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• Assembly wide multicast attributes. Are they evil?

  - by HeavyWave

  I am working on a project where we have several attributes in AssemblyInfo.cs, that are being multicast to a methods of a particular class. [assembly: Repeatable( AspectPriority = 2, AttributeTargetAssemblies = "MyNamespace", AttributeTargetTypes = "MyNamespace.MyClass", AttributeTargetMemberAttributes = MulticastAttributes.Public, AttributeTargetMembers = "*Impl", Prefix = "Cls")] What I don't like about this, is that it puts a piece of login into AssemblyInfo (Info, mind you!), which for starters should not contain any logic at all. The worst part of it, is that the actual MyClass.cs does not have the attribute anywhere in the file, and it is completely unclear that methods of this class might have them. From my perspective it greatly hurts readability of the code (not to mention that overuse of PostSharp can make debugging a nightmare). Especially when you have multiple multicast attributes. What is the best practice here? Is anyone out there is using PostSharp attributes like this?

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• Good programming style when handling multiple objects

  - by Glitch

  I've been programming a software version of a board game. Thus far I have written the classes which will correspond to physical objects on the game board. I'm well into writing the program logic, however I've found that many of the logic classes require access to the same objects. At first I was passing the appropriate objects to methods as they were called, but this was getting very tedious, particularly when the methods required many objects to perform their tasks. To solve this, I created a class which initialises and stores all the objects I need. This allows me to access an object from any class by calling Assets.dice(), for example. But now that I've thought about it, this doesn't seem right. This is why I'm here, I fear that I've created some sort of god class. Is this fear unfounded, or have I created a recipe for disaster?

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• When defining a class as internal, do you define what would usually be public fields as internal?

  - by devoured elysium

  When defining a class as internal, do you define what would usually be public fields as internal? Or do you leave them as public? I have a set of classes with public/private methods that I have decided to set as internal. Now, should I change the class' modifier to internal and let the rest of the methods/properties as they are (public/private) or switch them to (internal/private)? I don't see a big point in changing it to internal, and if by some reason later I want to set them back to public it's going to give a lot of work to have to put them back to public again. Any other thoughts on this?

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• TransactionScope Prematurely Completed

  - by Chris

  I have a block of code that runs within a TransactionScope and within this block of code I make several calls to the DB. Selects, Updates, Creates, and Deletes, the whole gamut. When I execute my delete I execute it using an extension method of the SqlCommand that will automatically resubmit the query if it deadlocks as this query could potentially hit a deadlock. I believe the problem occurs when a deadlock is hit and the function tries to resubmit the query. This is the error I receive: The transaction associated with the current connection has completed but has not been disposed. The transaction must be disposed before the connection can be used to execute SQL statements. This is the simple code that executes the query (all of the code below executes within the using of the TransactionScope): using (sqlCommand.Connection = new SqlConnection(ConnectionStrings.App)) { sqlCommand.Connection.Open(); sqlCommand.ExecuteNonQueryWithDeadlockHandling(); } Here is the extension method that resubmits the deadlocked query: public static class SqlCommandExtender { private const int DEADLOCK_ERROR = 1205; private const int MAXIMUM_DEADLOCK_RETRIES = 5; private const int SLEEP_INCREMENT = 100; public static void ExecuteNonQueryWithDeadlockHandling(this SqlCommand sqlCommand) { int count = 0; SqlException deadlockException = null; do { if (count > 0) Thread.Sleep(count * SLEEP_INCREMENT); deadlockException = ExecuteNonQuery(sqlCommand); count++; } while (deadlockException != null && count < MAXIMUM_DEADLOCK_RETRIES); if (deadlockException != null) throw deadlockException; } private static SqlException ExecuteNonQuery(SqlCommand sqlCommand) { try { sqlCommand.ExecuteNonQuery(); } catch (SqlException exception) { if (exception.Number == DEADLOCK_ERROR) return exception; throw; } return null; } } The error occurs on the line that executes the nonquery: sqlCommand.ExecuteNonQuery();

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• How to implement buffering with timeout in RX

  - by Gaspar Nagy

  I need to implement an event processing, that is done delayed when there are no new events arriving for a certain period. (I have to queue up a parsing task when the text buffer changed, but I don't want to start the parsing when the user is still typing.) I'm new in RX, but as far as I see, I would need a combination of BufferWithTime and the Timeout methods. I imagine this to be working like this: it buffers the events until they are received regularly within a specified time period between the subsequent events. If there is a gap in the event flow (longer than the timespan) it should return propagate the events buffered so far. Having a look at how Buffer and Timeout is implemented, I could probably implement my BufferWithTimeout method (if everyone have one, please share with me), but I wonder if this can be achieved just by combining the existing methods. Any ideas?

