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JOB | Permanent Web Developer (New York)
by James Tobin 16 Apr '18

16 Apr '18

Hello, I'm working with an established financial technology employer that is looking to hire a permanent web developer with significant Java client side experience to join their New York office. Consequently, I had hoped that some members of this mailing list may like to discuss further off-list using "JamesBTobin (at) Gmail (dot) Com". Kind regards, James

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Call for Participation: Summer School on Advanced Functional Programming
by Alejandro Serrano Mena 16 Apr '18

16 Apr '18

# Call for Participation SUMMER SCHOOL ON ADVANCED FUNCTIONAL PROGRAMMING Utrecht, the Netherlands, 27-31 August 2018 http://www.afp.school ## ABOUT The Advanced Functional Programming summer school has been running for more than ten years. We aim to educate aspiring Haskell programmers beyond the basic material covered by many textbooks. The lectures will cover several more advanced topics regarding the theory and practice of Haskell programming, including topics such as: * lambda calculus; * monads and monad transformers; * lazy evaluation; * generalized algebraic data types; * type families and type-level programming; * concurrency and parallelism. The summer school consists of a mix of lectures, labs, and a busy social program. ## LECTURERS Utrecht staff: * Johan Jeuring * Alejandro Serrano Mena * Doaitse Swierstra * Wouter Swierstra Guest lectures: * Manuel Chakravarty * Koen Claessen * Gabriele Keller ## PREREQUISITES We expect students to have a basic familiarity with Haskell already. You should be able to write recursive functions over algebraic data types, such as lists and trees. There is a great deal of material readily available that covers this material. If you’ve already started learning Haskell and are looking to take your functional programming skills to the next level, this is the course for you. ## DATES Registration deadline: 1 August, 2017 School: 27-31 August ## COSTS €1700 - Housing and registration €1500 - Registration only We offer a €1000 discount for students and staff members affiliated with a university. ## SCHOLARSHIPS If you’re struggling to finance your trip to Utrecht, please let us know. We have a limited number of scholarships or discounts available for students that would not be able to attend otherwise, especially for women and under represented minorities. ## FURTHER INFORMATION Further information, including instructions on how to register, is available on our website: http://www.afp.school

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2nd call for papers: Trends in Functional Programming, 11-13 june 2018, Chalmers Campus Johanneberg, Gothenburg
by Peter Achten 16 Apr '18

