scala-2.8

What kind of constructs need 'scalac' compile and how to make an equivalent that will work in interpreter? Edit: I want to use scala instead of python as a scripting language. (with #!/usr/bin/scala) You ought to be able to do anything in the REPL that you can do in outside code. Keep in mind that: Things that refer to each other circularly need to be inside one block. So the following can't be entered as-is; you have to wrap it inside some other object: class C(i : Int) { def succ = C(i+1) } object C { def apply(i: Int) = new C(i) } The execution environment is somewhat different, so

@BeanProperty generates simple get / set methods. Is there a way to automatically generate such methods with support for firing property change events (e.g. I want to use it with JFace Databinding?) I've had the same question, and have been keeping a close eye out for possible answers. I think I've just stumbled across one (although I haven't tried it yet). Scala 2.9 has a feature for handling dynamic calls (meant for integration with dynamic languages, I suspect). Essentially, calls to methods which don't exist are routed to a method called applyDynamic. An implementation of that method could

I'm an 18 years old trainee and I'm discovering scala which I like very much :-). To get familiar with the scala actors I wrote a small simulation with some gears and one controller. The ActorApplication creates N gears with random speed. The controller calculates a synchronization speed and starts the gear-actors. The gears synchronize to this given speed step by step (1+ or 1-). The simulation is finished when all gears have reached the synchronization speed. I developed the simulation in scala 2.7.7 - and it worked as I expected it (see output below). However, when I swichted to the current

I'm trying to reduce the extent to which I write Scala (2.8) like Java. Here's a simplification of a problem I came across. Can you suggest improvements on my solutions that are "more functional"? Transform the map val inputMap = mutable.LinkedHashMap(1->'a',2->'a',3->'b',4->'z',5->'c') by discarding any entries with value 'z' and indexing the characters as they are encountered First try var outputMap = new mutable.HashMap[Char,Int]() var counter = 0 for(kvp <- inputMap){ val character = kvp._2 if(character !='z' && !outputMap.contains(character)){ outputMap += (character -> counter) counter +

I'm looking to create a document like this: <root/> That I can add children to programatically. Theoretically, it would look like this: val root_node_name = "root" val doc = <{root_node_name}/> But that doesn't seem to work: error: not found: value < So, what I tried instead was this: val root_node_name = "root" val doc = new scala.xml.Elem(null, root_node_name, null, scala.xml.TopScope, null) That compiles but at runtime I get this null pointer exception: java.lang.NullPointerException at scala.xml.Utility$.toXML(Utility.scala:201) at scala.xml.Utility$$anonfun$sequenceToXML$2.apply(Utility

Making a migration from 2.8.1 to 2.9.1 found interesting thing. Tried to write this in console: >>import collection.immutable.Set.Set4 >>new Set4[Int](1,2,3,4) It gives: java.lang.Error: Unexpected New at scala.tools.nsc.symtab.SymbolTable.abort(SymbolTable.scala:34) at scala.tools.nsc.backend.icode.GenICode$ICodePhase.scala$tools$nsc$bac .......................... That entry seems to have slain the compiler. Shall I replayscala:660) your session? I can re-run each line except the last one.reach(ListBuffer.scala: [y/n]? I am using Scala version 2.9.1.final (Java HotSpot(TM) Client VM, Java 1.6

Assume you have a List(1,"1") it is typed List[Any], which is of course correct and expected. Now if I map the list like this scala> List(1, "1") map { | case x: Int => x | case y: String => y.toInt | } the resulting type is List[Int] which is expected as well. My question is if there is an equivalent to map for filter because the following example will result in a List[Any]. Is this possible? I assume this could be solved at compile time and possibly not runtime? scala> List(1, "1") filter { | case x: Int => true | case _ => false | } Daniel C. Sobral Scala 2.9: scala> List(1, "1") collect {

OK, in the question about 'Class Variables as constants' , I get the fact that the constants are not available until after the 'official' constructor has been run (i.e. until you have an instance). BUT, what if I need the companion singleton to make calls on the class: object thing { val someConst = 42 def apply(x: Int) = new thing(x) } class thing(x: Int) { import thing.someConst val field = x * someConst override def toString = "val: " + field } If I create companion object first, the 'new thing(x)' (in the companion) causes an error. However, if I define the class first, the 'x * someConst'