<div>   Welcome to issue 199 of the HWN, a newsletter covering developments in</div><div>   the Haskell community. This release covers the week of September 4 to</div><div>   10, 2011.</div><div><br></div><div>Announcements</div>

<div><br></div><div>   Johannes Waldmann open the invitation to the 6th Haskell in Leipzig</div><div>   workshop, on October 7, 2011. It &quot;will present an absolutely thrilling</div><div>   mixture of tutorials and talks, with special enphasis on parallel</div>

<div>   programming.&quot;</div><div>   [1] <a href="http://goo.gl/u0PwF">http://goo.gl/u0PwF</a></div><div><br></div><div>New and Updated Projects</div><div><br></div><div>   * Hs2lib (Phyx; v-0.5.5) A preprocesor and library which allow you</div>

<div>     to create dynamic libs from arbitrary annotated Haskell programs</div><div>     with one click. It also allows you to use the generated lib in C,</div><div>     C++, and C# just by including the generated header files.</div>

<div>     [2] <a href="http://goo.gl/xCSXc">http://goo.gl/xCSXc</a></div><div><br></div><div>   * Netwire (Ertugrul Soeylemez; 1.2.0) Lots of new features!</div><div>     [3] <a href="http://goo.gl/VCwb1">http://goo.gl/VCwb1</a></div>

<div><br></div><div>   * network-address (Sebastian Nowicki; 0.2.0) Provides data</div><div>     structures and textual representation of network addresses (IPv4,</div><div>     IPv6, subnets).</div><div>     [4] <a href="http://goo.gl/DBRI6">http://goo.gl/DBRI6</a></div>

<div><br></div><div>   * Webrexp (Vincent Berthoux; 1.1) A web scraping command line</div><div>     utility.</div><div>     [5] <a href="http://goo.gl/OlovQ">http://goo.gl/OlovQ</a></div><div><br></div><div>   * eddie (Mike Meyer; 0.5) Is a tool for applying haskell filters</div>

<div>     to text files via the unix command line.</div><div>     [6] <a href="http://goo.gl/NPc0b">http://goo.gl/NPc0b</a></div><div><br></div><div>   * cabal-ghci (Etienne Laurin; 0.1) Package to ease the development</div>

<div>     of projects using cabal.</div><div>     [7] <a href="http://goo.gl/fiDKZ">http://goo.gl/fiDKZ</a></div><div><br></div><div>Quotes of the Week</div><div><br></div><div>   * gosu: Type parameters are covariant. This is not sound, and that</div>

<div>     does not matter.</div><div>   * turtlesalltheway: if haskell is so great why cant it improve itself</div><div>   * mm_freak: bosses are generally quite strong, static and lazy</div><div>   * cmccann: newtype Natural = N { denature :: Integer }</div>

<div><br></div><div>Top Reddit Stories</div><div><br></div><div>   * Constraint Kinds for GHC</div><div>     Domain: <a href="http://blog.omega-prime.co.uk">blog.omega-prime.co.uk</a>, Score: 115, Comments: 12</div><div>
     On Reddit: [8] <a href="http://goo.gl/bCXgf">http://goo.gl/bCXgf</a></div>
<div>     Original: [9] <a href="http://goo.gl/7aWzn">http://goo.gl/7aWzn</a></div><div><br></div><div>   * Yesod :: The Limitations of Haskell</div><div>     Domain: <a href="http://yesodweb.com">yesodweb.com</a>, Score: 108, Comments: 42</div>

<div>     On Reddit: [10] <a href="http://goo.gl/5q7wW">http://goo.gl/5q7wW</a></div><div>     Original: [11] <a href="http://goo.gl/gisIh">http://goo.gl/gisIh</a></div><div><br></div><div>   * Frege: haskell like language on JVM </div>

