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1ML – core and modules united (F-ing first-class modules)

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Andreas RossbergAuthors Info & Claims

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

Pages 35 - 47

https://doi.org/10.1145/2784731.2784738

Published: 29 August 2015 Publication History

Abstract

ML is two languages in one: there is the core, with types and expressions, and there are modules, with signatures, structures and functors. Modules form a separate, higher-order functional language on top of the core. There are both practical and technical reasons for this stratification; yet, it creates substantial duplication in syntax and semantics, and it reduces expressiveness. For example, selecting a module cannot be made a dynamic decision. Language extensions allowing modules to be packaged up as first-class values have been proposed and implemented in different variations. However, they remedy expressiveness only to some extent, are syntactically cumbersome, and do not alleviate redundancy. We propose a redesign of ML in which modules are truly first-class values, and core and module layer are unified into one language. In this "1ML", functions, functors, and even type constructors are one and the same construct; likewise, no distinction is made between structures, records, or tuples. Or viewed the other way round, everything is just ("a mode of use of") modules. Yet, 1ML does not require dependent types, and its type structure is expressible in terms of plain System Fω, in a minor variation of our F-ing modules approach. We introduce both an explicitly typed version of 1ML, and an extension with Damas/Milner-style implicit quantification. Type inference for this language is not complete, but, we argue, not substantially worse than for Standard ML. An alternative view is that 1ML is a user-friendly surface syntax for System Fω that allows combining term and type abstraction in a more compositional manner than the bare calculus.

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Cited By

Wu DFluet M(2025)A Preliminary Type- and Control-Flow Analysis for System F$$_\omega $$Trends in Functional Programming10.1007/978-3-031-74558-4_8(160-194)Online publication date: 10-Jan-2025
https://doi.org/10.1007/978-3-031-74558-4_8
Eisenberg RDuboc GWeirich SLee D(2021)An existential crisis resolved: type inference for first-class existential typesProceedings of the ACM on Programming Languages10.1145/34735695:ICFP(1-29)Online publication date: 19-Aug-2021
https://dl.acm.org/doi/10.1145/3473569
Parreaux L(2020)The simple essence of algebraic subtyping: principal type inference with subtyping made easy (functional pearl)Proceedings of the ACM on Programming Languages10.1145/34090064:ICFP(1-28)Online publication date: 3-Aug-2020
https://dl.acm.org/doi/10.1145/3409006
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Index Terms

1ML – core and modules united (F-ing first-class modules)
1. Software and its engineering
  1. Software notations and tools
    1. Formal language definitions
    2. General programming languages
      1. Language features
2. Theory of computation
  1. Formal languages and automata theory
  2. Semantics and reasoning
    1. Program constructs

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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

Wu DFluet M(2025)A Preliminary Type- and Control-Flow Analysis for System F$$_\omega $$Trends in Functional Programming10.1007/978-3-031-74558-4_8(160-194)Online publication date: 10-Jan-2025
https://doi.org/10.1007/978-3-031-74558-4_8
Eisenberg RDuboc GWeirich SLee D(2021)An existential crisis resolved: type inference for first-class existential typesProceedings of the ACM on Programming Languages10.1145/34735695:ICFP(1-29)Online publication date: 19-Aug-2021
https://dl.acm.org/doi/10.1145/3473569
Parreaux L(2020)The simple essence of algebraic subtyping: principal type inference with subtyping made easy (functional pearl)Proceedings of the ACM on Programming Languages10.1145/34090064:ICFP(1-28)Online publication date: 3-Aug-2020
https://dl.acm.org/doi/10.1145/3409006
Downen PSullivan ZAriola ZPeyton Jones S(2019)Codata in ActionProgramming Languages and Systems10.1007/978-3-030-17184-1_5(119-146)Online publication date: 6-Apr-2019
https://doi.org/10.1007/978-3-030-17184-1_5
Amin NRompf T(2017)Type soundness proofs with definitional interpretersACM SIGPLAN Notices10.1145/3093333.300986652:1(666-679)Online publication date: 1-Jan-2017
https://dl.acm.org/doi/10.1145/3093333.3009866
Amin NRompf TCastagna GGordon A(2017)Type soundness proofs with definitional interpretersProceedings of the 44th ACM SIGPLAN Symposium on Principles of Programming Languages10.1145/3009837.3009866(666-679)Online publication date: 1-Jan-2017
https://dl.acm.org/doi/10.1145/3009837.3009866
Rompf TAmin N(2016)Type soundness for dependent object types (DOT)ACM SIGPLAN Notices10.1145/3022671.298400851:10(624-641)Online publication date: 19-Oct-2016
https://dl.acm.org/doi/10.1145/3022671.2984008
Rompf TAmin NVisser ESmaragdakis Y(2016)Type soundness for dependent object types (DOT)Proceedings of the 2016 ACM SIGPLAN International Conference on Object-Oriented Programming, Systems, Languages, and Applications10.1145/2983990.2984008(624-641)Online publication date: 19-Oct-2016
https://dl.acm.org/doi/10.1145/2983990.2984008
Inoue JKiselyov OKameyama YErwig MRompf T(2016)Staging beyond terms: prospects and challengesProceedings of the 2016 ACM SIGPLAN Workshop on Partial Evaluation and Program Manipulation10.1145/2847538.2847548(103-108)Online publication date: 11-Jan-2016
https://dl.acm.org/doi/10.1145/2847538.2847548
Rossberg A(2016)1ML with Special EffectsA List of Successes That Can Change the World10.1007/978-3-319-30936-1_18(336-355)Online publication date: 25-Mar-2016
https://doi.org/10.1007/978-3-319-30936-1_18
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