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10 PhD studentships in Nottingham
by Graham Hutton 03 Dec '24

03 Dec '24

Dear all, The School of Computer Science at the University of Nottingham in the UK is seeking applications for 10 fully-funded PhD studentships: https://tinyurl.com/ten-phds-2025 Applicants in the area of the Functional Programming Lab (tinyurl.com/fp-notts) are strongly encouraged! If you are interested in applying, please contact a potential supervisor as soon as possible; the application deadline is 6th April 2025: Thorsten Altenkirch - constructive logic, proof assistants, homotopy type theory, category theory, lambda calculus. Ulrik Buchholtz - homotopy type theory, synthetic homotopy theory, proof assistants, constructive mathematics, and related topics. Graham Hutton - not seeking a new student this year, but these notes on the process may be useful: tinyurl.com/phd-notes Nicolai Kraus - not seeking a student through this scheme, but has two other PhD positions available: tinyurl.com/kraus-phds Dan Marsden - category theory, logic, finite model theory, diagrammatic reasoning, foundations of computer science. Best wishes, The FP Lab University of Nottingham +-----------------------------------------------------------+ 10 Fully-Funded PhD Studentships School of Computer Science University of Nottingham, UK https://tinyurl.com/ten-phds-2025 Applications are invited from home and international students for up to 10 fully-funded PhD studentships offered by the School of Computer Science, starting on 1st October 2025. The topics for the studentships are open, but should relate to the interests of one of the School’s research groups: Cyber-Physical Health and Assistive Robotics; Computational Optimisation and Learning Lab; Computer Vision Lab; Cyber Security; Functional Programming; Intelligent Modelling and Analysis; Mixed Reality Lab; Lab for Uncertainty in Data and Decision Making; Visualisation and Computer Graphics; Responsible Digital Futures. The studentships are fully funded for 3.5 years and include a stipend of £19,237 per year and tuition fees. Applicants are normally expected to have a first-class Bachelor or Masters degree or international equivalent, in a related discipline. If you are interested in applying, please contact a potential supervisor as soon as possible, and at least two weeks prior to the closing date. If the supervisor wishes to support your application, they will direct you to make an official application through the MyNottingham system. Closing date for applications: Sunday 6th April 2025 +-----------------------------------------------------------+ This message and any attachment are intended solely for the addressee and may contain confidential information. If you have received this message in error, please contact the sender and delete the email and attachment. Any views or opinions expressed by the author of this email do not necessarily reflect the views of the University of Nottingham. Email communications with the University of Nottingham may be monitored where permitted by law.

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GHC 9.8.4 is now available
by Ben Gamari 02 Dec '24

02 Dec '24

The GHC developers are happy to announce the availability of GHC 9.8.4. Binary distributions, source distributions, and documentation are available on the [release] page. This release is a small release fixing a few issues noted in 9.8.3, including: * Update the `filepath` submodule to avoid a misbehavior of `splitFileName` under Windows. * Update the `unix` submodule to fix a compilation issue on `musl` platforms * Fix a potential source of miscompilation when building large projects on 32-bit platforms * Fix unsound optimisation of `prompt#` uses A full accounting of changes can be found in the [release notes]. As some of the fixed issues do affect correctness users are encouraged to upgrade promptly. We would like to thank Microsoft Azure, GitHub, IOG, the Zw3rk stake pool, Well-Typed, Tweag I/O, Serokell, Equinix, SimSpace, Haskell Foundation, and other anonymous contributors whose on-going financial and in-kind support has facilitated GHC maintenance and release management over the years. Finally, this release would not have been possible without the hundreds of open-source contributors whose work comprise this release. As always, do give this release a try and open a [ticket] if you see anything amiss. Happy compiling! - Ben [release]: https://www.haskell.org/ghc/download_ghc_9_8_4.html [ticket]: https://gitlab.haskell.org/ghc/ghc/-/issues/new [release notes]: https://downloads.haskell.org/~ghc/9.8.4/docs/users_guide/9.8.4-notes.html

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Re: [Haskell-cafe] Files and Modules
by julian getcontented.com.au 02 Dec '24

02 Dec '24

Thanks. Understood about the Linker. I was thinking the linking could be some final phase that was separated out in such a way that would still be compatible with the file system (a HasLinker constraint? ;-) j/k). But to go back to what you were saying, if we had the ability to decouple modules from files it would mean I could set up a notion of dependency between the modules that I have stored in Texts in such a way that I wouldn’t need to repeat code between the Texts when I want to share code as I’m compiling chunks of it. At the moment I try hard to keep the set of common items shared between all the code I have because it makes it simpler to manage and keeps duplication low, and it also means the call to stack that I have only has to include a small set of packages and can be common between all the combined sets of code I have. On 2 Dec 2024, at 11:00 PM, haskell-cafe-request(a)haskell.org wrote: One compromise GHC could make would be abstract the notion of module from the Haskell source (multiple modules per file, no file involved at all), but ultimately as Brandon says, the file system has to get involved for the linker, so the concept of a module needs to remain compatible with the action of writing it as a file.

