<div>Welcome to issue 212 of the HWN, a newsletter covering developments in</div><div>the Haskell community. This issue covers top Haskell stories from</div><div>around the web found between January 11 to 21, 2012.</div><div>

<br></div><div>You can find the HTML version at:</div><div><a href="http://contemplatecode.blogspot.com/2012/01/haskell-weekly-news-issue-212.html">http://contemplatecode.blogspot.com/2012/01/haskell-weekly-news-issue-212.html</a></div>

<div><br></div><div>Quotes of the Week</div><div><br></div><div>   * shachaf: Haskell&#39;s type system is the perfect mix of useless and</div><div>     stupid.</div><div><br></div><div>   * roconnor: gez, you write one paper explaining how a lens is really</div>

<div>     a higher order monoidal natural transformation, and suddenly</div><div>     everyone thinks you are an expert on lenses.</div><div><br></div><div>   * roconnor: a lens is a monoidal natural transformation between</div>

<div>     higher-order coalgebra functors, what&#39;s the problem?</div><div><br></div><div>   * Enigmagic: we use the &#39;rsync&#39; deploy model</div><div><br></div><div>   * cmccann: someone should implement a dependently-typed unsafeCoerce</div>

<div>     in Agda, you&#39;d have to provide a proof that the coercion is invalid</div><div><br></div><div>   * ghc: Couldn&#39;t match type `No&#39; with `Yes&#39;</div><div><br></div><div>Top Reddit Stories</div><div><br>

</div><div>   * Idris - A language with dependent types</div><div>     Domain: <a href="http://idris-lang.org">idris-lang.org</a>, Score: 43, Comments: 30</div><div>     On Reddit: [1] <a href="http://goo.gl/pZdKX">http://goo.gl/pZdKX</a></div>

<div>     Original: [2] <a href="http://goo.gl/MxXKx">http://goo.gl/MxXKx</a></div><div><br></div><div>   * Purely Functional, Declarative Game Logic Using Reactive Programming</div><div>     Domain: <a href="http://github.com">github.com</a>, Score: 38, Comments: 17</div>

<div>     On Reddit: [3] <a href="http://goo.gl/ByPJj">http://goo.gl/ByPJj</a></div><div>     Original: [4] <a href="http://goo.gl/1PYa4">http://goo.gl/1PYa4</a></div><div><br></div><div>   * A guided tour through the bytestring library</div>

<div>     Domain: <a href="http://meiersi.github.com">meiersi.github.com</a>, Score: 32, Comments: 10</div><div>     On Reddit: [5] <a href="http://goo.gl/0YUQ2">http://goo.gl/0YUQ2</a></div><div>     Original: [6] <a href="http://goo.gl/A2u2S">http://goo.gl/A2u2S</a></div>

<div><br></div><div>   * Comprehensions</div><div>     Domain: <a href="http://patternsinfp.wordpress.com">patternsinfp.wordpress.com</a>, Score: 26, Comments: 7</div><div>     On Reddit: [7] <a href="http://goo.gl/9Zv3F">http://goo.gl/9Zv3F</a></div>

<div>     Original: [8] <a href="http://goo.gl/SNA14">http://goo.gl/SNA14</a></div><div><br></div><div>   * Thinking of writing a tutorial series on FP and Haskell. Here&#39;s a demo.</div><div>     Domain: <a href="http://codingtales.com">codingtales.com</a>, Score: 24, Comments: 9</div>

<div>     On Reddit: [9] <a href="http://goo.gl/eU99Y">http://goo.gl/eU99Y</a></div><div>     Original: [10] <a href="http://goo.gl/1efUI">http://goo.gl/1efUI</a></div><div><br></div><div>   * UHC compiles Haskell to JavaScript. Web game using Haskell for Ludum Dare?</div>

<div>     Domain: <a href="http://chrisdone.com">chrisdone.com</a>, Score: 23, Comments: 4</div><div>     On Reddit: [11] <a href="http://goo.gl/og088">http://goo.gl/og088</a></div><div>     Original: [12] <a href="http://goo.gl/8Op3M">http://goo.gl/8Op3M</a></div>

<div><br></div><div>   * Warp Conduits Released!</div><div>     Domain: <a href="http://yesodweb.com">yesodweb.com</a>, Score: 22, Comments: 3</div><div>     On Reddit: [13] <a href="http://goo.gl/zpHnZ">http://goo.gl/zpHnZ</a></div>

<div>     Original: [14] <a href="http://goo.gl/5Vl3w">http://goo.gl/5Vl3w</a></div><div><br></div><div>   * Why are guards in the list comprehension faster than in the do-notation?</div><div>     Domain: self.haskell, Score: 19, Comments: 22</div>

<div>     On Reddit: [15] <a href="http://goo.gl/1T8Kk">http://goo.gl/1T8Kk</a></div><div>     Original: [16] <a href="http://goo.gl/1T8Kk">http://goo.gl/1T8Kk</a></div><div><br></div><div>   * Hac Boston</div><div>     Domain: self.haskell, Score: 19, Comments: 7</div>

