Welcome to issue 268 of the HWN, an issue covering crowd-sourced bits
of information about Haskell from around the web. This issue covers the
week of May 12 to 25, 2013.

Quotes of the Week

   * tikhonjelvis: the lesson is that the fix function exists to "fix"
     any type problems you may encounter

   * shachaf: The trouble with peano arithmetic is that it stops at 88.

   * Peaker: Python's dynamic nature adds slowness and unsafety, but
     doesn't actually make things more expressive

   * sj4nz: Programming in weakly-typed languages forever after will
     feel like working with punch cards. Send in your program to the
     nodejs interpreter and hope for a result to come back.

   * xplat: if you want to carry your machete all the time and not make
     people nervous, you need to constantly blaze trails

   * otters: heh, F# is just the unboxed version of F

   * quchen: This was the first time in months that I thought
     imperatively. Conclusion: 1. it complicated things, 2. it was
     refreshing

   * cmccann: I still kind of expect that the next standard will be
     haskell2017 or something, and all it will do is a minor change to
     lexical syntax of comments that fixes nothing but nevertheless
     breaks 20% of hackage.

   * cmccann: [on reimplementing cryptography in pure Haskell] writing
     in Haskell lets you use type safety to ensure that all the security
     holes you create are subtle instead of obvious.

Top Reddit Stories

   * Haskell in Production [slides]
     Domain: mth.io, Score: 60, Comments: 114
     On Reddit: [1] http://goo.gl/ldnv0
     Original: [2] http://goo.gl/tMjTd

   * B-trees with GADTs
     Domain: matthew.brecknell.net, Score: 56, Comments: 6
     On Reddit: [3] http://goo.gl/Sjf9U
     Original: [4] http://goo.gl/sQnYW


   * Yearly revisions to the Haskell language: who killed Haskell Prime?
     Domain: self.haskell, Score: 54, Comments: 19
     On Reddit: [5] http://goo.gl/5GWKg
     Original: [6] http://goo.gl/5GWKg

   * Elm paper accepted at PLDI: Asynchronous FRP for GUIs!
     Domain: people.seas.harvard.edu, Score: 51, Comments: 4
     On Reddit: [7] http://goo.gl/iYiyh
     Original: [8] http://goo.gl/98jft

   * The complete correctness of sorting [Agda]
     Domain: twanvl.nl, Score: 49, Comments: 5
     On Reddit: [9] http://goo.gl/PLH6m
     Original: [10] http://goo.gl/RQGZn

   * Anatomy of an MVar operation
     Domain: blog.ezyang.com, Score: 47, Comments: 7
     On Reddit: [11] http://goo.gl/7miao
     Original: [12] http://goo.gl/3ZHSI

   * Typing Haskell in Haskell
     Domain: web.cecs.pdx.edu, Score: 44, Comments: 34
     On Reddit: [13] http://goo.gl/q1ghy
     Original: [14] http://goo.gl/M5csQ

   * STM in Haskell is better because of types
     Domain: joeyh.name, Score: 44, Comments: 8
     On Reddit: [15] http://goo.gl/wj9Ab
     Original: [16] http://goo.gl/fmLM1

   * Typed Template Haskell ready for testing in GHC
     Domain: haskell.org, Score: 44, Comments: 13
     On Reddit: [17] http://goo.gl/he61y
     Original: [18] http://goo.gl/YJIZB

   * A detailed look at GHC's STM implementation from a non-GHC hacker
     Domain: fryguybob.github.io, Score: 38, Comments: 11
     On Reddit: [19] http://goo.gl/pTp2c
     Original: [20] http://goo.gl/4oe3Y

   * New Haskell Communities and Activity Report (May 2013) is out
     Domain: haskell.org, Score: 37, Comments: 2
     On Reddit: [21] http://goo.gl/P2kz1
     Original: [22] http://goo.gl/YoIE4

   * Three examples of problems with Lazy I/O
     Domain: newartisans.com, Score: 36, Comments: 31
     On Reddit: [23] http://goo.gl/reKqZ
     Original: [24] http://goo.gl/ZagPt

