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[ANNOUNCE] Ajla 0.3.0 with formal verification using Z3
by Mikulas Patocka 28 Oct '25

28 Oct '25

Hi I announce a new release of a purely functional programming language Ajla 0.3.0 - https://www.ajla-lang.cz/ It has a new feature - the capability to formally verify programs using the Z3 library - see https://www.ajla-lang.cz/tutorial.html#verifying_ajla_programs_with_z3 Mikulas

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GHC 9.12.3 status update
by Zubin Duggal 28 Oct '25

28 Oct '25

Hi all, I'm currently working on the final set of backports for GHC 9.12.3-rc2. This has been delayed due to #26166 making bootstrapping GHC impossible on the new macOS release. I am currently in the process of backporting the fix for this ticket (among a few other patches) to GHC 9.12. I expect to have rc2 out in the next few days, by the end of this week. Cheers, Zubin. #26166: https://gitlab.haskell.org/ghc/ghc/-/issues/26166

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Adding `reverse` and `sortBy` to `Traversable`
by Keith 27 Oct '25

27 Oct '25

Folks[1] have known for a long time that `reverse` and `sortBy` can both be implemented in terms of `mapAccumL`. Would it make sense to add those to `Data.Traversable` as functions or methods? [1] For example, Will Fancher wrote about it in 2017. --- Sent from my phone with K-9 Mail.

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TFPiE 2026, second call for submissions
by Mart Lubbers 27 Oct '25

27 Oct '25

TFPIE 2026 Call for papers https://wiki.tfpie.science.ru.nl/TFPIE2026 (January 26th 2026, Odense, Denmark, co-located with TFP 2026 at University of Southern Denmark) TFPIE 2026 welcomes submissions describing techniques used in the classroom, tools used in and/or developed for the classroom and any creative use of functional programming (FP) to aid education in or outside Computer Science. Topics of interest include, but are not limited to: - FP and beginning CS students - FP and Computational Thinking - FP and Artificial Intelligence - FP in Robotics - FP and Music - Advanced FP for undergraduates - FP in graduate education - Engaging students in research using FP - FP in Programming Languages - FP in the high school curriculum - FP as a stepping stone to other CS topics - FP and Philosophy - The pedagogy of teaching FP - FP and e-learning: MOOCs, automated assessment etc. - Best Lectures - more details below In addition to papers, we are requesting best lecture presentations. What's your best lecture topic in an FP related course? Do you have a fun way to present FP concepts to novices or perhaps an especially interesting presentation of a difficult topic? In either case, please consider sharing it. Best lecture topics will be selected for presentation based on a short abstract describing the lecture and its interest to TFPIE attendees. The length of the presentation should be comparable to that of a paper. In addition, the speaker can provide commentary on effectiveness or student feedback. ## Submissions Potential presenters are invited to submit an extended abstract (4-6 pages) or a draft paper (up to 20 pages) in EPTCS style. The authors of accepted presentations will have their preprints and their slides made available on the workshop's website. Papers and abstracts can be submitted via easychair at the following link: https://easychair.org/my/conference?conf=tfpie26 After the workshop, presenters are invited to submit (a revised version of) their article for the formal review. The PC will select the best articles for publication in the Electronic Proceedings in Theoretical Computer Science (EPTCS). Articles rejected for presentation and extended abstracts will not be formally reviewed by the PC. ## Important Dates Submission deadline: December 26th 2025, Anywhere on Earth Notification: by December 30th 2025 (Note: submissions will be evaluated on a rolling basis, so earlier submissions will receive an earlier response) TFPIE Registration Deadline: TBA Workshop: January 26th 2026 Submission for formal review: April 22nd 2026, Anywhere on Earth Notification of full article: May 27th 2026 Camera ready: June 24th 2026 ## Program Committee Mart Lubbers, Radboud University, Nijmegen, Netherlands (PC Chair) Tim Steenvoorden, Open Universitei, Heerlen, Netherlands Marco T. Morazán, Seton Hall University, South Orange, NJ, USA Guannan Wei, Tufts University, Medford, MA, USA Marcos Viera, Universidad de la República, Montevideo, Uruguay Johannes Åman Pohjola, Chalmers University of Technology, Götenburg, Sweden ## Registration information See https://wiki.tfpie.science.ru.nl/TFPIE2026 for updated information. Registration and attendance are mandatory for at least one author of every paper that is presented at the workshop. Only papers that have been presented at TFPIE may be submitted to the post-reviewing process.

