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• What does WIX's CloseApplication functionality do and how would can the application respond to such

  - by tronda

  In the WIX setup I've got, when upgrading the application I have set a requirement to close down applications which might hold on to files which needs to be updated: <util:CloseApplication Id="CloseMyApp" Target="[MyAppExe]" CloseMessage="no" Description="!(loc.MyAppStillRunning)" RebootPrompt="no" ElevatedCloseMessage="no" /> The application on the other hand will capture closing down the window with a "user friendly" dialog box where the user can confirm that he or she wants to close down the application. I've experienced problems with the CloseApplication, and one theory is that the dialog box stops the application from closing. So the question is: Could this be a possible problem? If so - how can I have this confirmation dialog box and still behave properly when the installer asks the application to close down? Must I listen to Win32 messages (such as WM_QUIT/WM_CLOSE) or is there a .NET API which I can use to respond properly to these events?

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• Why won't this Apache modrewrite RewriteRule work?

  - by Jason Rhodes

  I'm trying to get Apache mod rewrite to work on my local machine. I'm running OSX with PHP 5 and the Apache mod rewrite module is enabled. I have a directory called localhost/~Jason/hfh/admin with various PHP includes called based on a $_GET variable. I want to let users type (in theory) localhost/~Jason/hfh/admin/pages and have that URL stay in the address bar, while what gets displayed is localhost/~Jason/hfh/admin/?admin=pages So. I've created a .htaccess file that sits in the /hfh directory. Inside, I've put this mod rewrite text: RewriteEngine On RewriteRule ^admin/([^/.]+)/?$ admin/?admin=$1 [L] When I go to the browser and type localhost/~Jason/hfh/admin/pages I get a "Problem loading page" error, and Firefox says, "Oops. Firefox can't load this page for some reason." Can anyone help me figure this out? I have such a hard time with regex and mod rewrite...

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• How to compile x64 asp.net website?

  - by Eran Betzalel

  I'm trying to compile (using Visual Studio) an ASP.Net website with the Chilkat library. The compilation fails due to this error: Could not load file or assembly 'ChilkatDotNet2, Version=9.0.8.0, Culture=neutral, PublicKeyToken=eb5fc1fc52ef09bd' or one of its dependencies. An attempt was made to load a program with an incorrect format. I've been told that this error occurs because of platform noncompliance. The weird thing is that although the compilation fails, the site works once accessed from a browser. My theory is that the IIS compilation uses csc.exe compiler from the Framework64 (64 bit) folder while the Visual Studio uses csc.exe compiler from the Framework (32 bit) folder. If this is acually it, how can I configure my Visual studio to run with the 64 bit compiler for ASP.Net sites? This is my current development configuration: Windows 7 (x64). Visual Studio 2008 Pro (x86 of course...). Chilkat library (x64) IIS/Asp.net (x64).

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• Replacing build.xml with Build.java - using Java and the Ant libraries as a build system

  - by Dean Schulze

  I've grown disillusioned with Groovy based alternatives to Ant. AntBuilder doesn't work from within Eclipse, the Groovy plugin for Eclipse is disappointing, and Gradle just isn't ready yet. The Ant documentation has a section titled "Using Ant Tasks Outside of Ant" which gives a teaser for how to use the Ant libraries from Java code. There's another example here: http://www.mail-archive.com/[email protected]/msg16310.html In theory it seems simple enough to replace build.xml with Build.java. The Ant documentation hints at some undocumented dependencies that I'll have to discover (undocumented from the point of view of using Ant from within Java). Given the level of disappointment with Ant scripting, I wonder why this hasn't been done before. Perhaps it has and isn't a good build system. Has anyone tried writing build files in Java using the Ant libraries?

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• CSS layout with 2 columns, taking up all width of browser, where left column can collapse

  - by Matt Dawdy

  I want to have a 2 column layout, and have the left column able to be 200 px at first, and have a "shrink" button to shrink it down to 10px, and have the right column expand to fill all the rest of the available space. Then if they click on the "show" button (which will be all they see in the now 10px wide left column) have the left grow back to 200px and have the right column shrink by that amount. I can't figure out how to make the right column grown and shrink without knowing the exact width of the window. I hope this makes sense, and I really hope someone can point me in the right direction. Browser requirements are IE8, FF3.6, Safari, and Chrome, so in theory I can use some advanced CSS techniques. At least I don't have to support IE6.

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• How to retrieve row count of one-to-many relation while also including original entity?