   * Understanding the Yoneda Lemma
     Domain: fpcomplete.com, Score: 35, Comments: 48
     On Reddit: [25] http://goo.gl/RUZ4h
     Original: [26] http://goo.gl/xbAJj

   * Simon Peyton Jones to keynote Haskell eXchange 2013!
     Domain: skillsmatter.com, Score: 35, Comments: 2
     On Reddit: [27] http://goo.gl/DlfRt
     Original: [28] http://goo.gl/5lpwh

   * Greg Hale's "Functional programming elevator pitch"
     Domain: fpcomplete.com, Score: 34, Comments: 8
     On Reddit: [29] http://goo.gl/gbhX3
     Original: [30] http://goo.gl/QrrxP

   * FP Complete is looking for a Technical Sales Engineer and Support Specialist
     Domain: fpcomplete.com, Score: 32, Comments: 1
     On Reddit: [31] http://goo.gl/nYNci
     Original: [32] http://goo.gl/VGCoa

   * A Typed Markup Language Based On Haskell
     Domain: blog.functorial.com, Score: 31, Comments: 9
     On Reddit: [33] http://goo.gl/eLLjV
     Original: [34] http://goo.gl/wFxcv

   * Announcing: Snap Framework v0.12
     Domain: snapframework.com, Score: 28, Comments: 2
     On Reddit: [35] http://goo.gl/5wYLk
     Original: [36] http://goo.gl/KibyP

   * John Wiegley's "Understanding Continuations", on School of Haskell
     Domain: fpcomplete.com, Score: 27, Comments: 17
     On Reddit: [37] http://goo.gl/ZT7d6
     Original: [38] http://goo.gl/YitVR

Top StackOverflow Questions

   * Why are if expressions frowned upon in Haskell?
     votes: 20, answers: 6
     Read on SO: [39] http://goo.gl/NejhX

   * Haskell: `Map (a,b) c` versus `Map a (Map b c)`?
     votes: 19, answers: 3
     Read on SO: [40] http://goo.gl/8f1hf

   * Why recursive `let` make space effcient?
     votes: 18, answers: 3
     Read on SO: [41] http://goo.gl/QTLYQ

   * Should do-notation be avoided in Haskell? [duplicate]
     votes: 16, answers: 7
     Read on SO: [42] http://goo.gl/MGiFr

   * Correspondence between type classes and grammar levels in the Chomsky hierarchy
     votes: 15, answers: 1
     Read on SO: [43] http://goo.gl/LRJy2

   * Calling Haskell from C#
     votes: 14, answers: 2
     Read on SO: [44] http://goo.gl/n9QB1

   * How do exceptions work in Haskell (part two)?
     votes: 13, answers: 1
     Read on SO: [45] http://goo.gl/U2GDR

   * Can a monad be a comonad?
     votes: 11, answers: 5
     Read on SO: [46] http://goo.gl/ESrc2

   * Dynamic Programming Memoization in Haskell
     votes: 11, answers: 1
     Read on SO: [47] http://goo.gl/Gp7c8

   * Employing arrows to fold a list of tuples
     votes: 11, answers: 1
     Read on SO: [48] http://goo.gl/shRWV