<div>     On Reddit: [17] <a href="http://goo.gl/xWWZF">http://goo.gl/xWWZF</a></div><div>     Original: [18] <a href="http://goo.gl/xWWZF">http://goo.gl/xWWZF</a></div><div><br></div><div>   * Easy steps to install gtk and use all its features on OS X lion</div>

<div>     Domain: <a href="http://gist.github.com">gist.github.com</a>, Score: 16, Comments: 10</div><div>     On Reddit: [19] <a href="http://goo.gl/Teh6P">http://goo.gl/Teh6P</a></div><div>     Original: [20] <a href="http://goo.gl/Su6Y1">http://goo.gl/Su6Y1</a></div>

<div><br></div><div>Top StackOverflow Questions</div><div><br></div><div>   * What is this haskell syntax?</div><div>     votes: 19, answers: 1</div><div>     Read on SO: [21] <a href="http://goo.gl/JCYg0">http://goo.gl/JCYg0</a></div>

<div><br></div><div>   * Why is the type of this function (a -&gt; a) -&gt; a?</div><div>     votes: 18, answers: 4</div><div>     Read on SO: [22] <a href="http://goo.gl/BTr8e">http://goo.gl/BTr8e</a></div><div><br></div>

<div>   * `Integer` vs `Int64` vs `Word64`</div><div>     votes: 13, answers: 1</div><div>     Read on SO: [23] <a href="http://goo.gl/Pc2CX">http://goo.gl/Pc2CX</a></div><div><br></div><div>   * Did I just write a continuation?</div>

<div>     votes: 12, answers: 1</div><div>     Read on SO: [24] <a href="http://goo.gl/aXnTw">http://goo.gl/aXnTw</a></div><div><br></div><div>   * How lazy is Haskell&#39;s `++`?</div><div>     votes: 12, answers: 3</div>

<div>     Read on SO: [25] <a href="http://goo.gl/GxPxC">http://goo.gl/GxPxC</a></div><div><br></div><div>   * Can Haskell be used to write shell scripts?</div><div>     votes: 12, answers: 4</div><div>     Read on SO: [26] <a href="http://goo.gl/u3Qke">http://goo.gl/u3Qke</a></div>

<div><br></div><div>   * Why does this Haskell code compile?</div><div>     votes: 12, answers: 2</div><div>     Read on SO: [27] <a href="http://goo.gl/yz6VB">http://goo.gl/yz6VB</a></div><div><br></div><div>   * Any nice tools for untying knots in Haskell?</div>

<div>     votes: 11, answers: 4</div><div>     Read on SO: [28] <a href="http://goo.gl/YGNeq">http://goo.gl/YGNeq</a></div><div><br></div><div>   * Two-dimensional zipper</div><div>     votes: 10, answers: 2</div><div>     Read on SO: [29] <a href="http://goo.gl/37E9J">http://goo.gl/37E9J</a></div>

<div><br></div><div>   * the way merge-sort faster than insertion-sort puzzles me</div><div>     votes: 10, answers: 2</div><div>     Read on SO: [30] <a href="http://goo.gl/mkmdc">http://goo.gl/mkmdc</a></div><div><br></div>

<div>   * Haskell function that takes a type and a value and checks if value has that type</div><div>     votes: 10, answers: 1</div><div>     Read on SO: [31] <a href="http://goo.gl/tJO81">http://goo.gl/tJO81</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://idris-lang.org/">http://idris-lang.org/</a></div><div>   2. <a href="http://www.reddit.com/r/haskell/comments/ol90m/idris_a_language_with_dependent_types/">http://www.reddit.com/r/haskell/comments/ol90m/idris_a_language_with_dependent_types/</a></div>

<div>   3. <a href="https://github.com/leonidas/codeblog/blob/master/2012/2012-01-17-declarative-game-logic-afrp.md">https://github.com/leonidas/codeblog/blob/master/2012/2012-01-17-declarative-game-logic-afrp.md</a></div>

<div>   4. <a href="http://www.reddit.com/r/haskell/comments/ol7vm/purely_functional_declarative_game_logic_using/">http://www.reddit.com/r/haskell/comments/ol7vm/purely_functional_declarative_game_logic_using/</a></div>
<div>
   5. <a href="http://meiersi.github.com/HaskellerZ/meetups/2012%2001%2019%20-%20The%20bytestring%20library/slides.html">http://meiersi.github.com/HaskellerZ/meetups/2012%2001%2019%20-%20The%20bytestring%20library/slides.html</a></div>

<div>   6. <a href="http://www.reddit.com/r/haskell/comments/oqjhy/a_guided_tour_through_the_bytestring_library/">http://www.reddit.com/r/haskell/comments/oqjhy/a_guided_tour_through_the_bytestring_library/</a></div><div>

   7. <a href="http://patternsinfp.wordpress.com/2012/01/19/comprehensions/">http://patternsinfp.wordpress.com/2012/01/19/comprehensions/</a></div><div>   8. <a href="http://www.reddit.com/r/haskell/comments/on8a6/comprehensions/">http://www.reddit.com/r/haskell/comments/on8a6/comprehensions/</a></div>

