In Scala you can use scala.util.Random: util.Random.shuffle((1 to 10).toSeq) //Vector(9, 6, 8, 7, 10, 1, 2, 5, 3, 4) util.Random.shuffle(List(‘A’, ‘B’, ‘C’, ‘D’, ‘E’, ‘F’)) //List(B, D, A, E, C, F) Your results may vary…
You can get env variables with the commands mentioned other responses like: sys.env.get(“USERNAME”) sys.env.get(“PASSWORD”) but they return an option of type Option[String] To turn this into string you need to either do a match or simply use sys.env.get(“USERNAME”).get sys.env.get(“USERNAME”).getOrElse(“some default value”) if you need to set some default value. Warning! calling .get of an option … Read more
Indeed – I also find it pretty confusing! Here’s a problem where I have some property which may be a parseable date: def parse(s: String) : Date = new SimpleDateFormat(“yyyy-MM-dd”).parse(s) def parseDate = parse(System.getProperty(“foo.bar”)) type PE = ParseException import scala.util.control.Exception._ val d1 = try { parseDate } catch { case e: PE => new Date … Read more
Here is my rationalization: classOf[T] classOf is defined in Predef as a function with this signature: def classOf[T]: Class[T] Although it’s implemented by the compiler, using the function syntax is possible without having to create any special treatment in terms of syntax. So that’s one reason here to consider this option. The alternative like String.class … Read more
The short answer is that right-associativity can improve readability by making what the programmer type consistent with what the program actually does. So, if you type ‘1 :: 2 :: 3‘, you get a List(1, 2, 3) back, instead of getting a List back in a completely different order. That would be because ‘1 :: … Read more
Your argument is flawed. Kotlin has not been released yet*, and Ceylon just had its first version released, and I’ll quote one of the things it is missing from their announcement: reified generics So, excuse me, but what implementation proves it is possible? In fact, I haven’t looked much at what Kotlin is promising, but … Read more
One of the notable things about SQLAlchemy is that it makes tables first class objects. Thus the core API is really written around table objects, and the API therefore is essentially relational in nature. Thus at this level even if the API is OO, it is essentially reflecting RDBMS objects or functions such as Tables, … Read more
adding the Scala dependency to the maven build can fix the issue : <dependency> <groupId>org.scala-lang</groupId> <artifactId>scala-library</artifactId> <version>2.10.3</version> </dependency>
You can use :reset Welcome to Scala version 2.10.0-RC2 (Java HotSpot(TM) 64-Bit Server VM, Java 1.6.0_37). Type in expressions to have them evaluated. Type :help for more information. scala> val a = 1 a: Int = 1 scala> val b = 3 b: Int = 3 scala> :reset Resetting interpreter state. Forgetting this session history: … Read more
consoleQuick is an SBT task that starts a REPL with the same classpath as console but without forcing compilation. (It is described alongside similar tasks by the sbt tasks command).