<div>     (tries to adhere to haskell 2010 where possible)</div><div>     Domain: <a href="http://code.google.com">code.google.com</a>, Score: 58, Comments: 58</div><div>     On Reddit: [12] <a href="http://goo.gl/6KWEg">http://goo.gl/6KWEg</a></div>

<div>     Original: [13] <a href="http://goo.gl/56AkX">http://goo.gl/56AkX</a></div><div><br></div><div>   * Sharing in Haskell – How the let and lambda constructs give </div><div>     a precise way to control sharing</div>

<div>     Domain: <a href="http://neilmitchell.blogspot.com">neilmitchell.blogspot.com</a>, Score: 34, Comments: 18</div><div>     On Reddit: [14] <a href="http://goo.gl/Uf1vq">http://goo.gl/Uf1vq</a></div><div>     Original: [15] <a href="http://goo.gl/4Hmfu">http://goo.gl/4Hmfu</a></div>

<div><br></div><div>   * Let&#39;s play a game : How to implement functions from their type </div><div>     signatures</div><div>     Domain: <a href="http://blog.ezyang.com">blog.ezyang.com</a>, Score: 24, Comments: 13</div>

<div>     On Reddit: [16] <a href="http://goo.gl/T2FiD">http://goo.gl/T2FiD</a></div><div>     Original: [17] <a href="http://goo.gl/SmbYO">http://goo.gl/SmbYO</a></div><div><br></div><div>   * Impredicativity + injectivity + type case analysis = inconsistency </div>

<div>     (Russell paradox) :: Oleg</div><div>     Domain: <a href="http://okmij.org">okmij.org</a>, Score: 23, Comments: 10</div><div>     On Reddit: [18] <a href="http://goo.gl/zoThI">http://goo.gl/zoThI</a></div><div>
     Original: [19] <a href="http://goo.gl/jFr5U">http://goo.gl/jFr5U</a></div>
<div><br></div><div>   * Functional Pearls</div><div>     Domain: <a href="http://haskell.org">haskell.org</a>, Score: 23, Comments: 1</div><div>     On Reddit: [20] <a href="http://goo.gl/RVyng">http://goo.gl/RVyng</a></div>

<div>     Original: [21] <a href="http://goo.gl/1A7t0">http://goo.gl/1A7t0</a></div><div><br></div><div>   * An EventSource broker written in Haskell</div><div>     Domain: <a href="http://mathias-biilmann.net">mathias-biilmann.net</a>, Score: 22, Comments: 0</div>

<div>     On Reddit: [22] <a href="http://goo.gl/7yywu">http://goo.gl/7yywu</a></div><div>     Original: [23] <a href="http://goo.gl/Y5mGj">http://goo.gl/Y5mGj</a></div><div><br></div><div>   * Haskell For Kids: Week 4</div>

<div>     Domain: <a href="http://cdsmith.wordpress.com">cdsmith.wordpress.com</a>, Score: 22, Comments: 2</div><div>     On Reddit: [24] <a href="http://goo.gl/KwlqD">http://goo.gl/KwlqD</a></div><div>     Original: [25] <a href="http://goo.gl/xlNh2">http://goo.gl/xlNh2</a></div>

<div><br></div><div>   * apfelmus - Vault - a persistent store for values of arbitrary types</div><div>     Domain: <a href="http://apfelmus.nfshost.com">apfelmus.nfshost.com</a>, Score: 19, Comments: 2</div><div>     On Reddit: [26] <a href="http://goo.gl/VAE4n">http://goo.gl/VAE4n</a></div>

<div>     Original: [27] <a href="http://goo.gl/vvQ7A">http://goo.gl/vvQ7A</a></div><div><br></div><div>   * Tau is available in Haskell, you can safely avoid Pi</div><div>     Domain: <a href="http://hackage.haskell.org">hackage.haskell.org</a>, Score: 19, Comments: 26</div>

