*Top Picks:* - Tony Day, Brisbane-based investment strategist and high-frequency-trading hacker, rides 100% idiomatic Haskell http://tonyday567.github.io/blog/mvc-todo/ into the Single Page (web)-App http://en.wikipedia.org/wiki/Single-page_application space. How? He spins the GHCJS transpiler on Gabriel Gonzalez's Model-View-Controller library to obtain his own TodoMVC benchmark demo http://tonyday567.github.io/static/index-auto.html. Per GHCJS, the production spans multi-megabytes of javascript. Not to be missed: auto-run, i.e. click the QuickCheck-powered checkbox labeled "Let haskell do the work." Github repo https://github.com/tonyday567/mvc-todo. Along the way, he discovers how crippled Javascript is without sum types. As noted on HN https://news.ycombinator.com/item?id=9591868#up_9601842, "Typos and missing cases represent a very large set of trivial bugs." He believes superior FP features such as sum types makes it "much harder for haskell to avoid success." Woe is us. /r/haskell http://www.reddit.com/r/haskell/comments/36y9jc/haskell_as_an_mvc_framework/ - Michael Walker, a Ph.D. student at York, reveals http://www.reddit.com/r/haskell/comments/37dv8y/what_side_projects_have_you_... his personal book-collection management web-app http://www.barrucadu.co.uk/bookdb/ that runs on top of persistent https://hackage.haskell.org/package/persistent, WAI https://hackage.haskell.org/package/wai, and web-routes https://hackage.haskell.org/package/web-routes. Public domain. https://github.com/barrucadu/bookdb - David Christiansen announces on /r/haskell http://www.reddit.com/r/haskell/comments/36az3n/idris_0918_released_with_fan... Idris 0.9.18 http://www.idris-lang.org/idris-0-9-18-released/ with fancier records. Top comment says Idris is more type-friendly than Haskell despite the "esoteric academics behind dependent type theory." Why? Because Idris, helpfully offers suggestions that turn ill- into well-typed code. Haskell doesn't. - Remember JP Moresmau dropping EclipseFP http://haskell.1045720.n5.nabble.com/Haskell-Weekly-News-tp5809360.html? Can Leksah take its place? Hamish Mackenzie announces a 7.10-ready Leksah 0.15.0 https://github.com/leksah/leksah/wiki/Leksah-0.15.0 on /r/haskell http://www.reddit.com/r/haskell/comments/37emp2/leksah_0150/. Top new feature? Support for GHCJS, which excites Phil Freeman of PureScript fame. Here's a 2min video clip on How to make a ghcjs-dom application in Leksah https://www.youtube.com/watch?v=zQnExdDL63c. - Roman Cheplyaka writes a short 'n sweet tutorial https://ro-che.info/articles/2015-05-28-force-list on how a list may be variously forced. He summarizes the similarities and differences in a table that goes from the shallowestly evaluated seq () to forceSpine to forceElements to the deepest rnf. /r/haskell http://www.reddit.com/r/haskell/comments/37ky62/how_to_force_a_list/ - Justin Leitgeb, Rails developer and Co-Founder / CTO of Stack Builders, a Haskell-enabled software consultancy, deprioritizes learning Clojure, Go, Erlang, and Scala in favor of Agda, Coq, Idris, Elm, and Liquid Haskell http://www.stackbuilders.com/news/another-personal-programming-language-road.... He will invest a couple of weeks at the Oregon PL Summer School starting June 15 https://www.cs.uoregon.edu/research/summerschool/summer15/. - Tony Morris announces a three-day Haskell-based Intro to FP course in Melbourne, July 21-23 this year. Pitched at beginners, it features learning by coding. Free; application deadline: July 10 https://groups.google.com/forum/#!topic/nicta-fp/Dnq-oh4nJbg. - By popular request http://haskell.1045720.n5.nabble.com/Workshop-on-Type-Inference-and-Automate..., František Farka and his team recorded all of a workshop on type inference in Dundee, Scotland http://staff.computing.dundee.ac.uk/frantisekfarka/tiap/ held a couple of weeks ago. Highly-viewed talks https://www.youtube.com/user/qmbevents/videos include Edwin Brady http://staff.computing.dundee.ac.uk/frantisekfarka/tiap/#edwin on implementing dependent types in Idris and Conor McBride http://staff.computing.dundee.ac.uk/frantisekfarka/tiap/#conor on "Type Inference Needs Revolution." /r/haskell http://www.reddit.com/r/haskell/comments/36dfcx/workshop_on_type_inference_a... - Michael Hicks at UMD, PC chair of POPL 2012, writes a PL research apologia http://www.pl-enthusiast.net/2015/05/27/what-is-pl-research-and-how-is-it-us... cum pitch for new grad students. An informal poll he did shows PL Ph.D.s get good jobs. He explains that "The ethos of PL research is to not just find solutions to important problems, but to find the *best expression of those solutions.