16 Apr '18

------------------------------------- 2 N D C A L L F O R P A P E R S ------------------------------------- ======== TFP 2018 =========== 19th Symposium on Trends in Functional Programming 11-13 June, 2018 Chalmers Campus Johanneberg, Gothenburg http://www.cse.chalmers.se/~myreen/tfp2018/index.html 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 (see below at scope). Please be aware that TFP uses two distinct rounds of submissions (see below at submission details). TFP 2018 will be the main event of a pair of functional programming events. TFP 2018 will be accompanied by the International Workshop on Trends in Functional Programming in Education (TFPIE), which will take place on June 14. == 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 article categories. High-quality articles are solicited in any of these categories: Research Articles: Leading-edge, previously unpublished research work Position Articles: On what new trends should or should not be Project Articles: Descriptions of recently started new projects Evaluation Articles: What lessons can be drawn from a finished project Overview Articles: Summarizing work with respect to a trendy subject. Articles 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 article is within the scope of TFP, please contact the TFP 2018 program chairs, Michał Pałka and Magnus Myreen. == Best Paper Awards == To reward excellent contributions, TFP awards a prize for the best paper accepted for the formal proceedings. 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 listed as first authors, and a student would present the paper. A prize for the best student paper is awarded each year. In both cases, it is the PC of TFP that awards the prize. In case the best paper happens to be a student paper, that paper will then receive both prizes. == Paper Submissions == We use EasyChair for the refereeing process. The link to the submission page is: https://easychair.org/conferences/?conf=tfp2018 Authors of papers have the choice of having their contributions formally reviewed either before or after the Symposium. == Pre-symposium formal review == Papers to be formally reviewed before the symposium should be submitted before an early deadline and receive their reviews and notification of acceptance for both presentation and publication before the symposium. A paper that has been rejected in this process may still be accepted for presentation at the symposium, but will not be considered 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 receive at the symposium. A post-symposium refereeing process will then select a subset of these articles 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 (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 web site. == Important Dates == Submission (pre-symposium review): March 26, 2018 -- passed -- Submission (draft, post-symposium review): April 26, 2018 -- open -- Notification (pre- and post-symposium review): May 3, 2018 Registration: June 3, 2018 TFP Symposium: June 11-13, 2018 TFPIE Workshop: June 14, 2018 Student papers feedback: June 21, 2018 Submission (post-symposium review): August 14, 2018 Notification (post-symposium review): September 20, 2018 Camera-ready paper (pre- and post-symposium review): November 30, 2018 == Program Committee == Program Co-chairs Michał Pałka, Chalmers University of Technology (SE) Magnus Myreen, Chalmers University of Technology (SE) Program Committee Soichiro Hidaka, Hosei University (JP) Meng Wang, University of Bristol (UK) Sam Tobin-Hochstadt, Indiana University Bloomington (US) Tiark Rompf, Purdue University (US) Patricia Johann, Appalachian State University (US) Neil Sculthorpe, Nottingham Trent University (UK) Andres Löh, Well-Typed LLP (UK) Tarmo Uustalu, Tallinn University of Technology (EE) Cosmin E. Oancea, University of Copenhagen (DK) Mauro Jaskelioff, Universidad Nacional de Rosario (AR) Peter Achten, Radboud University (NL) Dimitrios Vytiniotis, Microsoft Research (UK) Alberto Pardo, Universidad de la República (UY) Natalia Chechina, University of Glasgow (UK) Peter Sestoft, IT University of Copenhagen (DK) Scott Owens, University of Kent (UK)

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WST 2018 - Call for Papers (extended deadline: April 30, 2018)
by Salvador Lucas 14 Apr '18

14 Apr '18

========================================================================== WST 2018 - Call for Papers 16th International Workshop on Termination July 18-19, 2018, Oxford, United Kingdom http://wst2018.webs.upv.es/ ========================================================================== NEW: Deadline extended to April 30, 2018 NEW: Akihisa Yamada, WST 2018 invited speaker The Workshop on Termination (WST) traditionally brings together, in an informal setting, researchers interested in all aspects of termination, whether this interest be practical or theoretical, primary or derived. The workshop also provides a ground for cross-fertilization of ideas from the different communities interested in termination (e.g., working on computational mechanisms, programming languages, software engineering, constraint solving, etc.). The friendly atmosphere enables fruitful exchanges leading to joint research and subsequent publications. The workshop is held as part of the 2018 Federated Logic Conference (FLoC 2018) http://www.floc2018.org/ IMPORTANT DATES: * submission deadline: April 30, 2018 (extended) * notification: May 28, 2018 * final version due: June 11, 2018 * workshop: July 18-19, 2018 TOPICS: The 16th International Workshop on Termination welcomes contributions on all aspects of termination. In particular, papers investigating applications of termination (for example in complexity analysis, program analysis and transformation, theorem proving, program correctness, modeling computational systems, etc.) are very welcome. Topics of interest include (but are not limited to): * abstraction methods in termination analysis * certification of termination and complexity proofs * challenging termination problems * comparison and classification of termination methods * complexity analysis in any domain * implementation of termination methods * non-termination analysis and loop detection * normalization and infinitary normalization * operational termination of logic-based systems * ordinal notation and subrecursive hierarchies * SAT, SMT, and constraint solving for (non-)termination analysis * scalability and modularity of termination methods * termination analysis in any domain (lambda calculus, declarative programming, rewriting, transition systems, etc.) * well-founded relations and well-quasi-orders COMPETITION: Since 2003, the catalytic effect of WST to stimulate new research on termination has been enhanced by the celebration of the Termination Competition and its continuously developing problem databases containing thousands of programs as challenges for termination analysis in different categories, see http://termination-portal.org/wiki/Termination_Competition In 2018, the Termination Competition will run in parallel with FLoC 2018. More details will be provided in a dedicated announcement on the competition. PROGRAM COMMITTEE: Cristina Borralleras - U. de Vic Ugo Dal Lago - U. degli Studi di Bologna Carsten Fuhs - Birkbeck, U. of London Samir Genaim - U. Complutense de Madrid Juergen Giesl - RWTH Aachen Raul Gutiérrez - U. Politecnica de València Keiichirou Kusakari - Gifu University Salvador Lucas (chair) - U. Politecnica de Valencia Fred Mesnard - U. de La Reunion Aart Middeldorp - U. of Innsbruck Albert Rubio - U. Politecnica de Catalunya Rene Thiemann - U. of Innsbruck Caterina Urban - ETH Zürich INVITED SPEAKERS: Akihisa Yamada - NII Japan SUBMISSION: Submissions are short papers/extended abstracts which should not exceed 5 pages. There will be no formal reviewing. In particular, we welcome short versions of recently published articles and papers submitted elsewhere. The program committee checks relevance and provides additional feedback for each submission. The accepted papers will be made available electronically before the workshop. Papers should be submitted electronically via the submission page: https://easychair.org/conferences/?conf=wst2018 Please, use LaTeX and the LIPIcs style file http://drops.dagstuhl.de/styles/lipics/lipics-authors.tgz to prepare your submission.

