Can an Akka anonymous actor have access to self? In my particular case I'm wondering if I can reply back to the sender with code similar to this (does not compile due to self not being found): val xmlLoader = Actor.init { println("xml loader started") } receive { case LoadResource(url) => { try { val xml = XM...
Hi guys! I'm currently developing a web application using PHP, but I'm considering developing the web application using the lift framework instead, because twitter and foursquare have implemented it. I know a few benefits using lift/Scala but, could you guys mention some benefits compared to PHP? Many thanks ...
I've got a two dimensional array and I want to apply a function to each value in the array. Here's what I'm working with: scala> val array = Array.tabulate(2,2)((x,y) => (0,0)) array: Array[Array[(Int, Int)]] = Array(Array((0,0), (0,0)), Array((0,0), (0,0))) I'm using foreach to extract the tuples: scala> array.foreach(i => i.foreac...
Hi Folks, I've got a list of objects List[Object] which are all instantiated from the same class. This class has a field which must be unique Object.property. What is the cleanest way to iterate the list of objects and remove all objects(but the first) with the same property? Cheers Parsa ...
I saw a below code: Map(1 -> "one", 2 -> "two") map _._1 this return a Iterable[Int], but if I want to do nothing with map, how to do it? I want to do something like below, but the below code can't compile, I know because it a object instance not a function, but how to create a function to do x => x and use placeholder: Map(1 -> "on...
Is it a bug in Scala 2.8.0 ? (the same happens with 2.8.1.RC2) import junit.framework._ import Assert._ class BugTest extends TestCase { def compare(first: Any, second: Any): Int = { (first, second) match { case (k: Int, o: Int) => k compare o //why the next case matches (Float, Int) but does not match (Int, F...
Hi, since normal operators like +, ::, -> and so on are all methods which can be overloaded and stuff I was wondering if || and && are methods as well. This could theoretically work if this were methods in of the boolean object. But if they are, why is something like if (foo == bar && buz == fol) possible? If the compiler reads from ...
I want to do something like this (simplified quite heavily): ((1, 2, 3, 4, 5, 6), (6, 5, 4, 3, 2, 1)).zipped map (_ + _) Ignore the actual values of the integers (although it's important that these are 6-tuples, actually :)). Essentially, I want to use this fairly regularly in a function which maintains a Map[String, (Int, Int, Int, ...
Hello, I'd like to write a type alias to shorten, nice and encapsulated Scala code. Suppose I got some collection which has the property of being a list of maps, the value of which are tuples. My type would write something like List[Map[Int, (String, String)]], or anything more generic as my application allows it. I could imagine having...
I would like to parameterize a type with one of its subclasses. Consider the following: class DataLoader { class Data { /* data specifics to this data loader */ } def getData : Data /* and so on */ } Now I want to make this loader able to asynchronously retrieve data from the network. One of the options is to have it subclass Call...
Hey folks, Title is pretty self-explanatory. How can I convert an instance of org.w3c.dom.Document to a Scala NodeSeq, to enjoy it's facilitation? Cheers Parsa ...
I have approx. 6000 PNG files (256*256 pixels) and want to combine them into a big PNG holding all of them programmatically. What's the best/fastest way to do that? (The purpose is printing on paper, so using some web-technology is not an option and having one, single picture file will eliminate many usage errors.) I tried fahd's sugg...
What are the most commonly held misconceptions about the Scala language, and what counter-examples exist to these? UPDATE I was thinking more about various claims I've seen, such as "Scala is dynamically typed" and "Scala is a scripting language". I accept that "Scala is [Simple/Complex]" might be considered a myth, but it's also a vi...
Welcome to Scala version 2.8.0.Beta1-prerelease (Java HotSpot(TM) Client VM, Java 1.6.0_21). Type in expressions to have them evaluated. Type :help for more information. scala> List(3, 1, 2).sorted <console>:5: error: value sorted is not a member of List[Int] List(3, 1, 2).sorted ^ Why am I getting this wei...
I am struggling to find any decent links to design patterns, best practice or good, basic architectural principles that should be used in building Actor-based apps. Those few that I know of are: Blog posts, articles, WIKIs, guides OTP Design Principles User's Guide Patterns and Best Practices for Enterprise Integration (in general, c...
I'm trying to define a generic residue class ring in Scala. A residue class ring is defined by some base ring (e.g. the integers) and a modulus (e.g. two), which is a value from the base ring. Both rings and their elements are objects, hence the type of the modulus would normally be a dependent type, depending on the base ring. I underst...
Is there something similar to slice notation in python in scala ? I think this is really a useful operation that should be incorporated in all languages. ...
Hello I want to generate PHP-code from a Model I created from parsing a WSDL-File. Anyone an advice how to generate PHP-Code in a smart way? Thanks ...
I came across this really nice looking Scala code while researching XMPP for a .Net project we're working on: object Main { /** * @param args the command line arguments */ def main(args: Array[String]) :Unit = { new XMPPComponent( new ComponentConfig() { def secret() : String = { "secret.goes.here" ...
A lot of sample Scala code contains Strings and Collections named "xs" Why xs? Anything to do with the xs: used in XML (for Schema?) Examples: var xs = List(1,2,3) val xs = "abc" ...