å æ¥ã®ãReactive System Meetup in 西æ°å®¿ãã§ãScalaz-Streamã«ããFunctional Reactive Programmingãã®ã¹ã©ã¤ããä½ãã«ããã£ã¦scalazã®Taskã«ã¤ãã¦èª¿ã¹ãªããã¦ã¿ãã®ã§ãããTaskã®å®ç¨æ§ã«ã¤ãã¦å確èªãããã¨ãã§ãã¾ããã è²ã ã¨åãå£ãããã¾ããããã®ä¸ã§ä¸¦åæ§è½ãä»åã®ãã¼ãã§ãã æºåæºåã¨ãã¦ä»¥ä¸ã®ãã®ãç¨æãã¾ãã implicit val scheduler = new java.util.concurrent.ForkJoinPool(1000) def go[T](msg: String)(body: => T): Unit = { System.gc val ts = System.currentTimeMillis val r = body println(s"$msg(${System.c
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Scalaz used to have a scalaz.Functor for scala.collection.Set but it was eventually removed because it relied on Anyâs == method. You can read more about why Functor[Set] is a bad idea at Fake Theorems for Free. If Set had been truly parametric, we wouldnât have been able to define a Functor in the first place. Luckily, a truly parametric Set has recently been added to Scalaz as scalaz.ISet, with
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æ¸ç±ã ãããHaskellãã®ããå¦ã¼ã! ã ã® Ordering ã¢ãã¤ãã使ã£ã lengthCompare é¢æ°ã Scalaz ã§å®è£ ãã¦ã¿ã¾ããã Scalaz 7.0.0-M3 sbt 0.12.0 ãµã³ãã«ã½ã¼ã¹ã¯ http://github.com/fits/try_samples/tree/master/blog/20120828/ lengthCompare é¢æ°ã¯ä»¥ä¸ã®ããã«æååãæ¯è¼ããåã«æååé·ãæ¯è¼ããã¨ãããã®ã§ãæååé·ãçããã£ãå ´åã®ã¿ ï¼= EQï¼ æååã®æ¯è¼ ï¼`mappend` ã®å³è¾ºï¼ ãå®æ½ãã¾ããï¼å¦çå 容ã¯æ¬ã®ã¾ã¾ã§ãï¼ Haskellç length_compare.hs import Data.Monoid lengthCompare :: String -> String -> Ordering lengthCompare
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scalaz ã® ExampleState ã« StateT ã®ãµã³ãã«ãç¡ãã£ãã®ã§è©¦ãã¦ã¿ãã æ°ãåãããããããã State ã¢ããã£ã¦ä½ãï¼ã¨ããæãã説ææ¸ãããã package com.github.cooldaemon.try_scalaz import scalaz._ object TryState { import Scalaz._ def run { def initO = stateT[Option, Int, Int]((s: Int) => if (s % 2 == 0) Some((s, s)) else None ) initO ! 1 assert_=== None initO ! 2 assert_=== Some(2) def putO(s: Int) = stateT[Option, Int, Unit](_ => if (s % 2 == 0
NOTE: This content is being moved to the target of this link. Please update your bookmarks. Scalaz 5.0 adds an implementation of a concept called Iteratee. This is a highly flexible programming technique for writing enumeration-based input processors that can be freely composed. A lot of people have asked me to write a tutorial on how this works, specifically on how it is implemented in Scalaz and
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