<div>     On Reddit: [28] <a href="http://goo.gl/u5GN8">http://goo.gl/u5GN8</a></div><div>     Original: [29] <a href="http://goo.gl/VnrMh">http://goo.gl/VnrMh</a></div><div><br></div><div>   * Zipper from any Traversable :: Oleg</div>

<div>     Domain: <a href="http://okmij.org">okmij.org</a>, Score: 18, Comments: 2</div><div>     On Reddit: [30] <a href="http://goo.gl/xi4ZF">http://goo.gl/xi4ZF</a></div><div>     Original: [31] <a href="http://goo.gl/nqZ3T">http://goo.gl/nqZ3T</a></div>

<div><br></div><div>Top StackOverflow Questions</div><div><br></div><div>   * More on generic Scala functions</div><div>     votes: 20, answers: 4</div><div>     Read on SO: [32] <a href="http://goo.gl/DGH14">http://goo.gl/DGH14</a></div>

<div><br></div><div>   * Why is a “type class” called “type class”?</div><div>     votes: 20, answers: 2</div><div>     Read on SO: [33] <a href="http://goo.gl/YbVXX">http://goo.gl/YbVXX</a></div><div><br></div><div>   * Is there a Haskell idiom for updating a nested data structure?</div>

<div>     votes: 14, answers: 2</div><div>     Read on SO: [34] <a href="http://goo.gl/jKEjv">http://goo.gl/jKEjv</a></div><div><br></div><div>   * How to tell if a list is infinite?</div><div>     votes: 14, answers: 4</div>

<div>     Read on SO: [35] <a href="http://goo.gl/fc3e6">http://goo.gl/fc3e6</a></div><div><br></div><div>   * Select random element from a set, faster than linear time (Haskell)</div><div>     votes: 9, answers: 5</div>
<div>
     Read on SO: [36] <a href="http://goo.gl/IRJf3">http://goo.gl/IRJf3</a></div><div><br></div><div>   * GHC not optimising modules other than the main module</div><div>     votes: 9, answers: 0</div><div>     Read on SO: [37] <a href="http://goo.gl/8Ephm">http://goo.gl/8Ephm</a></div>

<div><br></div><div>   * A chess board representation in Haskell</div><div>     votes: 8, answers: 4</div><div>     Read on SO: [38] <a href="http://goo.gl/iSM7d">http://goo.gl/iSM7d</a></div><div><br></div><div>   * How to cap memory usage of Haskell threads</div>

<div>     votes: 7, answers: 2</div><div>     Read on SO: [39] <a href="http://goo.gl/dvLnE">http://goo.gl/dvLnE</a></div><div><br></div><div>   * Is this Haskell type inference in action, or something else?</div><div>     votes: 7, answers: 2</div>

<div>     Read on SO: [40] <a href="http://goo.gl/hTaK7">http://goo.gl/hTaK7</a></div><div><br></div><div>   * Assymmetry in the bind function</div><div>     votes: 6, answers: 7</div><div>     Read on SO: [41] <a href="http://goo.gl/KqMTn">http://goo.gl/KqMTn</a></div>

<div><br></div><div>About the Haskell Weekly News</div><div><br></div><div>   To help create new editions of this newsletter, please send stories to</div><div>   <a href="mailto:dstcruz@gmail.com">dstcruz@gmail.com</a>.</div>

<div><br></div><div>   Until next time,</div><div>   Daniel Santa Cruz</div><div><br></div><div>References</div><div><br></div><div>   1. <a href="http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/92287">http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/92287</a></div>

<div>   2. <a href="http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/92182">http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/92182</a></div><div>   3. <a href="http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/92225">http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/92225</a></div>

<div>   4. <a href="http://permalink.gmane.org/gmane.comp.lang.haskell.general/18916">http://permalink.gmane.org/gmane.comp.lang.haskell.general/18916</a></div><div>   5. <a href="http://permalink.gmane.org/gmane.comp.lang.haskell.general/18929">http://permalink.gmane.org/gmane.comp.lang.haskell.general/18929</a></div>

