September 2024 - Haskell-Cafe

Best way to implement "scoped exceptions"?
by Tom Ellis 28 May '25

28 May '25

I'd like to implement "scoped exceptions"[1], that is, a combinator of type withScopedException :: ((forall a. e -> IO a) -> IO r) -> IO (Either e r) so I can use exceptions in a convenient way, without having to set up fragile "action at a distance" based on the type of the thing I'm throwing and catching, for example: scopedExceptionExample :: IO (Either String (Either Int Void)) scopedExceptionExample = do withScopedException $ \throw1 -> withScopedException $ \throw2 -> if (1 :: Int) < 0 then throw1 "Hello" else throw2 1234 -- ghci> scopedExceptionExample -- Right (Left 1234) Here's a hacky way of doing it, based on tagging each exception with a unique value, and then filtering when handling: data MyException where MyException :: e -> Data.Unique.Unique -> MyException instance Show MyException where show _ = "<MyException>" instance Exception MyException withScopedException :: ((forall a. e -> IO a) -> IO r) -> IO (Either e r) wiathScopedException f = do fresh <- Data.Unique.newUnique flip tryJust (f (\e -> throwIO (MyException e fresh))) $ \case MyException e tag -> -- unsafeCoerce is very unpleasant if tag == fresh then Just (unsafeCoerce e) else Nothing This is the approach taken by the effectful library[2]. But is there a better way? Can I persuade GHC's RTS to work like this directly? Tom [1] I don't know if these already have a name [2] https://hackage.haskell.org/package/effectful-core-2.2.1.0/docs/src/Effectf…

5 7

Journal of Functional Programming - Call for PhD Abstracts
by Graham Hutton 04 Nov '24

04 Nov '24

Dear all, If you or one of your students recently completed a PhD (or Habilitation) in the area of functional programming, please submit the dissertation abstract for publication in JFP: simple process, no refereeing, open access, 200+ published to date, deadline 31st May 2024. Please share! Best wishes, Graham Hutton ============================================================ CALL FOR PHD ABSTRACTS Journal of Functional Programming Deadline: 31st May 2024 http://tinyurl.com/jfp-phd-abstracts ============================================================ PREAMBLE: Many students complete PhDs in functional programming each year. As a service to the community, twice per year the Journal of Functional Programming publishes the abstracts from PhD dissertations completed during the previous year. The abstracts are made freely available on the JFP website, i.e. not behind any paywall. They do not require any transfer of copyright, merely a license from the author. A dissertation is eligible for inclusion if parts of it have or could have appeared in JFP, that is, if it is in the general area of functional programming. The abstracts are not reviewed. Please submit dissertation abstracts according to the instructions below. We welcome submissions from both the student and the advisor/supervisor although we encourage them to coordinate. Habilitation dissertations are also eligible for inclusion. ============================================================ SUBMISSION: Please submit the following information to Graham Hutton <graham.hutton(a)nottingham.ac.uk> by 31st May 2024. o Dissertation title: (including any subtitle) o Student: (full name) o Awarding institution: (full name and country) o Date of award: (month and year; depending on the institution, this may be the date of the viva, corrections being approved, graduation ceremony, or otherwise) o Advisor/supervisor: (full names) o Dissertation URL: (please provide a permanently accessible link to the dissertation if you have one, such as to an institutional repository or other public archive; links to personal web pages should be considered a last resort) o Dissertation abstract: (plain text, maximum 350 words; you may use \emph{...} for emphasis, but we prefer no other markup or formatting; if your original abstract exceeds the word limit, please submit an abridged version within the limit) Please do not submit a copy of the dissertation itself, as this is not required. JFP reserves the right to decline to publish abstracts that are not deemed appropriate. ============================================================ PHD ABSTRACT EDITOR: Graham Hutton School of Computer Science University of Nottingham Nottingham NG8 1BB United Kingdom ============================================================ 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.

1 1

39th Agda Implementor's Meeting (AIM XXXIX) 25-30 Nov 2024 in Gothenburg
by Andreas Abel 21 Sep '24

21 Sep '24

---------------------------------------------------------------------- Agda Implementors' Meeting XXXIX Call for participation https://wiki.portal.chalmers.se/agda/Main/AIMXXXIX ---------------------------------------------------------------------- The 39th Agda Implementors' Meeting will take place in Gothenburg, Sweden, from Monday 25th to Saturday 30th November 2024. (This is our 20th anniversary of Agda meetings, the first took place in Fall 2004 in Gothenburg.) The meeting will consist of: * Presentations concerning theory, implementation, and use cases of Agda and other Agda-like languages. * Discussions around issues related to the Agda language. * Plenty of time to work in, on, under or around Agda, in collaboration with other participants. * A special session dedicated to the 20th anniversary of AIM. Attendance is free of charge, but a registration is warranted until 31st October 2024 (soft deadline). For information how to register check out https://wiki.portal.chalmers.se/agda/Main/AIMXXXIX Looking forward to seeing you in there! Andreas (on behalf of the AIM XXXIX organizing committee) -- Andreas Abel <>< Du bist der geliebte Mensch. Department of Computer Science and Engineering Chalmers and Gothenburg University, Sweden andreas.abel(a)gu.se http://www.cse.chalmers.se/~abela/

