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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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GHC Steering Committee Call for Nominations
by Simon Marlow 16 Oct '25

16 Oct '25

Dear Haskellers, The GHC Steering Committee is seeking nominations for new members. *To nominate yourself *please send an email to Simon Marlow <marlowsd(a)gmail.com> <marlowsd(a)gmail.com>, briefly summarising your background and relevant experience. See below for details on what committee membership involves, and what kind of experience would be useful. DEADLINE: 6 November 2025 *What's the GHC steering committee?* The committee scrutinizes, debates and eventually decides to accept or reject proposals to change the language or major features supported by GHC. Our processes are described in the GitHub repository <https://github.com/ghc-proposals/ghc-proposals> where proposals are submitted. In particular, please have a look at the Committee bylaws <https://github.com/ghc-proposals/ghc-proposals/blob/master/committee.rst>. *Who are we looking for?* We are looking for members who have the ability to: - understand GHC proposals (e.g. for new language extensions), - find holes and missing corner cases in the specifications, - foresee the interaction with other language or compiler features, - comment constructively and improve proposals through engagement with others, - judge the cost/benefit ratio of changes, and - come to a justifiable conclusion. Ideally, committee members should: - have substantial experience of writing or teaching Haskell; - have a track record of active contributions to the Haskell community; or - have expertise in language design and implementation, in either Haskell or related languages. It is our aim that this committee be diverse; by representing different viewpoints, we will make decisions that benefit larger segments of our community. Even if you are uncertain whether your background qualifies you for the role, you are warmly encouraged to apply. The committee's work requires a small, but non-trivial amount of time, especially when you are assigned a proposal for shepherding. We estimate the workload to be around 2 hours per week, and our process works best if members usually respond to technical emails within 1-2 weeks (within days is even better). Please keep that in mind if your email inbox is already overflowing. Committee members serve for 3 years, but are free to re-nominate themselves when their 3-year term expires. Self-nominations are the norm. You can nominate someone else, but please obtain their explicit consent to do so. (We don't want to choose someone who turns out to be unable to serve.) *What happens after nominations?* In accordance with our Committee bylaws <https://github.com/ghc-proposals/ghc-proposals/blob/master/committee.rst>, the committee deliberates nominations *in private* before communicating the decision. The committee doesn't have a fixed size, although we like to have a minimum of 9 members. There are currently two members rotating off, but as the committee currently has 10 members, we will be looking to appoint at least one but possibly (hopefully!) more. On behalf of the committee, Simon Marlow

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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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[TFP 2026] Call for Papers for the 27th International Symposium on Trends in Functional Programming, Odense, Denmark, January 2026
by Peter Achten 22 Sep '25

22 Sep '25

# TFP 2026 -- Call for Papers (trendsfp.github.io) ## Important Dates * Submission deadline (pre-symposium, full papers): Thu 13th Nov 2025 (AOE) * Notification (pre-symposium, full papers): Thu 11th Dec 2025 * Submission deadline (pre-symposium draft papers): Thu 11th Dec 2025 (AOE) * Notification (pre-symposium draft papers): Fri 19th Dec 2025 * Submission deadline (post-symposium review): Thu 5th Mar 2026 (AOE) * Notification (post-symposium submissions): Thu 16th Apr 2026 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 Southern Denmark, in Odense, Denmark. 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, Casper Bach. ## 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 HotCRP: https://tfp26.hotcrp.com/ 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). See below for more details. Submission is single-blind. Submissions are welcome from PC members (except the chair). Accepted papers from the pre-symposium and post-symposium formal review will appear in a formal proceedings, published by Springer. 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…) ### 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. ## Organizing Committee | Casper Bach | University of Southern Denmark, DK | Programme Chair | | Jeremy Gibbons | University of Oxford | General Chair | | Peter Achten | Radboud University Nijmegen, NL | Publicity Chair | | Marco T. Morazán | Seton Hall University, US | Steering Committee Chair | ## Programme Committee | Alex Gerdes | University of Gothenburg and Chalmers, SE | | Andrew Tolmach | Portland State University, US | | Ben Greenman | University of Utah, US | | Bruno Oliveira | University of Hong Kong, HK | | Cas van der Rest | Shielded Technologies, NL | | Cristina Matache | University of Edinburgh, UK | | Di Wang | Peking University, CN | | Dylan McDermott | University of Oxford, UK | | Eric Van Wyk | University of Minnesota, US | | Jan de Muijnck-Hughe | Strathclyde, UK | | Jeremy Yallop | University of Cambridge, UK | | Jesper Cockx | Delft University of Technology, NL | | Jules Jacobs | Cornell University, US | | Mart Lubbers | Radboud University, NL | | Matthew Lutze | Aarhus University, DK | | Max S. New | University of Michigan, US | | Nicolas Wu | Imperial College London, UK | | Patrick Bahr | IT University of Copenhagen, DK |

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