<div>   6. <a href="http://permalink.gmane.org/gmane.comp.lang.haskell.general/18930">http://permalink.gmane.org/gmane.comp.lang.haskell.general/18930</a></div><div>   7. <a href="http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/92279">http://permalink.gmane.org/gmane.comp.lang.haskell.cafe/92279</a></div>

<div>   8. <a href="http://blog.omega-prime.co.uk/?p=127">http://blog.omega-prime.co.uk/?p=127</a></div><div>   9. <a href="http://www.reddit.com/r/haskell/comments/kbf14/constraint_kinds_for_ghc/">http://www.reddit.com/r/haskell/comments/kbf14/constraint_kinds_for_ghc/</a></div>

<div>  10. <a href="http://www.yesodweb.com/blog/2011/09/limitations-of-haskell">http://www.yesodweb.com/blog/2011/09/limitations-of-haskell</a></div><div>  11. <a href="http://www.reddit.com/r/haskell/comments/k4lc4/yesod_the_limitations_of_haskell/">http://www.reddit.com/r/haskell/comments/k4lc4/yesod_the_limitations_of_haskell/</a></div>

<div>  12. <a href="http://code.google.com/p/frege/">http://code.google.com/p/frege/</a></div><div>  13. <a href="http://www.reddit.com/r/haskell/comments/kadx6/frege_haskell_like_language_on_jvm_tries_to/">http://www.reddit.com/r/haskell/comments/kadx6/frege_haskell_like_language_on_jvm_tries_to/</a></div>

<div>  14. <a href="http://neilmitchell.blogspot.com/2011/09/sharing-in-haskell.html">http://neilmitchell.blogspot.com/2011/09/sharing-in-haskell.html</a></div><div>  15. <a href="http://www.reddit.com/r/haskell/comments/k4bq9/sharing_in_haskell_how_the_let_and_lambda/">http://www.reddit.com/r/haskell/comments/k4bq9/sharing_in_haskell_how_the_let_and_lambda/</a></div>

<div>  16. <a href="http://blog.ezyang.com/2011/09/lets-play-a-game/">http://blog.ezyang.com/2011/09/lets-play-a-game/</a></div><div>  17. <a href="http://www.reddit.com/r/haskell/comments/k5okh/lets_play_a_game_how_to_implement_functions_from/">http://www.reddit.com/r/haskell/comments/k5okh/lets_play_a_game_how_to_implement_functions_from/</a></div>

<div>  18. <a href="http://okmij.org/ftp/Haskell/impredicativity-bites.html">http://okmij.org/ftp/Haskell/impredicativity-bites.html</a></div><div>  19. <a href="http://www.reddit.com/r/haskell/comments/k5bdb/impredicativity_injectivity_type_case_analysis/">http://www.reddit.com/r/haskell/comments/k5bdb/impredicativity_injectivity_type_case_analysis/</a></div>

<div>  20. <a href="http://www.haskell.org/haskellwiki/Research_papers/Functional_pearls">http://www.haskell.org/haskellwiki/Research_papers/Functional_pearls</a></div><div>  21. <a href="http://www.reddit.com/r/haskell/comments/kb3w5/functional_pearls/">http://www.reddit.com/r/haskell/comments/kb3w5/functional_pearls/</a></div>

<div>  22. <a href="http://mathias-biilmann.net/posts/2011/9/a-haskell-eventsource-broker">http://mathias-biilmann.net/posts/2011/9/a-haskell-eventsource-broker</a></div><div>  23. <a href="http://www.reddit.com/r/haskell/comments/k6fva/an_eventsource_broker_written_in_haskell/">http://www.reddit.com/r/haskell/comments/k6fva/an_eventsource_broker_written_in_haskell/</a></div>

