Search Results

Search found 2945 results on 118 pages for 'scala designer'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 14/118 | < Previous Page | 10 11 12 13 14 15 16 17 18 19 20 21  | Next Page >

  • C++ vainqueur d'un benchmark avec Java, Scala et Go présenté aux Scala Days, l'étude portait sur l'implémentation d'un algorithme

    C++ vainqueur d'un benchmark avec Java, Scala et Go Présentée aux Scala Days, l'étude portait sur l'implémentation d'un algorithme Bonne nouvelle pour tous les amateurs de C++ ! Ce langage reste le plus performant et sans conteste ! Présenté au Scala Days en début de mois, un benchmark met en compétition le C++, Java, Scala et GO pour l'implémentation du même algorithme en cherchant à s'appuyer sur les éléments du langage (pas de Boost ici donc). Et C++ remporte haut la main en temps d'exécution mais aussi en empreinte mémoire. Mieux, contrairement à certaines idées reçues, les temps de compilation ou le nombre de ligne de code restent à des valeurs qui n'ont pas à rougir face à Java par exemple....

    Read the article

  • Does Scala's BigDecimal violate the equals/hashCode contract?

    - by oxbow_lakes
    As the Ordered trait demands, the equals method on Scala's BigDecimal class is consistent with the ordering. However, the hashcode is simply taken from the wrapped java.math.BigDecimal and is therefore inconsistent with equals. object DecTest { def main(args: Array[String]) { val d1 = BigDecimal("2") val d2 = BigDecimal("2.00") println(d1 == d2) //prints true println(d1.hashCode == d2.hashCode) //prints false } } I can't find any reference to this being a known issue. Am I missing something?

    Read the article

  • Variadic templates in Scala

    - by Thomas Jung
    Suppose you want to have something like variadic templates (the ability to define n type parameters for a generic class) in Scala. For example you do not want to define Tuple2[+T1, +T2] and Tuple3[+T1, +T2, +T3] but Tuple[T*]. Are there other options than HLists?

    Read the article

  • scala jpa notifying hibernate

    - by coubeatczech
    Hi, i just tried to play a little with Scala Jpa, Downladed and run the basic lift-jpa-basic maven archetype, it works, but when I try to add my own @Entity, there is Unknown entity exception thrown. So what do I need to tell the environment to notify my entities? Thanks for answering.

    Read the article

  • Scala compiler says unreachable code, why?

    - by taotree
    I'm new to Scala... Here's the code: def ack2(m: BigInt, n: BigInt): BigInt = { val z = BigInt(0) (m,n) match { case (z,_) => n+1 case (_,z) => ack2(m-1,1) // Compiler says unreachable code on the paren of ack2( case _ => ack2(m-1, ack2(m, n-1)) // Compiler says unreachable code on the paren of ack2( } } I'm trying to understand that... why is it giving that error?

    Read the article

  • Scala giving me "illegal start of definition"

    - by Malvolio
    I'm trying to get started with Scala and cannot get out of the starting gate. A file consisting of the line package x gives me error: illegal start of definition Regardless of what x is and regardless of where I put the file (I had a theory that I had to place the file in a directory hierarchy to match the package definition, but no). I get the same error with the example code from the web site and with the REPL.

    Read the article

  • scala currying by nested functions or by multiple parameter lists

    - by Morgan Creighton
    In Scala, I can define a function with two parameter lists. def myAdd(x :Int)(y :Int) = x + y This makes it easy to define a partially applied function. val plusFive = myAdd(5) _ But, I can accomplish something similar by defining and returning a nested function. def myOtherAdd(x :Int) = { def f(y :Int) = x + y f _ } Cosmetically, I've moved the underscore, but this still feels like currying. val otherPlusFive = myOtherAdd(5) What criteria should I use to prefer one approach over the other?

    Read the article

  • scala for yield setting a value

    - by coubeatczech
    Hi, I want to create a list of GridBagPanel.Constraints. I read it in the scala programming book, that there is a cool for-yield construction, but I probably haven't understood the way it works correctly, because my code doesn't compile. Here it is: val d = for { i <- 0 until 4 j <- 0 until 4 } yield { c = new Constraints c.gridx = j c.gridy = i } I want to generate a List[Constraints] and for every constraint set different x,y values so later, when I later add the components, they're going to be in a grid.

    Read the article

  • Ant-Ivy-Scala Template: any suggestions on improvements?

    - by luigi-prog
    I just created a template project for Scala using Ant and Apache Ivy. I want to get the communitie's input on any improvements to the Template so it can be improved. The Environment effectively consists of 3 files: build.xml ivy.xml ivysettings.xml running ant init will create all needed directories. I was wondering if there are any Ant or Apache Ivy gurus around that could give some input. The Git Project is Located Here And the Project HomePage here

    Read the article

  • What is the best scala-like persistence framework available right now?

    - by egervari
    What is the best scala-like persistence framework available right now? Hibernate works, but it's not very scala-like. It insists on using annotations, no-arg constructors, doesn't work with anonymous class instances, doesn't work with scala collections, has an outdated string-based query model, etc. I'm looking for something that really fits Scala. Does it exist? Or do I have to make it?

    Read the article

  • SBT run differences between scala and java?