  - by kaa

  Say I have two entities Foo and Bar where Foo has-many Bar's, class Foo { int ImportantNumber { get; set; } IEnumerable<Bar> Bars { get; set; } } class FooDTO { Foo Foo { get; set; } int BarCount { get; set; } } How can I efficiently sum up the number of Bars per Foo in a DTO using a single query, preferrably only with the Criteria interface. I have tried any number of ways to get the original entity out of a query with ´SetProjection´ but no luck. The current theory is to do something like SELECT Foo.*, BarCounts.counts FROM Foo LEFT JOIN ( SELECT fooId, COUNT(*) as counts FROM Bar GROUP BY fooId ) AS BarCounts ON Foo.id=BarCounts.fooId but with Criterias, and I just can't seem to figure out how.

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• Object Oriented database development jobs

  - by GigaPr

  Hi, i am a software engineering student currently looking for a job as developer. I have been offered a position in a company which implements software using object oriented databases. these are something completely new for me as at university we never worked on it, just some theory. my questions are do you think is a good way to start my career as developer? what is the job market for this type of developemnt? are these skills requested? what markets this technology touches? thanks

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• Making the domain-model of tic tac toe

  - by devoured elysium

  I am trying to make the domain model of a Tic Tac Toe game. I'll try then to go on through the various steps of the Unified Process and later implement it in some language (C# or Java). I'd like to have some feedback if I'm going on the right path: I've defined the game with two actors, Player O and Player X. I'm not sure about defining both a Tile and a Tile State. Maybe I should only define a Tile and have the 3 possible states specialize from it? I'm not sure what is best: to have both Player O and Player X be associations with Tic Tac Toe or have them inherit from Player that is associated with Tic Tac Toe. Following the design shown on the pic, in theory we could have a Tic Tac Toe concept with 2 Player O's, which wouldn't be correct. What is your opinion on this? Also, am I missing something in the diagram? Although I can't see any other actors for Tic Tac Toe, should I have any other? Thanks

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• MVC with cocoa/objective-c

  - by Leonardo

  Hi all, I have a strong j2ee background, and I am trying to move to objective-c for some desktop/iphone programming. I used many java web frameworks with mvc in mind, spring and struts ecc... so I am used to have servlet or controller which pass attributes to jsp pages, which is the view. In jsp pages with jstl you can call this attribute and render to video. In this way controller and view are (in theory) clearly separated. With xcode, I can easily recognize the controller and the view built with IBuilder. All the tutorial I found, shown the controller which go and change directly labels or text fields. So my two questions: seems to me that there's no separation between the two (controller and view), where I am wrong in that ? is there a way for a controller to pack all objects in a kind of context in a j2ee way and have the view read that context ? thanks Leonardo

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• Is it easier to write a recursive-descent parser using an EBNF or a BNF?

  - by Vivin Paliath

  I've got a BNF and EBNF for a grammar. The BNF is obviously more verbose. I have a fairly good idea as far as using the BNF to build a recursive-descent parser; there are many resources for this. I am having trouble finding resources to convert an EBNF to a recursive-descent parser. Is this because it's more difficult? I recall from my CS theory classes that we went over EBNFs, but we didn't go over converting them into a recursive-descent parser. We did go over converting BNF's into a recursive-descent parser. The reason I'm asking is because the EBNF is more compact. From looking at the EBNF's in general, I notice that terms enclosed between { and } can be converted into a while loop. Are there any other guidelines or rules?

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• Can't find controls in FormView.InsertItemTemplate even on DataBound event

  - by abatishchev

  I have FormView in my page markup: <asp:FormView ruanat="server" ID="FormView1" OnDataBound="FormView1_DataBound" DataSourceID="SqlDataSource1"> <InsertItemTemplate> <uc:UserControl1 runat="server" ID="ucUserControl1" /> </InsertItemTemplate> </asp:FormView> <asp:SqlDataSource runat="server" ID="SqlDataSource1" SelectCommand="EXEC someSP" /> It's code-behind: protected void FormView1_DataBound (object sender, EventArgs e) { var c1 = ((FormView)sender).FindControl("ucUserControl1"); // returns null var c2 = FormView1.FindControl("ucUserControl1"); // also returns null } In theory, I'm able to find control on FormView after it being data bound. But I'm not. Why?

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• Which programming languages aren't considered high-level?

  - by hilo

  In informatics theory I hear and read about high-level and low-level languages all time. Yet I don't understand why this is still relevant as there aren't any (relevant) low-level languages except assembler in use today. So you get: Low-level Assembler Definitely not low-level C BASIC FORTRAN COBOL ... High-level C++ Ruby Python PHP ... And if assembler is low-level, how could you put for example C into the same list. I mean: C is extremely high-level compared to assembler. Same even for COBOL, Fortran, etc. So why does everybody keep mentioning high and low-level languages if assembler is really the only low-level language.