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Files and Modules
by julian getcontented.com.au 02 Dec '24

02 Dec '24

In a recent project that compiles Haskell source from data (ie of type Text from the module Data.Text), it would be useful to be able to decouple the dependency between GHC’s notion of where modules are and the file system. This doesn’t seem to be programmatically controllable. How tenable is this? Would it be useful for anyone else to have compilation itself be more first class in the language? If I think about languages such as LISP/Racket/Clojure, there’s a certain flexibility there that Haskell lacks, but it’s not apparent why, other than historical reasons? Would this imply changing compiling and linking into a different Monad than IO? At the moment to compile some source that exists in Text, my system has to write a bunch of temp files including the Text that contains the main module, and then put other modules in directories named a certain way, run the compiler across them via some exec command to call GHC or stack externally, then read the resulting executable back off disk to store it in its final destination. It might be useful to be able to do this from within Haskell code directly, partly similarly to how the hint library works. Though, in this case it would almost certainly also require being able to have two versions of GHC loaded at once, which would also imply being able to simultaneously have multiple or different versions of libraries loaded at once, too, and possibly also just from data, ie not from disk. It feels like a massive, massive project at that point, though, like we’d be putting an entire dependency system into a first-class programmable context. I’m still interested in what folks think about these ideas, though, event though we this may never eventuate. Does it seem to anyone else like abstracting the library and module-access capabilities of compilation so that it’s polymorphic over where it gets its data from might be useful? Is this just ridiculous? Does this step into Backpack's territory? From memory, the Haskell report doesn’t specify that modules necessarily need to be tied to the file system, but I think GHC imposes one file per module and that it be one the FS. Julian

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[ANNOUNCE] GHC 9.12.1-rc1 is now available
by Zubin Duggal 29 Nov '24

29 Nov '24

The GHC developers are very pleased to announce the availability of the release candidate for GHC 9.12.1. Binary distributions, source distributions, and documentation are available at [downloads.haskell.org][]. We hope to have this release available via ghcup shortly. GHC 9.12 will bring a number of new features and improvements, including: * The new language extension [OrPatterns] allowing you to combine multiple pattern clauses into one. * The [MultilineStrings] language extension to allow you to more easily write strings spanning multiple lines in your source code. * Improvements to the OverloadedRecordDot extension, allowing the built-in `HasField` class to be used for records with fields of non lifted representations. * The [NamedDefaults] language extension has been introduced allowing you to define defaults for typeclasses other than `Num`. * More deterministic object code output, controlled by the `-fobject-determinism` flag, which improves determinism of builds a lot (though does not fully do so) at the cost of some compiler performance (1-2%). See #12935 for the details * GHC now accepts type syntax in expressions as part of [GHC Proposal #281]. * The WASM backend now has support for TemplateHaskell. * ... and many more A full accounting of changes can be found in the [release notes][]. As always, GHC's release status, including planned future releases, can be found on the GHC Wiki [status][]. We would like to thank GitHub, IOG, the Zw3rk stake pool, Well-Typed, Tweag I/O, Serokell, Equinix, SimSpace, the Haskell Foundation, and other anonymous contributors whose on-going financial and in-kind support has facilitated GHC maintenance and release management over the years. Finally, this release would not have been possible without the hundreds of open-source contributors whose work comprise this release. As always, do give this release a try and open a [ticket][] if you see anything amiss. Cheers, Zubin [release notes]: https://downloads.haskell.org/ghc/9.12.1-rc1/docs/users_guide/9.12.1-notes.… [status]: https://gitlab.haskell.org/ghc/ghc/-/wikis/GHC-status [downloads.haskell.org] https://downloads.haskell.org/ghc/9.12.1-rc1 [ticket]: https://gitlab.haskell.org/ghc/ghc/-/issues/new [OrPatterns]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0522-o… [MultilineStrings]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0569-m… [GHC Proposal #281]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0281-v… [NamedDefaults]: https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0409-e…

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Suggestion for addition to base
by Ivan Perez 23 Nov '24