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• Incongruity between Eclipse Outline/Package perspective and source code being displayed - Java error generated at runtime

  - by David Daedalus

  I've been debugging a Java application and have encountered something odd. When a particular method is called, Java throws a ClassNotFoundException. Unfortunately, the methods in question (the invoking and the 'missing' one) are inside a JAR file for which I have no documentation or source. To get at the source, I used JD-GUI (a Java JAR reverse engineer-er) and the JD plugin for Eclipse. As far as I can tell, the class in question exists inside the JAR file. This because JD-GUI displays it inside the JAR, and from within Eclipse I can see it listed along with the constructors and methods. My question is why the source being displayed in Eclipse is for a different class (that also exists)? This program was built with Ant - is it possible the problem lies there? Screenshot below for your viewing pleasure - and thanks in advance for your help!

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• Efficiency of while(true) ServerSocket Listen

  - by Submerged

  I am wondering if a typical while(true) ServerSocket listen loop takes an entire core to wait and accept a client connection (Even when implementing runnable and using Thread .start()) I am implementing a type of distributed computing cluster and each computer needs every core it has for computation. A Master node needs to communicate with these computers (invoking static methods that modify the algorithm's functioning). The reason I need to use sockets is due to the cross platform / cross language capabilities. In some cases, PHP will be invoking these java static methods. I used a java profiler (YourKit) and I can see my running ServerSocket listen thread and it never sleeps and it's always running. Is there a better approach to do what I want? Or, will the performance hit be negligible? Please, feel free to offer any suggestion if you can think of a better way (I've tried RMI, but it isn't supported cross-language. Thanks everyone

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• VS 2010 Class Diagram Error "The type cannot be edited..."

  - by Eric J.

  A few of the classes on a VS 2010 class diagram are displayed with a red title. The Class Details window shows all of the methods, properties, fields and correctly shows no events. However, there's an entry under each of methods, properties, fields and events that states where the name should be: "The type cannot be edited because the source code file contains an error." However, the source file builds with no errors or warnings. Anyone seen this? Any idea how to fix it?

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• MovieViewControl unable to become a receiver during Broadcast

  - by Paulina D

  Hi! I'm currently trying to catch a broadcast message with the MovieViewControl class, already added the filter in the Manifest //In MovieViewControl private static final String SERVICECMD = "com.android.music.musicservicecommand"; private static final String CMDNAME = "command"; private static final String CMDPAUSE = "pause"; @Override public void onReceive(Context context, Intent intent) { String intentAction = intent.getAction(); if (AudioManager.ACTION_AUDIO_BECOMING_NOISY.equals(intentAction)) { Intent i = new Intent(intent.ACTION_MAIN); i.setAction(SERVICECMD); i.putExtra(CMDNAME, CMDPAUSE); mVideoView.pause(); context.startActivity(i); } } but when I do my trial, I get this (very) huge exception: W/dalvikvm( 1630): threadid=3: thread exiting with uncaught exception (group=0x4001b1b8) E/AndroidRuntime( 1630): Uncaught handler: thread main exiting due to uncaught exception E/AndroidRuntime( 1630): java.lang.RuntimeException: Unable to instantiate receiver com.android.gallery.MovieViewControl: java.lang.ClassNotFoundException: com.android.gallery.MovieViewControl in loader dalvik.system.PathClassLoader@438ff048 E/AndroidRuntime( 1630): at android.app.ActivityThread.handleReceiver(ActivityThread.java:2616) E/AndroidRuntime( 1630): at android.app.ActivityThread.access$3100(ActivityThread.java:119) E/AndroidRuntime( 1630): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1913) E/AndroidRuntime( 1630): at android.os.Handler.dispatchMessage(Handler.java:99) E/AndroidRuntime( 1630): at android.os.Looper.loop(Looper.java:123) E/AndroidRuntime( 1630): at android.app.ActivityThread.main(ActivityThread.java:4363) E/AndroidRuntime( 1630): at java.lang.reflect.Method.invokeNative(Native Method) E/AndroidRuntime( 1630): at java.lang.reflect.Method.invoke(Method.java:521) E/AndroidRuntime( 1630): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860) E/AndroidRuntime( 1630): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618) E/AndroidRuntime( 1630): at dalvik.system.NativeStart.main(Native Method) E/AndroidRuntime( 1630): Caused by: java.lang.ClassNotFoundException: com.android.gallery.MovieViewControl in loader dalvik.system.PathClassLoader@438ff048 E/AndroidRuntime( 1630): at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:243) E/AndroidRuntime( 1630): at java.lang.ClassLoader.loadClass(ClassLoader.java:573) E/AndroidRuntime( 1630): at java.lang.ClassLoader.loadClass(ClassLoader.java:532) E/AndroidRuntime( 1630): at android.app.ActivityThread.handleReceiver(ActivityThread.java:2609) E/AndroidRuntime( 1630): ... 10 more Any hints on what might I be missing? Thanks in advance!