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Performance of TL-calculations
by Dmitry Olshansky 13 Apr '18

13 Apr '18

Hello, cafe, The main problem I have when using promising type-level calculation is compile time. E.g. I have > type T = ... :: [Symbol] Now I don't know the order of Symbols in T. But I want to sort it before using for some reasons. I can define > type T1 = Sort T -- where Sort is from Singletons library but T1 is only type synonym and long type-level calculation will be done in any places where I use T1. So I will have problems with compile-time performance. Probably I would overcome this if I can define > class X x where ... > instance X T1 where ... but I can't do it because can't define instances for (non-injective) Type Families. Is there any workaround? Are there any plans to make it better? Are there any hidden problems to make an analog of CAF on the type level? Best regards, Dmitry

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OneTuple unmaintained
by ☂Josh Chia (謝任中) 13 Apr '18

13 Apr '18

OneTuple needs an update for compatibility with GHC 8.4. I emailed the listed maintained but the email bounced. I would like to take over the package if there are no other takers. Josh

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using type variables in type declarations inside function
by Dennis Raddle 12 Apr '18

12 Apr '18

Let's say I've written a function on three types. myFunc :: a -> b -> c myFunc x y z = ... where helper :: a -> [b] helper xx = ... Notice that I'm attempting to declare 'helper' using my type variables. I've noticed that this results in an error. Is this actually possible, and how? D

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Unplanned Hackage Downtime
by Gershom B 12 Apr '18

12 Apr '18

I made a terrible administrative snafu, and we need to take some time to restore Hackage. Luckily we have better mirroring in place now, so cabal-install should be able to fall back automatically to mirrors. If this does not work, you can use http://objects-us-west-1.dream.io/hackage-mirror/ or http://hackage.fpcomplete.com/ manually. Best (and sincere apologies), Gershom

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hackage style
by Ben Franksen 11 Apr '18

11 Apr '18

The new hackage style has nice colors but severe problems w.r.t. readability. The right column with the package meta data causes the Readme text to be cut off. This make it almost impossible to read it. I attached a screenshot for illustration. Cheers Ben

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Join a transformer
by Michael Snoyman 11 Apr '18

11 Apr '18

I'm wondering if this pattern exists and has a name. We have the concept of joining a Monad: join :: Monad m => m (m a) -> ma How about joining a monad transformer? joinT :: (Monad m, MonadTrans t) => t (t m) a -> t m a I believe implementing this in terms of MonadTransControl[1] might be possible, but I was wondering if there's an already existing idiom for this. Michael [1] http://haddocks.fpcomplete.com/fp/7.4.2/20130301-40/monad-control/Control-M…

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