23 Nov '24

Hi, I have a suggestion of something to add to Control.Arrow. The email address listed here: https://hackage.haskell.org/package/base-4.20.0.1/docs/Control-Arrow.html is libraries(a)haskell.org, which bounces because I'm not subscribed to that mailing list. What's the right mechanism to submit my proposal? Thanks, Ivan

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Re: [Haskell-cafe] attpoarsec and recursive parsing
by Olaf Klinke 23 Nov '24

23 Nov '24

Hi Frederic, Essentially, the '|' character acts like a binary operator in parsing arithmetical expression trees. To that end, the most ergonomic module I know of is provided by parsec [1], which has a port [2] to attoparsec. You have to decide whether the '|' operator should be left- or right- associative. That question vanishes if you decide to re-design your data type as data MaskLocation = MaskLocation Text | MaskLocation'Tmpl Text | MaskLocation'Or (NonEmpty MaskLocation) and use the sepBy1 combinator. Also you should think about whether and how to escape the separator Char inside ordinary MaskLocation strings. Olaf [1] https://hackage.haskell.org/package/parsec-3.1.17.0/docs/Text-ParserCombina… [2] https://hackage.haskell.org/package/attoparsec-expr

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POPL 2025 Call for Participation - Early registration: 20 December
by Ningning Xie 20 Nov '24

20 Nov '24

POPL 2025 -- Call for Participation ** Early registration deadline: 20 December 2024 ** Come and join us for POPL 2025, in January, in Denver, Colorado, the United States. Register here: https://popl25.sigplan.org/attending/registration Location: Curtis Hotel Denver, 1405 Curtis Street, 80202, Denver, Colorado, United States Dates: - Main conference: Wed 22 - Fri 24 January - Workshops, tutorials, co-located events: Sun 19, Mon 20, Tue 21 and Sat 25 January Accepted papers: https://popl25.sigplan.org/track/POPL-2025-popl-research-papers Full details of the conference and co-located events: https://popl25.sigplan.org/ Sponsors: POPL is supported by generous sponsorship from: - Amazon - Jane Street - Google DeepMind - JetBrains - Microsoft - Epic - Google - Ahrefs The 52nd ACM SIGPLAN Symposium on Principles of Programming Languages (POPL 2025) will take place in January in Denver, Colorado, the United States. It's going to be an amazing conference - don't miss it - sign up now! https://popl25.sigplan.org/attending/registration

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Dependent Haskell vs. Explicit Dictionary Application
by Henning Thielemann 20 Nov '24

20 Nov '24

There was an effort to add explicit type class dictionary applications to GHC: https://arxiv.org/abs/1807.11267 Will the new features of Dependent Haskell eventually supersede this approach? The current features in GHC-9.12 do not seem to allow for explicit specification of type class dictionaries.

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[TFP 2025 3rd Call for Papers] 25th International Symposium on Trends in Functional Programming (Oxford, UK)
by Peter Achten 15 Nov '24