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• Do fluent interfaces significantly impact runtime performance of a .NET application?

  - by stakx

  I'm currently occupying myself with implementing a fluent interface for an existing technology, which would allow code similar to the following snippet: using (var directory = Open.Directory(@"path\to\some\directory")) { using (var file = Open.File("foobar.html").In(directory)) { // ... } } In order to implement such constructs, classes are needed that accumulate arguments and pass them on to other objects. For example, to implement the Open.File(...).In(...) construct, you would need two classes: // handles 'Open.XXX': public static class OpenPhrase { // handles 'Open.File(XXX)': public static OpenFilePhrase File(string filename) { return new OpenFilePhrase(filename); } // handles 'Open.Directory(XXX)': public static DirectoryObject Directory(string path) { // ... } } // handles 'Open.File(XXX).XXX': public class OpenFilePhrase { internal OpenFilePhrase(string filename) { _filename = filename } // handles 'Open.File(XXX).In(XXX): public FileObject In(DirectoryObject directory) { // ... } private readonly string _filename; } That is, the more constituent parts statements such as the initial examples have, the more objects need to be created for passing on arguments to subsequent objects in the chain until the actual statement can finally execute. Question: I am interested in some opinions: Does a fluent interface which is implemented using the above technique significantly impact the runtime performance of an application that uses it? With runtime performance, I refer to both speed and memory usage aspects. Bear in mind that a potentially large number of temporary, argument-saving objects would have to be created for only very brief timespans, which I assume may put a certain pressure on the garbage collector. If you think there is significant performance impact, do you know of a better way to implement fluent interfaces?

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• what is the idea behind scaling an image using lanczos?

  - by banister

  Hi, I'm interested in image scaling algorithms and have implemented the bilinear and bicubic methods. However, I have heard of the lanczos and other more sophisticated methods for even higher quality image scaling and I am very curious how they work. Could someone here explain the basic idea behind scaling an image using lanczos (both upscaling and downscaling) and why it results in higher quality? I do have a background in fourier analysis and have done some signal processing stuff in the past, but not with relation to image processing, so don't be afraid to use terms like "frequency response" and such in your answer :) EDIT: I guess what i really want to know is the concept and theory behind using a convolution filter for interpolation. (Note: i have already read the wikipedia article on lanczos resampling but it didn't have nearly enough detail for me) thanks alot!

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• Java dynamic proxy questions.

  - by Tony

  1.Does dynamic proxy instance subclass the target class? The java doc says the proxy instance implements "a list of interfaces", says nothing about subclassing, but through debugging, I saw that the proxy instance did inherit the target class properites.What does the "a list of interfaces " mean? Can I exclude those interfaces implemented by target class ? 2.Can I invoke target class specific methods on a proxy instance? 3. I think dynamic proxy is an interface methods invocation proxy but rather than a target class proxy, is that right (I am deeply infected by hibernate proxy object concept)?

