice, they express the programmer's intent ...

Comments

Information & Contributors

Information

Published In

cover image ACM Conferences

POPL '07: Proceedings of the 34th annual ACM SIGPLAN-SIGACT symposium on Principles of programming languages

January 2007

400 pages

ISBN:1595935754

DOI:10.1145/1190216

General Chair:
Martin Hofmann
Ludwig-Maximilians U, Munich, Germany
,
Program Chair:
Matthias Felleisen
Northeastern University, Boston MA

ACM SIGPLAN Notices Volume 42, Issue 1
Proceedings of the 2007 POPL Conference
January 2007
379 pages
ISSN:0362-1340
EISSN:1558-1160
DOI:10.1145/1190215
Issue’s Table of Contents

Copyright © 2007 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 ACM 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]

Sponsors

Publisher

Association for Computing Machinery

New York, NY, United States

Publication History

Published: 17 January 2007

Permissions

Request permissions for this article.

Request Permissions

Check for updates

Author Tags

Qualifiers

Article

Conference

POPL07

Sponsor:

POPL07: The 34th Annual ACM SIGPLAN-SIGACT Symposium on Principles of Programming Languages

January 17 - 19, 2007

Nice, France

Acceptance Rates

Overall Acceptance Rate 824 of 4,130 submissions, 20%

Upcoming Conference

Contributors

Other Metrics

View Article Metrics

Bibliometrics & Citations

Bibliometrics

Article Metrics

31
Total Citations
View Citations
675
Total Downloads

Downloads (Last 12 months)51
Downloads (Last 6 weeks)1

Reflects downloads up to 04 Feb 2025

Other Metrics

View Author Metrics

Citations

Cited By

Sterling JHarper R(2021)Logical Relations as Types: Proof-Relevant Parametricity for Program ModulesJournal of the ACM10.1145/347483468:6(1-47)Online publication date: 5-Oct-2021
https://dl.acm.org/doi/10.1145/3474834
Jones MMorris JEisenberg R(2019)Partial type constructors: or, making ad hoc datatypes less ad hocProceedings of the ACM on Programming Languages10.1145/33711084:POPL(1-28)Online publication date: 20-Dec-2019
https://dl.acm.org/doi/10.1145/3371108
Bottu GXie NMarntirosian KSchrijvers T(2019)Coherence of type class resolutionProceedings of the ACM on Programming Languages10.1145/33416953:ICFP(1-28)Online publication date: 26-Jul-2019
https://dl.acm.org/doi/10.1145/3341695
SCHRIJVERS TOLIVEIRA BWADLER PMARNTIROSIAN K(2019)COCHIS: Stable and coherent implicitsJournal of Functional Programming10.1017/S095679681800024229Online publication date: 8-Feb-2019
https://doi.org/10.1017/S0956796818000242
Elsman MHenriksen TAnnenkov DOancea C(2018)Static interpretation of higher-order modules in Futhark: functional GPU programming in the largeProceedings of the ACM on Programming Languages10.1145/32367922:ICFP(1-30)Online publication date: 30-Jul-2018
https://dl.acm.org/doi/10.1145/3236792
ROSSBERG A(2018)1ML – Core and modules unitedJournal of Functional Programming10.1017/S095679681800020528Online publication date: 27-Dec-2018
https://doi.org/10.1017/S0956796818000205
Chang AMiller HHaller PLhoták O(2017)The limitations of type classes as subtyped implicits (short paper)Proceedings of the 8th ACM SIGPLAN International Symposium on Scala10.1145/3136000.3136006(8-12)Online publication date: 22-Oct-2017
https://dl.acm.org/doi/10.1145/3136000.3136006
Zhang YMyers A(2017)Familia: unifying interfaces, type classes, and family polymorphismProceedings of the ACM on Programming Languages10.1145/31338941:OOPSLA(1-31)Online publication date: 12-Oct-2017
https://dl.acm.org/doi/10.1145/3133894
Morris JEisenberg R(2017)Constrained type familiesProceedings of the ACM on Programming Languages10.1145/31102861:ICFP(1-28)Online publication date: 29-Aug-2017
https://dl.acm.org/doi/10.1145/3110286
White LBour FYallop J(2015)Modular implicitsElectronic Proceedings in Theoretical Computer Science10.4204/EPTCS.198.2198(22-63)Online publication date: 5-Dec-2015
https://doi.org/10.4204/EPTCS.198.2
Show More Cited By

View Options

Login options

Check if you have access through your login credentials or your institution to get full access on this article.

Full Access

Get this Publication

View options

PDF

View or Download as a PDF file.

eReader

View online with eReader.

Figures

Tables

Media

View Table of Conten