1 0

PhD position at KU Leuven
by Tom Schrijvers 17 Sep '24

17 Sep '24

KU Leuven invites applications for a PhD position in Prof. Tom Schrijvers' research team, exploring the interaction between multi-stage programming and computational effects. Ideal candidates hold a Master's in Computer Science, have a strong academic record, and a passion for programming languages like Haskell, type systems, and functional programming. We offer a 4-year scholarship, a dynamic research environment, and opportunities for international collaboration. Join us to push the boundaries of programming language theory! For more information see: https://www.kuleuven.be/personeel/jobsite/jobs/60384347?hl=nl&lang=nl

1 0

Call for Volunteers - Security Response Team
by Jose Calderon 05 Sep '24

05 Sep '24

The Security Response Team (SRT) is formally calling for applications to join the SRT. People from the Haskell community with information security experience are encouraged to apply. This is an opportunity to have a large impact on the practice of Haskell programming going forward. Since its inception, the SRT has had an outsized impact on the Haskell Ecosystem. I can say with confidence that the group conducts its business in an extremely professional and disciplined manner. If you have an interest in helping the team continue its mission, please apply! ## Security Response Team responsibilities The general responsibilities of the SRT are: - Manage the Haskell Security Advisory Database, on behalf of the Haskell community and the Haskell Foundation. - Triage and assess incoming security reports or proposed/candidate security advisories. - Assist reporters to determine CVSS scores and CWE values for confirmed security issues. - Communicate with package maintainers and the community to promote the timely resolution of reported security issues. - Ensure the security advisory data are useful for downstream security tooling. (Development of downstream tooling is not an SRT responsibility, but engaging with the developers is) - Report quarterly on the activities of the SRT and statistics/trends in new security issues. ## How can you help? - You can apply - If you don't want to apply but know someone who would be great, encourage them to apply. - Volunteers should have experience in one or more of the following areas: - web application security - information security incident response - vulnerability research and analysis - penetration testing - cryptography - authentication and identity management - governance, risk management and compliance (GRC) - secure application development - algorithms, data structures, and their role in DoS attacks - related disciplines ## Who is involved? The current membership of the SRT is: - Fraser Tweedale - Gautier Di Folco - Mihai Maruseac - Tristan de Cacqueray The team is hoping to gain 2-3 new members via this call for volunteers. ## How to apply Email `Fraser Tweedale <frase%2Bhasksec(a)frase.id.au>` with subject "Haskell SRT Application". Include a brief overview of your background in security and the specific topics (e.g. from the list above) with which you have experience. ## Deadline Please submit your applications by end of day September 30th, 2024.

1 0

[TFP 2025 Call for Papers] 25th International Symposium on Trends in Functional Programming (Oxford, UK)
by Peter Achten 04 Sep '24

04 Sep '24

# TFP 2025 - Call for Papers (trendsfp.github.io) ## 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) 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

1 0

Call for Participation - Haskell Bug Interviews
by Leonhard Applis 02 Sep '24

02 Sep '24

Dear Haskell Mailing List, we are looking for participants for a ~30 minute interview on bugs, debugging and bug-classification in Haskell. There is a big body of literature on this for e.g. Java, but Haskell might has its own challenges (or hidden similarities), and we hope to map out valuable research that helps practitioners. Your opinion really matters, and I want to encourage anyone to reach out to us even if you don't feel "experienced enough". We don't have a measure for what a real Haskell programmer must do, and if you are coming from a different paradigm and background your insights are very valuable too. The only requirement is to use Haskell regularly enough to encounter and fix bugs, preferably in contact with other humans. This research is currently conducted at the TU Delft and underlies its Data Protection and Ethics standards. Participants from Industry are particularly encouraged and it is possible to redact the transcript post-interview to ensure only things are shared you are comfortable sharing. We will not share interviews or transcripts - only excerpts anonymized and gathered in a codebook. Looking forward for all your Bugs! Best Leonhard Applis (L.H.Applis(a)tu-delft.nl , Leonhard.Applis(a)Protonmail.com) Razvan Nistor (rnistor(a)protonmail.com)

1 0

NFData instance for ForeignPtr
by Vanessa McHale 02 Sep '24

02 Sep '24

I see that deepseq/base have NFData instances for Ptr but not ForeignPtr. Is there a reason there can be no such instance? Cheers, Vanessa McHale

1 0