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• Threads in Java

  - by owca

  I've created simple program to test Threads in Java. I'd like it to print me numbers infinitely, like 123123123123123. Dunno why, but currently it stops after one cycle finishing 213 only. Anyone knows why ? public class Main { int number; public Main(int number){ } public static void main(String[] args) { new Infinite(2).start(); new Infinite(1).start(); new Infinite(3).start(); } } class Infinite extends Thread { static int which=1; static int order=1; int id; int number; Object console = new Object(); public Infinite(int number){ id = which; which++; this.number = number; } @Override public void run(){ while(1==1){ synchronized(console){ if(order == id){ System.out.print(number); order++; if(order >= which){ order = 1; } try{ console.notifyAll(); console.wait(); } catch(Exception e) {} } else { try{ console.notifyAll(); console.wait(); } catch(Exception e) {} } } try{Thread.sleep(0);} catch(Exception e) {} } } }

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• Why aren't my coordinates matching my JFrame size?

  - by AsLanFromNarnia

  I want to do some drawing in a JPanel but the enclosing JFrame size doesn't seem to match where I've asked the coordinates to be drawn. In my example code, the JFrame size is set to (700, 700) and the last point is drawn at (600, 600). I would expect this point to be drawn 100 pixels away from the right and bottom edges but it isn't (please see screenshot). Here's the code I'm using: import java.awt.Graphics; import javax.swing.JFrame; import javax.swing.JPanel; public class Scratch extends JPanel { static int frameWidth = 700; static int frameHeight = 700; public static void main(String[] args) { JFrame frame = new JFrame(); frame.setSize(frameWidth, frameHeight); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); Scratch scratch = new Scratch(); frame.getContentPane().add(scratch); frame.setVisible(true); } @Override public void paintComponent(Graphics g) { g.drawRect(100, 100, 1, 1); g.drawString("100", 100, 100); g.drawRect(200, 200, 1, 1); g.drawString("200", 200, 200); g.drawRect(300, 300, 1, 1); g.drawString("300", 300, 300); g.drawRect(400, 400, 1, 1); g.drawString("400", 400, 400); g.drawRect(500, 500, 1, 1); g.drawString("500", 500, 500); g.drawRect(600, 600, 1, 1); g.drawString("600", 600, 600); } }

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• Looking for an explanation of the 'Asynchronous' word in .Net?

  - by IbrarMumtaz

  I need someone to explain the following names; Asynchronous Delegates. Asynchronous methods. Asynchronous events. I'm currently going over this for my 70-536 exam and I am covering all my bases so far. The threading chapter and online resources have been good to me on my second read through. Still though, the names used above mean absolutely nothing to me? I would really appreciate the meaning behind the word 'Asynchronous' and its relevance to Delegates, methods and events. Feel free to go into as much detail as you like. Thanks, Ibrar

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• Keep Hibernate Initializer from Crashing Program

  - by manyxcxi

  I have a Java program using a basic Hibernate session factory. I had an issue with a hibernate hbm.xml mapping file and it crashed my program even though I had the getSessionFactory() call in a try catch try { session = SessionFactoryUtil.getSessionFactory().openStatelessSession(); session.beginTransaction(); rh = getRunHistoryEntry(session); if(rh == null) { throw new Exception("No run history information found in the database for run id " + runId_ + "!"); } } catch(Exception ex) { logger.error("Error initializing hibernate"); } It still manages to break out of this try/catch and crash the main thread. How do I keep it from doing this? The main issue is I have a bunch of cleanup commands that NEED to be run before the main thread shuts down and need to be able to guarantee that even after a failure it still cleans up and goes down somewhat gracefully. The session factory looks like this: public class SessionFactoryUtil { private static final SessionFactory sessionFactory; static { try { // Create the SessionFactory from hibernate.cfg.xml sessionFactory = new Configuration().configure().buildSessionFactory(); } catch (Throwable ex) { // Make sure you log the exception, as it might be swallowed System.err.println("Initial SessionFactory creation failed." + ex); throw new ExceptionInInitializerError(ex); } } public static SessionFactory getSessionFactory() { try { return sessionFactory; } catch(Exception ex) { return null; } } }

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• Simulating a button press without performClick: (cocoa osx/cocotron)

  - by Michael Minerva

  I need to be able to display popup menu when I press an openGL object. I was able to accomplish this by triggering the performClick: of an inviible NSPopupButton and also by triggering the performClickWithFrame:inView: of an NSPopupButtonCell. Both of these methods were successful on OSX but I also need to target the PC and unfortunately performClickWithFrame:inView: is unimplemented in cocotron and performClick does not cause the menu to be displayed when executed on an NSPopupButton (on cocotron). Now there must be someway for this to work because the NSPopupButton does sucesfully display the NSPopupButtonCell when it is clicked but I know it does not accomplish by calling performClick:. Can I access these lower levels methods used by the NSPopupButton to display my menu or force the invisible NSPopupButton to display its menu? If so can anyone link me to some info about this?