<div>   9. <a href="http://codingtales.com/2012/01/16/understanding-foldl-using-foldr-from-real-world-haskell/">http://codingtales.com/2012/01/16/understanding-foldl-using-foldr-from-real-world-haskell/</a></div><div>  10. <a href="http://www.reddit.com/r/haskell/comments/oi4l2/thinking_of_writing_a_tutorial_series_on_fp_and/">http://www.reddit.com/r/haskell/comments/oi4l2/thinking_of_writing_a_tutorial_series_on_fp_and/</a></div>

<div>  11. <a href="http://chrisdone.com/posts/2012-01-06-uhc-javascript.html">http://chrisdone.com/posts/2012-01-06-uhc-javascript.html</a></div><div>  12. <a href="http://www.reddit.com/r/haskell/comments/olthb/uhc_compiles_haskell_to_javascript_web_game_using/">http://www.reddit.com/r/haskell/comments/olthb/uhc_compiles_haskell_to_javascript_web_game_using/</a></div>

<div>  13. <a href="http://www.yesodweb.com/blog/2012/01/warp-conduits">http://www.yesodweb.com/blog/2012/01/warp-conduits</a></div><div>  14. <a href="http://www.reddit.com/r/haskell/comments/on285/warp_conduits_released/">http://www.reddit.com/r/haskell/comments/on285/warp_conduits_released/</a></div>

<div>  15. <a href="http://www.reddit.com/r/haskell/comments/oolyt/why_are_guards_in_the_list_comprehension_faster/">http://www.reddit.com/r/haskell/comments/oolyt/why_are_guards_in_the_list_comprehension_faster/</a></div>

<div>  16. <a href="http://www.reddit.com/r/haskell/comments/oolyt/why_are_guards_in_the_list_comprehension_faster/">http://www.reddit.com/r/haskell/comments/oolyt/why_are_guards_in_the_list_comprehension_faster/</a></div>

<div>  17. <a href="http://www.reddit.com/r/haskell/comments/opgi1/hac_boston/">http://www.reddit.com/r/haskell/comments/opgi1/hac_boston/</a></div><div>  18. <a href="http://www.reddit.com/r/haskell/comments/opgi1/hac_boston/">http://www.reddit.com/r/haskell/comments/opgi1/hac_boston/</a></div>

<div>  19. <a href="https://gist.github.com/1655271">https://gist.github.com/1655271</a></div><div>  20. <a href="http://www.reddit.com/r/haskell/comments/or0ro/easy_steps_to_install_gtk_and_use_all_its/">http://www.reddit.com/r/haskell/comments/or0ro/easy_steps_to_install_gtk_and_use_all_its/</a></div>

<div>  21. <a href="http://stackoverflow.com/questions/8905178/what-is-this-haskell-syntax">http://stackoverflow.com/questions/8905178/what-is-this-haskell-syntax</a></div><div>  22. <a href="http://stackoverflow.com/questions/8918990/why-is-the-type-of-this-function-a-a-a">http://stackoverflow.com/questions/8918990/why-is-the-type-of-this-function-a-a-a</a></div>

<div>  23. <a href="http://stackoverflow.com/questions/8873000/integer-vs-int64-vs-word64">http://stackoverflow.com/questions/8873000/integer-vs-int64-vs-word64</a></div><div>  24. <a href="http://stackoverflow.com/questions/8867837/did-i-just-write-a-continuation">http://stackoverflow.com/questions/8867837/did-i-just-write-a-continuation</a></div>

<div>  25. <a href="http://stackoverflow.com/questions/8872714/how-lazy-is-haskells">http://stackoverflow.com/questions/8872714/how-lazy-is-haskells</a></div><div>  26. <a href="http://stackoverflow.com/questions/8925780/can-haskell-be-used-to-write-shell-scripts">http://stackoverflow.com/questions/8925780/can-haskell-be-used-to-write-shell-scripts</a></div>

<div>  27. <a href="http://stackoverflow.com/questions/8935568/why-does-this-haskell-code-compile">http://stackoverflow.com/questions/8935568/why-does-this-haskell-code-compile</a></div><div>  28. <a href="http://stackoverflow.com/questions/8945096/any-nice-tools-for-untying-knots-in-haskell">http://stackoverflow.com/questions/8945096/any-nice-tools-for-untying-knots-in-haskell</a></div>

<div>  29. <a href="http://stackoverflow.com/questions/8905030/two-dimensional-zipper">http://stackoverflow.com/questions/8905030/two-dimensional-zipper</a></div><div>  30. <a href="http://stackoverflow.com/questions/8919785/the-way-merge-sort-faster-than-insertion-sort-puzzles-me">http://stackoverflow.com/questions/8919785/the-way-merge-sort-faster-than-insertion-sort-puzzles-me</a></div>

<div>  31. <a href="http://stackoverflow.com/questions/8957601/haskell-function-that-takes-a-type-and-a-value-and-checks-if-value-has-that-type">http://stackoverflow.com/questions/8957601/haskell-function-that-takes-a-type-and-a-value-and-checks-if-value-has-that-type</a></div>

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