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POPL 2026 Call for Student Volunteers
by Ningning Xie 14 Oct '25

14 Oct '25

*Call for Student Volunteers* Sign up to be a Student Volunteer and help us make POPL 2026 a unique experience for all attendants! POPL 2026 is pleased to offer a number of opportunities for student volunteers, who are vital to the efficient operation and continued success of the conference each year. The student volunteer program is a chance for students from around the world to participate in the conferences whilst assisting us in preparing and running the event. The Student Volunteer Program helps more students attend the POPL conference by covering registration to the conferences, tutorials, workshops, and all associated events (but not travel or lodging expenses). In exchange for a fixed number of work hours (around 18) helping with the conference organization, you will be able to closely interact with researchers, mentors, and other students at POPL 2026. We are looking forward to seeing you in the SV team! *Eligibility* Applicants can be undergraduate, Master’s, Ph.D. full- or part-time students, of computer science or related fields, with or without previous experience as volunteers. Everyone is encouraged to apply! *Duration* Applicants must be available for at least four (4) full days between the 11th and 17th of January 2026, and will be expected to provide at least 18 hours of volunteering work in that time. Volunteers will also be expected to be available for some amount of pre-conference discussion and training if necessary. *Compensation* Every student volunteer will receive: - A complimentary conference registration, offering access to all open sessions (i.e., parallel paper presentations, demonstrations, and workshops) and conference proceedings. - Free lunches and refreshments during breaks. - Student volunteer garments. Please note that Student Volunteers are responsible for their own travel and accommodation arrangements. However, Student Volunteers can apply for extra funding from SIGPLAN PAC funding or PLMW when eligible. You can send questions about student volunteering to Aurèle Barrière ( aurele.barriere(a)epfl.ch) and Stephen Mell (sm1(a)cis.upenn.edu) *Applications* To apply, fill out the form on this link, before November 10th: https://forms.gle/YiMy1PXVF6QWggsb8 <https://urldefense.com/v3/__https://forms.gle/YiMy1PXVF6QWggsb8__;!!IBzWLUs…> . The form is very short and won’t take more than 5 minutes to complete. We will NOT evaluate the applications in a first come first serve order. *Deadline for submission: November 10th 2025, AoE.*

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Re: fplangc
by Anthony Clayden 13 Oct '25

13 Oct '25

Hi Asher, good question! I've been waiting in case 'former members' might respond. You're presumably aware of Wadler's 'Proposal: Overloading in Haskell' 1988 that originally appeared on fplangc. Link from https://homepages.inf.ed.ac.uk/wadler/topics/type-classes.html I've tried the wayback machine for fplangc(a)cs.ucl.ac.uk, but got nothing useful. The repository I dig through is on wayback (various save dates) http://web.archive.org/web/20151208175102/http://code.haskell.org/~dons/has… The earliest 1990 threads are clearly continuations from somewhere. If ~dons (Don Stewart) kept archives of those, they're defeating my google-fu. But hmmm, wayback is unreliable: it can peremptorily just delete stuff if it gets a copyright strike, or for no apparent reason. The Haskell developers (for Hugs and ghc) generally published papers with the motivations for their innovations. What additional to that thinking do you hope to find in the mailing lists? Good luck! AntC

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PEPM 2026: Second Call for Papers
by Ningning Xie 08 Oct '25