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• NSThread running a class

  - by Thomas Joulin

  Hi, Every the example I find on the internet (including Apple doc) sets the target to self like this : [NSThread detachNewThreadSelector:@selector(threadedTask) toTarget:self withObject:nil]; Since i would like to do a more complex task in background (involving multiple methods), I thought of creating a class Task called like this : Task *task = [[Task alloc] init]; [NSThread detachNewThreadSelector:@selector(main) toTarget:task withObject:nil]; but I wonder, how will be handled the instance variables of my class Task ? in my method main can I safely call methods of my class Task using [self myMethod] and modifying members variables assuming I'm the only thread accessing it ? This way of handling threads seems weird to me, sorry if my question is stupid ^^ Thanks in advance

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• How much does Website Development cost nowadays?

  - by Andreas Grech

  I am thinking of setting up my own freelance business but coming from a workplace that offers a particular service to huge clients, I do not know what are the current charges for websites are nowadays. I know that as technology just keeps changing and changing (most of the time, for the better...), the amount you charge for a single website is constantly differing. Like for example, I don't think static websites (with just static html pages) are that expensive today, no? (as i said, I might be mistaken since I haven't really touched on this freelance industry yet) So, freelance web-developers out there, can you give me estimates on how much you charge for your clients? Some examples of websites that I want to know an approx charge: ~10 static html pages ~10 dhtml pages (with maybe a flasy menu on the top/side) Database driven websites with a standard CMS (be it the one you developed, or an existing one) Database driven but with a custom-built cms for the particular client Using an existing template for a design Starting the design from scratch etc... I know that the normally clients don't really care about the technologies used to construct their websites, but do you charge differently according to which technology you use to build the website with?; as in, is the technology a factor when setting the price? ...being ASP.Net, PHP, Ruby On Rails etc... Also, how do you go on about charging your clients for your services? What are the major factors that you consider when setting a price tag for a website to a client ? And better yet, how do you even find prospective clients? <= [or should I leave this question for a different post?] Btw, in your post, also mention some numbers (in cash values, be it in USD, GBP, EUR or anything) because I want to be able to take calculate some averages from this post when some answers stack up

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• Is there a good reflection library available for Scala?

  - by Erik Engbrecht

  I'm working on a library that needs reflection, and needs Scala-specific information as opposed to what is available via the standard Java reflection API. Right now I'm using the undocumented code in scalap (the Scala equivalent to javap) and trying to associate the data it provides with Java reflection objects so that I can call methods and such (scalap just parses class files). I found this but there's nothing there... https://github.com/dubochet/scala-reflection ...and I've searched the Scala SVN repo for traces of it and failed to find it there, either (but it could be I just missed it). Does anyone know of a Scala reflection library that provides information similar to what scalap provides but also allows you to call methods, access fields, etc like the Java reflection library?

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• to connect matlab with java

  - by user304005

  Through the below given code I was able to connect to matlab. But I was not able to execute the script file containing matlab code...Please help me to modify the code so as to execute the matlab code.... Here luck2 is a .m file.... import java.io.InputStreamReader; import java.io.*; public class matlab { private static File myMATLABScript; public static String runScript(File luck2) { String output = "" ; String error = ""; try { String commandToRun ="C:\\Program Files\\MATLAB\\R2009a\\bin\\matlab -nodisplay <" + "Z:\\sem\\java\\luck2"; //String commandToRun = "matlab -nosplash -r myMATLABScript -nodisplay -nodesktop < " + opentxt; System.out.println(commandToRun); Process p = Runtime.getRuntime().exec(commandToRun); String s; BufferedReader stdInput = new BufferedReader(new InputStreamReader(p.getInputStream())); BufferedReader stdError = new BufferedReader(new InputStreamReader(p.getErrorStream())); System.out.println("\nHere is the standard output of the command:\n"); while ((s = stdInput.readLine()) != null) { System.out.println("haiiiiiiiiiiii"); output = s + "\n"; System.out.println(s); } while ((s = stdError.readLine()) != null) { error = s + "\n"; System.out.println(s); } } catch (Exception e) { System.out.println("exception happened here what I know:"); e.printStackTrace(); System.exit(-1); } return output + error; } public static void main(String[] args) throws IOException { matlab m = new matlab(); matlab.runScript(myMATLABScript); //matlab.runScript(); } }