<div>  24. <a href="http://cdsmith.wordpress.com/2011/09/10/haskell-for-kids-week-4/">http://cdsmith.wordpress.com/2011/09/10/haskell-for-kids-week-4/</a></div><div>  25. <a href="http://www.reddit.com/r/haskell/comments/kbqn0/haskell_for_kids_week_4/">http://www.reddit.com/r/haskell/comments/kbqn0/haskell_for_kids_week_4/</a></div>

<div>  26. <a href="http://apfelmus.nfshost.com/blog/2011/09/04-vault.html">http://apfelmus.nfshost.com/blog/2011/09/04-vault.html</a></div><div>  27. <a href="http://www.reddit.com/r/haskell/comments/k4l6c/apfelmus_vault_a_persistent_store_for_values_of/">http://www.reddit.com/r/haskell/comments/k4l6c/apfelmus_vault_a_persistent_store_for_values_of/</a></div>

<div>  28. <a href="http://hackage.haskell.org/package/tau">http://hackage.haskell.org/package/tau</a></div><div>  29. <a href="http://www.reddit.com/r/haskell/comments/kazfn/tau_is_available_in_haskell_you_can_safely_avoid/">http://www.reddit.com/r/haskell/comments/kazfn/tau_is_available_in_haskell_you_can_safely_avoid/</a></div>

<div>  30. <a href="http://okmij.org/ftp/continuations/zipper.html#traversable">http://okmij.org/ftp/continuations/zipper.html#traversable</a></div><div>  31. <a href="http://www.reddit.com/r/haskell/comments/k5bci/zipper_from_any_traversable_oleg/">http://www.reddit.com/r/haskell/comments/k5bci/zipper_from_any_traversable_oleg/</a></div>

<div>  32. <a href="http://stackoverflow.com/questions/7337582/more-on-generic-scala-functions">http://stackoverflow.com/questions/7337582/more-on-generic-scala-functions</a></div><div>  33. <a href="http://stackoverflow.com/questions/7360024/why-is-a-type-class-called-type-class">http://stackoverflow.com/questions/7360024/why-is-a-type-class-called-type-class</a></div>

<div>  34. <a href="http://stackoverflow.com/questions/7365425/is-there-a-haskell-idiom-for-updating-a-nested-data-structure">http://stackoverflow.com/questions/7365425/is-there-a-haskell-idiom-for-updating-a-nested-data-structure</a></div>

<div>  35. <a href="http://stackoverflow.com/questions/7371730/how-to-tell-if-a-list-is-infinite">http://stackoverflow.com/questions/7371730/how-to-tell-if-a-list-is-infinite</a></div><div>  36. <a href="http://stackoverflow.com/questions/7349080/select-random-element-from-a-set-faster-than-linear-time-haskell">http://stackoverflow.com/questions/7349080/select-random-element-from-a-set-faster-than-linear-time-haskell</a></div>

<div>  37. <a href="http://stackoverflow.com/questions/7367070/ghc-not-optimising-modules-other-than-the-main-module">http://stackoverflow.com/questions/7367070/ghc-not-optimising-modules-other-than-the-main-module</a></div>

<div>  38. <a href="http://stackoverflow.com/questions/7309554/a-chess-board-representation-in-haskell">http://stackoverflow.com/questions/7309554/a-chess-board-representation-in-haskell</a></div><div>  39. <a href="http://stackoverflow.com/questions/7297654/how-to-cap-memory-usage-of-haskell-threads">http://stackoverflow.com/questions/7297654/how-to-cap-memory-usage-of-haskell-threads</a></div>

<div>  40. <a href="http://stackoverflow.com/questions/7342222/is-this-haskell-type-inference-in-action-or-something-else">http://stackoverflow.com/questions/7342222/is-this-haskell-type-inference-in-action-or-something-else</a></div>

<div>  41. <a href="http://stackoverflow.com/questions/7319424/assymmetry-in-the-bind-function">http://stackoverflow.com/questions/7319424/assymmetry-in-the-bind-function</a></div><div><br></div>