08 Oct '25

CALL FOR PAPERS The 2026 ACM SIGPLAN Workshop on Partial Evaluation and Program Manipulation https://popl26.sigplan.org/home/pepm-2026 # Important Dates, AoE, UTC-12h Paper due Fri 25 Oct 2025 Notification Fri 28 Nov 2025 Workshop Tue 13 Jan 2026 # About The ACM SIGPLAN Workshop on Partial Evaluation and Program Manipulation (PEPM) has a history going back to 1991 and has been held in conjunction with POPL every year since 2006. The origin of PEPM is in the discoveries of practically useful automated techniques for evaluating programs with only partial input. Over time, PEPM has broadened its scope to include a variety of research areas centered around semantics-based program manipulation — the systematic exploitation of treating programs not only as subject to black-box execution, but also as data structures that can be generated, analyzed, and transformed while establishing or maintaining important semantic properties. # Scope Topics of interest for PEPM 2026 include, but are not limited to: * Program and model manipulation techniques such as: supercompilation, partial evaluation, fusion, on-the-fly program adaptation, active libraries, program inversion, slicing, symbolic execution, refactoring, decompilation, and obfuscation. * Techniques that treat programs/models as data objects including metaprogramming, generative programming, embedded domain-specific languages, program synthesis by sketching and inductive programming, staged computation, and model-driven program generation and transformation. * Program analysis techniques that are used to drive program/model manipulation such as: abstract interpretation, termination checking, binding-time analysis, constraint solving, type systems, automated testing and test case generation. * Application of the above techniques including case studies of program manipulation in real-world (industrial, open-source) projects and software development processes, descriptions of robust tools capable of effectively handling realistic applications, benchmarking. Examples of application domains include legacy program understanding and transformation, DSL implementations, visual languages and end-user programming, scientific computing, middleware frameworks and infrastructure needed for distributed and web-based applications, embedded and resource-limited computation, and security. * Cross-fertilization with other fields, such as semantics based and machine-learning based program synthesis and program optimisation, and modeling, analysis, and transformation techniques for distributed and concurrent protocols and programs, such as session types, linear types, and contract specifications. This list of categories is not exhaustive, and we encourage submissions describing new theories and applications related to semantics-based program manipulation in general. If you have a question as to whether a potential submission is within the scope of the workshop, please contact the programme co-chairs, Yukiyoshi Kameyama (kameyama at acm.org) and Ningning Xie (ningningxie at cs.toronto.edu) # Submission Categories and Guidelines Three kinds of submissions will be accepted: 1. Regular Research Papers should describe new results, and will be judged on originality, correctness, significance, and clarity. Regular research papers must not exceed 12 pages. 2. Short Papers may include tool demonstrations and presentations of exciting if not fully polished research, and of interesting academic, industrial, and open-source applications that are new or unfamiliar. Short papers must not exceed 6 pages. 3. Talk Proposals may propose lectures about topics of interest for PEPM, existing work representing relevant contributions, or promising contributions that are not mature enough to be proposed as papers of the other categories. Talk Proposals must not exceed 2 pages. References and appendices are not included in page limits. Appendices may not necessarily be read by reviewers. All the submissions should be typeset using the two-column ‘sigplan’ sub-format of the new ‘acmart’ format available at: https://sigplan.org/Resources/Author/ and submitted electronically via HotCRP: https://pepm26.hotcrp.com Reviewing will be single-blind. Submissions are welcome from PC members (except the two co-chairs). Accepted regular research papers will appear in formal proceedings published by ACM, and be included in the ACM Digital Library. Accepted short papers do not constitute formal publications and will not appear in the proceedings. At least one author of each accepted contribution must attend the workshop (physically or virtually) to present the work. In the case of tool demonstration papers, a live demonstration of the described tool is expected. ## Program co-chairs Yukiyoshi Kameyama, University of Tsukuba, Japan Ningning Xie, University of Toronto, Canada ## PC members Kenichi Asai, Ochanomizu University Robert Atkey, University of Strathclyde Stephanie Balzer, CMU William J. Bowman, University of British Columbia Paul Downen, University of Massachusetts, Lowell Sebastian Erdweg, JGU Mainz Robert Glück, University of Copenhagen Zhenjiang Hu, Peking University Yusuke Izawa, Tokyo Metropolitan University Naoki Kobayashi, University of Tokyo Geoffrey Mainland, Drexel University Keisuke Nakano, Tohoku University Lionel Parreaux, Hong Kong University of Science and Technology Morten Rhiger, Roskilde University Tom Schrijvers, KU Leuven Guannan Wei, Tufts University Leo White, Jane Street