*" As ethos specimens, he gives three: probabilistic programming, incremental computation a.k.a. self-adaptive computation, and authenticated data structures (see LambdaAuth http://amiller.github.io/lambda-auth/). HN-worthy https://news.ycombinator.com/item?id=9614178. - Jan Stolarek gives a glimpse http://lambda.jstolarek.com/2015/05/injective-type-families-for-haskell/ of GHC's new injective type families feature, which is joint research with SPJ and Richard Eisenberg. It brings Haskell one step closer to having a notion of type functions as opposed to mere 'constructors.' The feature is useful in type-level hacking. It allows the arguments of a type family to be inferred solely by result type. But Lennart Augustsson on /r/haskell http://www.reddit.com/r/haskell/comments/37bvh0/injective_type_families_for_... gives a trivial example where even when a type family isn't injective, its argument can still be inferred knowing a particular result type. He regrets that GHC doesn't do this. - Joe Nelson uploads the video and a summary http://begriffs.com/posts/2015-05-24-safe-haskell.html of Kristen Kozak introducing the Safe Haskell extension to the SF Bay Area Haskell Users Group http://www.meetup.com/Bay-Area-Haskell-Users-Group/events/220312001/ on May 12. Slides here http://wordroute.com/grayjay/safe-haskell.pdf. Redditor beerdude26 http://www.reddit.com/r/haskell/comments/37a1cq/using_the_safe_haskell_langu... adds the link to and tidies up the Safe Haskell wiki https://wiki.haskell.org/Safe_Haskell entry. - Out of frustration with existing Windows GUI FFIs, Luka Horvat http://lukahorvat.github.io/programming/2015/05/24/haskellforms/ creates bindings for WinForms https://github.com/LukaHorvat/HaskellForms, Microsoft's .NET menus-and-widgets library. He binds to F# instead of lower-level C++/C# because it's easier. /r/haskell http://www.reddit.com/r/haskell/comments/37464x/haskellforms_winforms_bindin... - Gabriel Gonzalez http://www.haskellforall.com/2015/05/the-internet-of-code.html demoes another piece of Morte, what he describes as his "pandoc for programming languages." He prototypes "distributing typed code over the internet where the unit of compilation is individual expressions." /r/haskell http://www.reddit.com/r/haskell/comments/36d12v/haskell_for_all_the_internet... - Taylor Fausak forsakes TagSoup https://hackage.haskell.org/package/tagsoup and scrapes websites http://taylor.fausak.me/2015/05/21/scraping-websites-with-haskell/ the hard way using xml-conduit. He concludes that it's "tougher than doing the same thing in scripting languages, but hopefully easier than [his blog readers] expected." - Stuart Popejoy writes a monad tutorial http://slpopejoy.github.io/posts/Effectful01.html. A redditor finds it an "entertaining explanation of monads." Another asks the OOP-ish question: are monads "basically wrappers that contain 'impure' data and actions with some common functions?" See /r/haskell http://www.reddit.com/r/haskell/comments/374c3o/effectful_haskell_io_monads_... *Announcement:* Semen Trygubenko has stepped down from publishing his edition of HWN. Losing him means there will be no issue next week. *Quotes of the Week:* - UnoOuzo https://twitter.com/UnoOuzo/status/601658244201848832: "The type of my love is parametrically polymorphic. It is unbounded." Looking into ways to cite this in my thesis. - Conor McBride http://www.reddit.com/r/haskell/comments/36y9jc/haskell_as_an_mvc_framework/...: Algebra is a posh way of saying "construction kit". - Michael Hicks http://www.pl-enthusiast.net/2015/05/27/what-is-pl-research-and-how-is-it-us...: The ethos of PL research is to not just find solutions to important problems, but to find the *best expression of those solutions. * - There is a fountain of youth: it is your mind, your talents, the creativity you bring to your life and the lives of people you love. When you learn to tap this source, you will truly have defeated age. -- Sophia Loren -- Kim-Ee