Until next time,
+Daniel Santa Cruz

References

   1. http://mth.io/talks/haskell-in-production/
   2. http://www.reddit.com/r/haskell/comments/1etssw/haskell_in_production_slides/
   3. http://matthew.brecknell.net/post/btree-gadt/
   4. http://www.reddit.com/r/haskell/comments/1efuog/btrees_with_gadts/
   5. http://www.reddit.com/r/haskell/comments/1esmhj/yearly_revisions_to_the_haskell_language_who/
   6. http://www.reddit.com/r/haskell/comments/1esmhj/yearly_revisions_to_the_haskell_language_who/
   7. http://people.seas.harvard.edu/~chong/pubs/pldi13-elm.pdf
   8. http://www.reddit.com/r/haskell/comments/1eie6m/elm_paper_accepted_at_pldi_asynchronous_frp_for/
   9. http://twanvl.nl/blog/agda/sorting
  10. http://www.reddit.com/r/haskell/comments/1exv2t/the_complete_correctness_of_sorting_agda/
  11. http://blog.ezyang.com/2013/05/anatomy-of-an-mvar-operation/
  12. http://www.reddit.com/r/haskell/comments/1eostu/anatomy_of_an_mvar_operation/
  13. http://web.cecs.pdx.edu/~mpj/thih/TypingHaskellInHaskell.html
  14. http://www.reddit.com/r/haskell/comments/1e6s68/typing_haskell_in_haskell/
  15. http://joeyh.name/blog/entry/the_newinwheezy_game:_STM/
  16. http://www.reddit.com/r/haskell/comments/1e8ow9/stm_in_haskell_is_better_because_of_types/
  17. http://www.haskell.org/pipermail/ghc-devs/2013-May/001255.html
  18. http://www.reddit.com/r/haskell/comments/1egfra/typed_template_haskell_ready_for_testing_in_ghc/
  19. http://fryguybob.github.io/STM-Commentary/
  20. http://www.reddit.com/r/haskell/comments/1ejgjo/a_detailed_look_at_ghcs_stm_implementation_from_a/
  21. http://haskell.org/communities/05-2013/html/report.html
  22. http://www.reddit.com/r/haskell/comments/1e601k/new_haskell_communities_and_activity_report_may/
  23. http://newartisans.com/2013/05/three-examples-of-problems-with-lazy-io
  24. http://www.reddit.com/r/haskell/comments/1e8k3k/three_examples_of_problems_with_lazy_io/
  25. https://www.fpcomplete.com/user/bartosz/understanding-yoneda
  26. http://www.reddit.com/r/haskell/comments/1eelao/understanding_the_yoneda_lemma/
  27. http://skillsmatter.com/event/scala/haskell-exchange/te-7391
  28. http://www.reddit.com/r/haskell/comments/1ewq54/simon_peyton_jones_to_keynote_haskell_exchange/
  29. https://www.fpcomplete.com/user/imalsogreg/functional-programming-elevator-pitch
  30. http://www.reddit.com/r/haskell/comments/1ewvhm/greg_hales_functional_programming_elevator_pitch/
  31. https://www.fpcomplete.com/page/product_specialist
  32. http://www.reddit.com/r/haskell/comments/1ezeng/fp_complete_is_looking_for_a_technical_sales/
  33. http://blog.functorial.com/posts/2013-05-18-Typed-Markup-Language.html
  34. http://www.reddit.com/r/haskell/comments/1elhj2/a_typed_markup_language_based_on_haskell/
  35. http://snapframework.com/blog/2013/05/15/snap-0.12-released
  36. http://www.reddit.com/r/haskell/comments/1ef3kt/announcing_snap_framework_v012/
  37. https://www.fpcomplete.com/user/jwiegley/understanding-continuations
  38. http://www.reddit.com/r/haskell/comments/1e977w/john_wiegleys_understanding_continuations_on/
  39. http://stackoverflow.com/questions/16572446/why-are-if-expressions-frowned-upon-in-haskell
  40. http://stackoverflow.com/questions/16613032/haskell-map-a-b-c-versus-map-a-map-b-c
  41. http://stackoverflow.com/questions/16632143/why-recursive-let-make-space-effcient
  42. http://stackoverflow.com/questions/16726659/should-do-notation-be-avoided-in-haskell
  43. http://stackoverflow.com/questions/16607637/correspondence-between-type-classes-and-grammar-levels-in-the-chomsky-hierarchy
  44. http://stackoverflow.com/questions/16615641/calling-haskell-from-c-sharp
  45. http://stackoverflow.com/questions/16678165/how-do-exceptions-work-in-haskell-part-two
  46. http://stackoverflow.com/questions/16551734/can-a-monad-be-a-comonad
  47. http://stackoverflow.com/questions/16585741/dynamic-programming-memoization-in-haskell
  48. http://stackoverflow.com/questions/16676758/employing-arrows-to-fold-a-list-of-tuples
  49. https://plus.google.com/105107667630152149014/about