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package takeover request: bumper
by Artem Pelenitsyn 07 Oct '25

07 Oct '25

Hey all, I'm interested in taking over https://hackage.haskell.org/package/bumper The package has not seen updates in a long while, so I assume it's fine with the previous maintainer but I CC the email listed in the maintainer field of the package description. -- Best, Artem

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fplangc
by Asher Olsen 06 Oct '25

06 Oct '25

As an enthusiast of programming language history, I think it would be valuable to make archives of the original Haskell design mailing list FPLANGC, if they exist anywhere, publically available online. Such accessible archives exist for Common Lisp and Scheme (< http://cl-su-ai.lisp.se/threads.html> and < https://groups.csail.mit.edu/mac/projects/scheme/rrrs-archive.html>). Would that be possible (addressing any former members of that list who might be reading this)? Thanks, Asher Olsen

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TFPIE 2026 - Call for Papers
by Mart Lubbers 29 Sep '25

29 Sep '25

TFPIE 2026 Call for papers https://wiki.tfpie.science.ru.nl/TFPIE2026 (January 26th 2026, Odense, Denmark, co-located with TFP 2026 at University of Southern Denmark) TFPIE 2026 welcomes submissions describing techniques used in the classroom, tools used in and/or developed for the classroom and any creative use of functional programming (FP) to aid education in or outside Computer Science. Topics of interest include, but are not limited to: - FP and beginning CS students - FP and Computational Thinking - FP and Artificial Intelligence - FP in Robotics - FP and Music - Advanced FP for undergraduates - FP in graduate education - Engaging students in research using FP - FP in Programming Languages - FP in the high school curriculum - FP as a stepping stone to other CS topics - FP and Philosophy - The pedagogy of teaching FP - FP and e-learning: MOOCs, automated assessment etc. - Best Lectures - more details below In addition to papers, we are requesting best lecture presentations. What's your best lecture topic in an FP related course? Do you have a fun way to present FP concepts to novices or perhaps an especially interesting presentation of a difficult topic? In either case, please consider sharing it. Best lecture topics will be selected for presentation based on a short abstract describing the lecture and its interest to TFPIE attendees. The length of the presentation should be comparable to that of a paper. In addition, the speaker can provide commentary on effectiveness or student feedback. ## Submissions Potential presenters are invited to submit an extended abstract (4-6 pages) or a draft paper (up to 20 pages) in EPTCS style. The authors of accepted presentations will have their preprints and their slides made available on the workshop's website. Papers and abstracts can be submitted via easychair at the following link: https://easychair.org/conferences/?conf=tfpie2026 After the workshop, presenters are invited to submit (a revised version of) their article for the formal review. The PC will select the best articles for publication in the Electronic Proceedings in Theoretical Computer Science (EPTCS). Articles rejected for presentation and extended abstracts will not be formally reviewed by the PC. ## Important Dates Submission deadline: December 26th 2023, Anywhere on Earth Notification: by December 30th 2023 (Note: submissions will be evaluated on a rolling basis, so earlier submissions will receive an earlier response) TFPIE Registration Deadline: Workshop: January 26th 2026 Submission for formal review: April 22nd 2026, Anywhere on Earth Notification of full article: May 27th 2026 Camera ready: June 24th 202 ## Program Committee Mart Lubbers, Radboud University, Nijmegen, Netherlands (PC Chair) Tim Steenvoorden, Open Universitei, Heerlen, Netherlands Marco T. Morazán, Seton Hall University, South Orange, NJ, USA Guannan Wei, Tufts University, Medford, MA, USA Marcos Viera, Universidad de la República, Montevideo, Uruguay Johannes Åman Pohjola, Chalmers University of Technology, Götenburg, Sweden ## Registration information See https://wiki.tfpie.science.ru.nl/TFPIE2026 for updated information. Registration and attendance are mandatory for at least one author of every paper that is presented at the workshop. Only papers that have been presented at TFPIE may be submitted to the post-reviewing process.

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