15 Nov '24

# TFP 2025 - 3rd Call for Papers (trendsfp.github.io) 26th International Symposium on Trends in Functional Programming 14-16 January 2025, Oxford, UK ## Important Dates Submission deadline (pre-symposium, full papers): Wed 13th Nov 2024 (AOE) Notification (pre-symposium, full papers): Wed 11th Dec 2024 Submission deadline (pre-symposium draft papers): Wed 11th Dec 2024 (AOE) Notification (pre-symposium draft papers): Mon 16th Dec 2024 Submission deadline (post-symposium review): Wed 19th Feb 2025 (AOE) Notification (post-symposium submissions): Wed 26th Mar 2025 The Symposium on Trends in Functional Programming (TFP) is an international forum for researchers with interests in all aspects of functional programming, taking a broad view of current and future trends in the area. It aspires to be a lively environment for presenting the latest research results, and other contributions. This year, TFP will take place in-person at the University of Oxford, UK. It is co-located with the Trends in Functional Programming in Education (TFPiE) workshop, which will take on the day before the main symposium. Please be aware that TFP has several submission deadlines. The first, 13th November, is for authors who wish to have their full paper reviewed prior to the symposium. Papers that are accepted in this way must also be presented at the symposium. The second, 11th December, is for authors who wish to present their work or work-in-progress at the symposium first without submitting to the full review process for publication. These authors can then take into account feedback received at the symposium and submit a full paper for review by the third deadline, 19th February. ## Scope The symposium recognizes that new trends may arise through various routes. As part of the Symposium's focus on trends we therefore identify the following five paper categories. High-quality submissions are solicited in any of these categories: * Research Papers: Leading-edge, previously unpublished research work * Position Papers: On what new trends should or should not be * Project Papers: Descriptions of recently started new projects * Evaluation Papers: What lessons can be drawn from a finished project * Overview Papers: Summarizing work with respect to a trendy subject Papers must be original and not simultaneously submitted for publication to any other forum. They may consider any aspect of functional programming: theoretical, implementation-oriented, or experience-oriented. Applications of functional programming techniques to other languages are also within the scope of the symposium. Topics suitable for the symposium include, but are not limited to: * Functional programming and multicore/manycore computing * Functional programming in the cloud * High performance functional computing * Extra-functional (behavioural) properties of functional programs * Dependently typed functional programming * Validation and verification of functional programs * Debugging and profiling for functional languages * Functional programming in different application areas: security, mobility, telecommunications applications, embedded systems, global computing, grids, etc. * Interoperability with imperative programming languages * Novel memory management techniques * Program analysis and transformation techniques * Empirical performance studies * Abstract/virtual machines and compilers for functional languages * (Embedded) domain specific languages * New implementation strategies * Any new emerging trend in the functional programming area If you are in doubt on whether your paper is within the scope of TFP, please contact the programme chair, Jeremy Gibbons. ## Best Paper Awards TFP awards two prizes for the best papers each year. First, to reward excellent contributions, TFP awards a prize for the best overall paper accepted for the post-conference formal proceedings. Second, each year TFP also awards a prize for the best student paper. TFP traditionally pays special attention to research students, acknowledging that students are almost by definition part of new subject trends. A student paper is one for which the authors state that the paper is mainly the work of students, the students are the paper's first authors, and a student would present the paper. In both cases, it is the PC of TFP that awards the prize. In case the best paper happens to be a student paper, then that paper will receive both prizes. ## Instructions to Authors Submission is via EquinOCS (https://equinocs.springernature.com/service/tfp2025) Please observe that it is temporarily closed while we deal with pre-symposium full paper submissions, it will reopening on 2nd December. Authors of papers have the choice of having their contributions formally reviewed either before or after the Symposium. Further, pre-symposium submissions may either be full (earlier deadline) or draft papers (later deadline). ## Pre-symposium formal review Papers to be formally reviewed before the symposium should be submitted before the early deadline and will receive their reviews and notification of acceptance for both presentation and publication before the symposium. A paper that has been rejected for publication but accepted for presentation may be revised and resubmitted for the post-symposium formal review. ## Post-symposium formal review Draft papers will receive minimal reviews and notification of acceptance for presentation at the symposium. Authors of draft papers will be invited to submit revised papers based on the feedback received at the symposium. A post-symposium refereeing process will then select a subset of these papers for formal publication. ## Paper categories Draft papers and papers submitted for formal review are submitted as extended abstracts (4 to 10 pages in length) or full papers (up to 20 pages). The submission must clearly indicate which category it belongs to: research, position, project, evaluation, or overview paper. It should also indicate which authors are research students, and whether the main author(s) are students. A draft paper for which all authors are students will receive additional feedback by one of the PC members shortly after the symposium has taken place. ## Format Papers must be written in English, and written using the LNCS style. For more information about formatting please consult the Springer LNCS Guidelines web site (https://www.springer.com/gp/computer-science/lncs/conference-proceedings-gu…) ## Organizing Committee Jeremy Gibbons University of Oxford, UK Programme Chair Jason Hemann Seton Hall University, US Conference Chair Peter Achten Radboud University Nijmegen, NL Publicity Chair Marco T. Morazán Seton Hall University, US Steering Committee Chair ## Programme Committee Peter Achten Radboud University Nijmegen, NL Edwin Brady University of St Andrews, UK Laura Castro University of A Coruña, ES Youyou Cong Tokyo Institute of Technology, JP Paul Downen University of Massachusetts Lowell, US João Paulo Fernandes University of Coimbra, PT Ben Greenman University of Utah, US Jurriaan Hage Heriot-Watt University, UK Jason Hemann Seton Hall University, US Zhenjiang Hu Peking University, CN Hans-Wolfgang Loidl Heriot-Watt University, UK Kazutaka Matsuda Tohoku University, JP Zoe Paraskevopoulou Ethereum Foundation, US Alejandro Serrano 47 Degrees, ES Nick Smallbone Chalmers University, SE Alley Stoughton Boston University, US Wouter Swierstra Utrecht University, NL Niki Vazou IMDEA Software Institute, ES Marcos Viera Universidad de la República, UY Viktória Zsók Eötvös Loránd University of Sciences, HU

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