http://osfameron.vox.com/library/posts/tags/haskell/page/1/ en Vox Fri, 20 Jun 2008 08:32:16 +0100 Copyright 2008 http://blogs.law.harvard.edu/tech/rss haskell http://osfameron.vox.com/library/post/more-countdown-laziness-scheme-and-german-frogs.html?_c=feed-rss nobody@vox.com(osfameron) http://osfameron.vox.com/library/post/more-countdown-laziness-scheme-and-german-frogs.html?_c=feed-rss http://osfameron.vox.com/library/post/more-countdown-laziness-scheme-and-german-frogs.html?_c=feed-rss Fri, 20 Jun 2008 08:32:16 +0100 The Countdown code I showed you isn't really taking advantage of Haskell's laziness. We should only have to check entries up until the point that we have enough matches (in the current code 'take 4 $ getAnagrams') and that's good. However, we ha... <p style="clear:both;"> <a href="http://osfameron.vox.com/library/post/more-countdown-laziness-scheme-and-german-frogs.html?_c=feed-rss#comments">Read and post comments</a> | <a href="http://www.vox.com/share/6a00c225240a9af21900fa9680035a0002?_c=feed-rss">Send to a friend</a> </p> countdown haskell scheme http://osfameron.vox.com/library/post/schwartzian-transform-in-haskell.html?_c=feed-rss nobody@vox.com(osfameron) http://osfameron.vox.com/library/post/schwartzian-transform-in-haskell.html?_c=feed-rss http://osfameron.vox.com/library/post/schwartzian-transform-in-haskell.html?_c=feed-rss Wed, 18 Jun 2008 22:53:28 +0100 In the last post, I mentioned that we might be able to improve the performance of our sort using a "http://en.wikipedia.org/wiki/Schwartzian_transform". This basically involves precaching the expensive calculation (in this case, length), sorti... <p style="clear:both;"> <a href="http://osfameron.vox.com/library/post/schwartzian-transform-in-haskell.html?_c=feed-rss#comments">Read and post comments</a> | <a href="http://www.vox.com/share/6a00c225240a9af21900fa967f97ec0002?_c=feed-rss">Send to a friend</a> </p> perl haskell http://osfameron.vox.com/library/post/countdown-words-game-solver-in-haskell.html?_c=feed-rss nobody@vox.com(osfameron) http://osfameron.vox.com/library/post/countdown-words-game-solver-in-haskell.html?_c=feed-rss http://osfameron.vox.com/library/post/countdown-words-game-solver-in-haskell.html?_c=feed-rss Wed, 18 Jun 2008 13:02:12 +0100 Will on #geekup has been working on a Countdown letters and numbers game solver written in Python. I thought it'd be fun to try to do it in Haskell, and started with the letters game (anagram) solver. Starting with a string of jumbled letters,... <p style="clear:both;"> <a href="http://osfameron.vox.com/library/post/countdown-words-game-solver-in-haskell.html?_c=feed-rss#comments">Read and post comments</a> | <a href="http://www.vox.com/share/6a00c225240a9af21900fa968015b70003?_c=feed-rss">Send to a friend</a> </p> countdown haskell http://osfameron.vox.com/library/post/monads-in-perl-take-1.html?_c=feed-rss nobody@vox.com(osfameron) http://osfameron.vox.com/library/post/monads-in-perl-take-1.html?_c=feed-rss http://osfameron.vox.com/library/post/monads-in-perl-take-1.html?_c=feed-rss Thu, 12 Jun 2008 23:27:26 +0100 <p class="enclosed-assets" style="margin-bottom: 10px;"> <a href="http://osfameron.vox.com/library/photo/6a00c225240a9af21900fae8c2562a000b.html?_c=feed-rss" style="float:left; margin-right:6px;"><img src="http://a2.vox.com/6a00c225240a9af21900fae8c2562a000b-50si" alt="Chain of lambdas?" /></a> <a href="http://osfameron.vox.com/library/photo/6a00c225240a9af21900fa967dc4a50002.html?_c=feed-rss" style="float:left; margin-right:6px;"><img src="http://a5.vox.com/6a00c225240a9af21900fa967dc4a50002-50si" alt="Nest of lambdas" /></a> <br style="clear:both;" /> </p> I've been away for a while from Haskell so I thought I should do some revision and really get my head around Monads. While I plodded through the wonderful "meet the monads" tutorial, I decided that the best way to learn would be to do. By implem... <p style="clear:both;"> <a href="http://osfameron.vox.com/library/post/monads-in-perl-take-1.html?_c=feed-rss#comments">Read and post comments</a> | <a href="http://www.vox.com/share/6a00c225240a9af21900fad690d9cd0004?_c=feed-rss">Send to a friend</a> </p> perl haskell monads lambdacamel http://osfameron.vox.com/library/post/f-talk-in-liverpool.html?_c=feed-rss nobody@vox.com(osfameron) http://osfameron.vox.com/library/post/f-talk-in-liverpool.html?_c=feed-rss http://osfameron.vox.com/library/post/f-talk-in-liverpool.html?_c=feed-rss Fri, 16 May 2008 08:35:07 +0100 <p class="enclosed-assets" style="margin-bottom: 10px;"> <a href="http://osfameron.vox.com/library/book/6a00c225240a9af21900fa9675da910003.html?