    - by Eric Cartner
    I'm trying to follow the log4j2 configuration tutorials in a SBT 0.12.1 project. Here is my build.sbt: name := "Logging Test" version := "0.0" scalaVersion := "2.9.2" libraryDependencies ++= Seq( "org.apache.logging.log4j" % "log4j-api" % "2.0-beta3", "org.apache.logging.log4j" % "log4j-core" % "2.0-beta3" ) When I run the main() defined in src/main/scala/logtest/Foo.scala: package logtest import org.apache.logging.log4j.{Logger, LogManager} object Foo { private val logger = LogManager.getLogger(getClass()) def main(args: Array[String]) { logger.trace("Entering application.") val bar = new Bar() if (!bar.doIt()) logger.error("Didn't do it.") logger.trace("Exiting application.") } } I get the output I was expecting given that src/main/resources/log4j2.xml sets the root logging level to trace: [info] Running logtest.Foo 08:39:55.627 [run-main] TRACE logtest.Foo$ - Entering application. 08:39:55.630 [run-main] TRACE logtest.Bar - entry 08:39:55.630 [run-main] ERROR logtest.Bar - Did it again! 08:39:55.630 [run-main] TRACE logtest.Bar - exit with (false) 08:39:55.630 [run-main] ERROR logtest.Foo$ - Didn't do it. 08:39:55.630 [run-main] TRACE logtest.Foo$ - Exiting application. However, when I run the main() defined in src/main/java/logtest/LoggerTest.java: package logtest; import org.apache.logging.log4j.Logger; import org.apache.logging.log4j.LogManager; public class LoggerTest { private static Logger logger = LogManager.getLogger(LoggerTest.class.getName()); public static void main(String[] args) { logger.trace("Entering application."); Bar bar = new Bar(); if (!bar.doIt()) logger.error("Didn't do it."); logger.trace("Exiting application."); } } I get the output: [info] Running logtest.LoggerTest ERROR StatusLogger Unable to locate a logging implementation, using SimpleLogger ERROR Bar Did it again! ERROR LoggerTest Didn't do it. From what I can tell, ERROR StatusLogger Unable to ... is usually a sign that log4j-core is not on my classpath. The lack of TRACE messages seems to indicate that my log4j2.xml settings aren't on the classpath either. Why should there be any difference in classpath if I'm running Foo.main versus LoggerTest.main? Or is there something else causing this behavior? Update I used SBT Assembly to build a fat jar of this project and specified logtest.LoggerTest to be the main class. Running it from the command line produced correct results: Eric-Cartners-iMac:target ecartner$ java -jar "Logging Test-assembly-0.0.jar" 10:52:23.220 [main] TRACE logtest.LoggerTest - Entering application. 10:52:23.221 [main] TRACE logtest.Bar - entry 10:52:23.221 [main] ERROR logtest.Bar - Did it again! 10:52:23.221 [main] TRACE logtest.Bar - exit with (false) 10:52:23.221 [main] ERROR logtest.LoggerTest - Didn't do it. 10:52:23.221 [main] TRACE logtest.LoggerTest - Exiting application.

    Read the article

  • Thread pool in scala

    - by ghedas
    I have a project that is actor-based and for one part of it I must use some actors that receive message after that one actor assigns to each request separately and each actor is responsible for doing its message request, so I need something like a thread pool for actors of my project, are there any features in Scala that is useful for my necessity? how can I achieve this goal? tanks a lot for your attention!

    Read the article

  • scala actor message definition

    - by BenZen
    Do i need to define class for message i want to retrieve on a scala actor? i trying to get this up where am i wrong def act() { loop { react { case Meet = foundMeet = true ; goHome case Feromone(qty) if (foundMeet == true) = sender ! Feromone(qty+1); goHome }}}

    Read the article

  • Are Maybes a good pattern for scala?

    - by Fred Haslam
    For a while I have been struggling to integrate scala with java methods that might return null. I came up with the following utility which helps a lot: // produce an Option, nulls become None object Maybe { def apply[T](t:T) = if (t==null) None else Some(t) } Maybe(javaClass.getResultCouldBeNull()).map( result => doSomeWork(result) ) I have a few questions about this solution: Is there a better or more standard pattern to use? Am I duplicating something that already exists? Does this functionality have hidden gotchas?

    Read the article

  • Unpacking tuple types in Scala

    - by jpalecek
    I was just wondering, can I decompose a tuple type into its components' types in Scala? I mean, something like this trait Container { type Element } trait AssociativeContainer extends Container { type Element <: (Unit, Unit) def get(x : Element#First) : Element#Second }

    Read the article

  • Scala passing type parameters to object

    - by Shahzad Mian
    In Scala v 2.7.7 I have a file with class Something[T] extends Other { } object Something extends OtherConstructor[Something] { } This throws the error: class Something takes type parameters object Something extends OtherConstructor[Something] { However, I can't do this object Something[T] extends OtherConstructor[Something[T]] { } It throws an error: error: ';' expected but '[' found. Is it possible to send type parameters to object? Or should I change and simply use Otherconstructor

    Read the article

  • Create and populate two-dimensional array in Scala

    - by ~asteinlein
    What's the recommended way of creating a pre-populated two-dimensional array in Scala? I've got the following code: val map = for { x <- (1 to size).toList } yield for { y <- (1 to size).toList } yield (x, y) How do I make an array instead of list? Replacing .toList with .toArray doesn't compile. And is there a more concise or readable way of doing this than the nested for expressions?

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 10 11 12 13 14 15 16 17 18 19 20 21  | Next Page >