research-article

Self type constructors

Authors:

Atsushi IgarashiAuthors Info & Claims

ACM SIGPLAN Notices, Volume 44, Issue 10

Pages 263 - 282

https://doi.org/10.1145/1639949.1640109

Published: 25 October 2009 Publication History

Abstract

Bruce and Foster proposed the language LOOJ, an extension of Java with the notion of MyType, which represents the type of a self reference and changes its meaning along with inheritance. MyType is useful to write extensible yet type-safe classes for objects with recursive interfaces, that is, ones with methods that take or return objects of the same type as the receiver.

Although LOOJ has also generics, MyType has been introduced as a feature rather orthogonal to generics. As a result, LOOJ cannot express an interface that refers to the same generic class recursively but with different type arguments. This is a significant limitation because such an interface naturally arises in practice, for example, in a generic collection class with method map(), which converts a collection to the same kind of collection of a different element type. Altherr and Cremet and Moors, Piessens, and Odersky gave solutions to this problem but they used a highly sophisticated combination of advanced mechanisms such as abstract type members, higher-order type constructors, and F-bounded polymorphism.

In this paper, we give another solution by introducing self type constructors, which integrate MyType and generics so that MyType can take type arguments in a generic class. Self type constructors are tailored to writing recursive interfaces more concicely than previous solutions. We demonstrate the expressive power of self type constructors by means of examples, formalize a core language with self type constructors, and prove its type safety.

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Cited By

Winther JSchwartzbach M(2011)Related typesProceedings of the 25th European conference on Object-oriented programming10.5555/2032497.2032528(434-458)Online publication date: 25-Jul-2011
https://dl.acm.org/doi/10.5555/2032497.2032528
Winther JSchwartzbach M(2011)Related TypesECOOP 2011 – Object-Oriented Programming10.1007/978-3-642-22655-7_21(434-458)Online publication date: 2011
https://doi.org/10.1007/978-3-642-22655-7_21
Allende ECallaú OFabry JTanter ÉDenker M(2019)Gradual typing for SmalltalkScience of Computer Programming10.1016/j.scico.2013.06.00696:P1(52-69)Online publication date: 1-Jan-2019
https://dl.acm.org/doi/10.1016/j.scico.2013.06.006
Show More Cited By

Index Terms

Self type constructors
1. Software and its engineering
  1. Software notations and tools
    1. General programming languages
      1. Language features
        Classes and objects
      2. Language types
        Object oriented languages

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Published In

cover image ACM SIGPLAN Notices

ACM SIGPLAN Notices Volume 44, Issue 10

OOPSLA '09

October 2009

554 pages

ISSN:0362-1340

EISSN:1558-1160

DOI:10.1145/1639949

Issue’s Table of Contents

OOPSLA '09: Proceedings of the 24th ACM SIGPLAN conference on Object oriented programming systems languages and applications
October 2009
590 pages
ISBN:9781605587660
DOI:10.1145/1640089
General Chair:
Shail Arora
Adayana, Inc.
,
Program Chair:
Gary Leavens
University of Central Florida

Copyright © 2009 ACM.

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Association for Computing Machinery

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Publication History

Published: 25 October 2009

Published in SIGPLAN Volume 44, Issue 10

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Cited By

Winther JSchwartzbach M(2011)Related typesProceedings of the 25th European conference on Object-oriented programming10.5555/2032497.2032528(434-458)Online publication date: 25-Jul-2011
https://dl.acm.org/doi/10.5555/2032497.2032528
Winther JSchwartzbach M(2011)Related TypesECOOP 2011 – Object-Oriented Programming10.1007/978-3-642-22655-7_21(434-458)Online publication date: 2011
https://doi.org/10.1007/978-3-642-22655-7_21
Allende ECallaú OFabry JTanter ÉDenker M(2019)Gradual typing for SmalltalkScience of Computer Programming10.1016/j.scico.2013.06.00696:P1(52-69)Online publication date: 1-Jan-2019
https://dl.acm.org/doi/10.1016/j.scico.2013.06.006
Allende EFabry JTanter É(2013)Cast insertion strategies for gradually-typed objectsACM SIGPLAN Notices10.1145/2578856.250817149:2(27-36)Online publication date: 28-Oct-2013
https://dl.acm.org/doi/10.1145/2578856.2508171
Allende EFabry JTanter ÉHosking AEugster PBolz C(2013)Cast insertion strategies for gradually-typed objectsProceedings of the 9th symposium on Dynamic languages10.1145/2508168.2508171(27-36)Online publication date: 28-Oct-2013
https://dl.acm.org/doi/10.1145/2508168.2508171
Wehr SThiemann P(2011)JavaGIACM Transactions on Programming Languages and Systems (TOPLAS)10.1145/1985342.198534333:4(1-83)Online publication date: 1-Jul-2011
https://dl.acm.org/doi/10.1145/1985342.1985343

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