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• Iphone -- init method of an abstract class

  - by William Jockusch

  I want to create classes Car, Vehicle, and Airplane with the following properties: Car and Airplane are both subclasses of Vehicle. Car and Airplane both have an initWithString method. The acceptable input strings for Car's and Airplane's initWithString methods do not overlap. Vehicle is "almost abstract", in the sense that any initialized instance should be either a Car or an Airplane. It is possible to pass a string into Vehicle and get back an instance of Car, an instance of Airplane, or nil, depending on the input string. Any particular design pattern I should prefer? In particular for Vehicle's initWithString and/or newVehicleWithString methods.

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• C# app running as either Windows Form or as Console Application

  - by Aeolien

  I am looking to have one of my Windows Forms applications be run programmatically—from the command line. In preparation, I have separated the logic in its own class from the Form. Now I am stuck trying to get the application to switch back and forth based on the presence of command line arguments. Here is the code for the main class: static class Program { /// <summary> /// The main entry point for the application. /// </summary> [STAThread] static void Main() { string[] args = Environment.GetCommandLineArgs(); if (args.Length > 1) // gets passed its path, by default { CommandLineWork(args); return; } Application.EnableVisualStyles(); Application.SetCompatibleTextRenderingDefault(false); Application.Run(new Form1()); } private static void CommandLineWork(string[] args) { Console.WriteLine("It works!"); Console.ReadLine(); } where Form1 is my form and the It works! string is just a placeholder for the actual logic. Right now, when running this from within Visual Studio (with command line arguments), the phrase It works! is printed to the Output. However, when running the /bin/Debug/Program.exe file (or /Release for that matter) the application crashes. Am I going about this the right way? Would it make more sense (i.e. take less developer time) to have my logic class be a DLL that gets loaded by two separate applications? Or is there something entirely different that I'm not aware of? Thanks in advance!

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• Fixing javascript Array functions in Internet Explorer (indexOf, forEach, etc)

  - by Chas Emerick

  As detailed elsewhere, and otherwise apparently well-known, Internet Explorer (definitely 7, and in some instances, 8) do not implement key functions, in particular on Array (such as forEach, indexOf, etc). There are a number of workarounds here and there, but I'd like to fold a proper, canonical set of implementations into our site rather than copy and paste or hack away at our own implementations. I've found js-methods, which looks promising, but thought I'd post here to see whether another library comes more highly-recommended. A couple of misc. criteria: the lib should just be a no-op for those functions that a browser already has implementations for (js-methods appears to do quite well here) non-GPL, please, though LGPL is acceptable

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• Scheme: what are the benefits of letrec?

  - by Ixmatus

  While reading "The Seasoned Schemer" I've begun to learn about letrec. I understand what it does (can be duplicated with a Y-Combinator) but the book is using it in lieu of recurring on the already defined function operating on arguments that remain static. An example of an old function using the defined function recurring on itself (nothing special): (define (substitute new old lat) (cond ((null? l) '()) ((eq? (car l) old) (cons new (substitute new old (cdr l)))) (else (cons (car l) (substitute new old (cdr l)))))) Now for an example of that same function but using letrec: (define (substitute new old lat) (letrec ((replace (lambda (l) (cond ((null? l) '()) ((eq? (car l) old) (cons new (replace (cdr l)))) (else (cons (car l) (replace (cdr l)))))))) (replace lat))) Aside from being slightly longer and more difficult to read I don't know why they are rewriting functions in the book to use letrec. Is there a speed enhancement when recurring over a static variable this way because you don't keep passing it?? Is this standard practice for functions with arguments that remain static but one argument that is reduced (such as recurring down the elements of a list)? Some input from more experienced Schemers/LISPers would help!

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