_c=feed-rss" style="float:left; margin-right:6px;"><img src="http://a1.vox.com/6a00c225240a9af21900fa9675da910003-50si" alt="Expert F# Hardback (Expert&#39;s Voice in .Net)" /></a> <br style="clear:both;" /> </p> I'd been out of Liverpool for 3 years or so, and I completely missed GeekUp: a loosely affiliated, grassroots tech meetup society in the North West. The Liverpool branch is pretty active, and linked with various other groups, such as the DotNet ... <p style="clear:both;"> <a href="http://osfameron.vox.com/library/post/f-talk-in-liverpool.html?_c=feed-rss#comments">Read and post comments</a> | <a href="http://www.vox.com/share/6a00c225240a9af21900fad6884a750004?_c=feed-rss">Send to a friend</a> </p> dotnet mono liverpool geekup haskell f# ocaml erlang monads http://osfameron.vox.com/library/post/monad-wars---code-online.html?_c=feed-rss nobody@vox.com(osfameron) http://osfameron.vox.com/library/post/monad-wars---code-online.html?_c=feed-rss http://osfameron.vox.com/library/post/monad-wars---code-online.html?_c=feed-rss Wed, 28 Nov 2007 09:19:59 +0000 Chessguy pointed out that it's currently hard to play along with the monad wars code. It would be nice for the posts to be “literate haskell”, where sections preceded by “>“ characters are valid Haskell. The idea is great - that you can mix secti... <p style="clear:both;"> <a href="http://osfameron.vox.com/library/post/monad-wars---code-online.html?_c=feed-rss#comments">Read and post comments</a> | <a href="http://www.vox.com/share/6a00c225240a9af21900e398c1eda80002?_c=feed-rss">Send to a friend</a> </p> haskell monadwars http://osfameron.vox.com/library/post/monad-wars---3-command-line-actions.html?_c=feed-rss nobody@vox.com(osfameron) http://osfameron.vox.com/library/post/monad-wars---3-command-line-actions.html?_c=feed-rss http://osfameron.vox.com/library/post/monad-wars---3-command-line-actions.html?_c=feed-rss Tue, 27 Nov 2007 07:52:19 +0000 After the last post, we have parser actions that can recognise an integer or an item of merchandise. Now we need to be able to process a command, like “jet bronx” or “buy 4 lambdas”. Let's start off with this basis: > parseCommand = parseMap co... <p style="clear:both;"> <a href="http://osfameron.vox.com/library/post/monad-wars---3-command-line-actions.html?_c=feed-rss#comments">Read and post comments</a> | <a href="http://www.vox.com/share/6a00c225240a9af21900e398c18f130001?_c=feed-rss">Send to a friend</a> </p> haskell monadswars http://osfameron.vox.com/library/post/monad-wars---25-some-comments-and-corrections.html?_c=feed-rss nobody@vox.com(osfameron) http://osfameron.vox.com/library/post/monad-wars---25-some-comments-and-corrections.html?_c=feed-rss http://osfameron.vox.com/library/post/monad-wars---25-some-comments-and-corrections.html?_c=feed-rss Tue, 27 Nov 2007 07:50:45 +0000 One of the advantages of demonstrating your ignorance in public is that you may receive useful corrections... thanks to everyone who replied on these recent posts, I found the comments very instructive, and thought it was worth writing up as a ne... <p style="clear:both;"> <a href="http://osfameron.vox.com/library/post/monad-wars---25-some-comments-and-corrections.html?_c=feed-rss#comments">Read and post comments</a> | <a href="http://www.vox.com/share/6a00c225240a9af21900e398c18ef50001?_c=feed-rss">Send to a friend</a> </p> haskell monadwars http://osfameron.vox.com/library/post/monad-wars---2-the-command-line.html?_c=feed-rss nobody@vox.com(osfameron) http://osfameron.vox.com/library/post/monad-wars---2-the-command-line.html?_c=feed-rss http://osfameron.vox.com/library/post/monad-wars---2-the-command-line.html?_c=feed-rss Mon, 26 Nov 2007 08:46:32 +0000 This time around, we're going to look at how we'll turn user input into commands in Monad Wars. I think that the easiest option to implement will also be very convenient to play with: a command line where we issue commands like: $ buy 4 foo $ ... <p style="clear:both;"> <a href="http://osfameron.vox.com/library/post/monad-wars---2-the-command-line.html?_c=feed-rss#comments">Read and post comments</a> | <a href="http://www.vox.com/share/6a00c225240a9af21900e398c138300001?_c=feed-rss">Send to a friend</a> </p> haskell monadwars http://osfameron.vox.com/library/post/monad-wars---1-the-prompt.html?_c=feed-rss nobody@vox.com(osfameron) http://osfameron.vox.com/library/post/monad-wars---1-the-prompt.html?_c=feed-rss http://osfameron.vox.com/library/post/monad-wars---1-the-prompt.html?_c=feed-rss Fri, 23 Nov 2007 13:22:27 +0000 A lot of learning projects involve writing games: people have written clones of Tetris, Asteroids, Space Invaders, and even first person shooters (Frag) in Haskell. As I'm far less clever than these people, I thought I'd start with something a bi... <p style="clear:both;"> <a href="http://osfameron.vox.com/library/post/monad-wars---1-the-prompt.html?_c=feed-rss#comments">Read and post comments</a> | <a href="http://www.vox.com/share/6a00c225240a9af21900e398c069580005?_c=feed-rss">Send to a friend</a> </p> haskell monadwars