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• Studying MySQL, SQLite source code to learn about RDBMS implementation

  - by Yang

  I know implementing database is a huge topic, but I want to have a basic understanding of how database systems work (e.g. memory management, binary tree, transaction, sql parsing, multi-threading, partitions, etc) by investigating the source code of the database. Since there are a few already proven very robust open source databases like mysql, sqlite and so on. However, the code are very complicated and I have no clue where to start. Also I find that the old school database textbooks are only explaining the theory, not the implementation details. Can anyone suggest how I should get started and if there are any books that emphasis on the technology and techniques of building dbms used in modern database industry?

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• Covariance and Contravariance on the same type argument

  - by William Edmondson

  The C# spec states that an argument type cannot be both covariant and contravariant at the same time. This is apparent when creating a covariant or contravariant interface you decorate your type parameters with "out" or "in" respectively. There is not option that allows both at the same time ("outin"). Is this limitation simply a language specific constraint or are there deeper, more fundamental reasons based in category theory that would make you not want your type to be both covariant and contravariant? Edit: My understanding was that arrays were actually both covariant and contravariant. public class Pet{} public class Cat : Pet{} public class Siamese : Cat{} Cat[] cats = new Cat[10]; Pet[] pets = new Pet[10]; Siamese[] siameseCats = new Siamese[10]; //Cat array is covariant pets = cats; //Cat array is also contravariant since it accepts conversions from wider types cats = siameseCats;

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• OpenGL Game development for the Desktop / Platform issues

  - by anon

  Does anyone have experience writing professional OpenGL games on Windows? For the Mac, due to apple's control, the OS seems quite "uniform". For windows, due to different hardware, different drivers installed, etc ... the hardware base seems to have many many different configurations. In theory, OpenGL provides a API that abstracts all this away. In practice, many drivers are often buggy and have weird cases -- has this been a problem for developing games on Windows? Thanks!

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• Building an XML editor in java and RichFaces

  - by Mark Lewis

  Hello I'm building an XML editor using the above technologies. In essence, I want to read in a whole XML file to a java object, and refer using this object to each element in the XML node tree (grouped into entries) to display the content locked, have separate padlocks for the user to click to 'unlock' an entry allow overwriting of the data, and to submit this entry. 'Add entry', 'Duplicate entry', 'Delete entry' are also functions I'd like to add. I already use dom4j and XPath to access areas of the XML file so some of the work in theory is already done. Given the above, I was going to use these two together with inplaceInputs to allow the user to edit the XML and JSF validators to check the data coming in. Is this the best way to approach this problem, or is there a more straightforward route than XPathing a whole record? I started looking at jaxb but I'm new at java and jsf but I've got the feeling I won't be by the end.. Thanks

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• What is the right tool to detect VMT or heap corruption in Delphi ?

  - by Roland Bengtsson

  I'm a member in a team that use Delphi 2007 for a larger application and we suspect heap corruption because sometimes there are strange bugs that have no other explanation. I believe that the Rangechecking option for the compiler is only for arrays. I want a tool that give an exception or log when there is a write on a memory address that is not allocated by the application. Regards EDIT: The error is of type: Error: Access violation at address 00404E78 in module 'BoatLogisticsAMCAttracsServer.exe'. Read of address FFFFFFDD EDIT2: Thanks for all suggestions. Unfortunately I think that the solution is deeper than that. We use a patched version of Bold for Delphi as we own the source. Probably there are some errors introduced in the Bold framwork. Yes we have a log with callstacks that are handled by JCL and also trace messages. So a callstack with the exception can lock like this: 20091210 16:02:29 (2356) [EXCEPTION] Raised EBold: Failed to derive ServerSession.mayDropSession: Boolean OCL expression: not active and not idle and timeout and (ApplicationKernel.allinstances->first.CurrentSession <> self) Error: Access violation at address 00404E78 in module 'BoatLogisticsAMCAttracsServer.exe'. Read of address FFFFFFDD. At Location BoldSystem.TBoldMember.CalculateDerivedMemberWithExpression (BoldSystem.pas:4016) Inner Exception Raised EBold: Failed to derive ServerSession.mayDropSession: Boolean OCL expression: not active and not idle and timeout and (ApplicationKernel.allinstances->first.CurrentSession <> self) Error: Access violation at address 00404E78 in module 'BoatLogisticsAMCAttracsServer.exe'. Read of address FFFFFFDD. At Location BoldSystem.TBoldMember.CalculateDerivedMemberWithExpression (BoldSystem.pas:4016) Inner Exception Call Stack: [00] System.TObject.InheritsFrom (sys\system.pas:9237) Call Stack: [00] BoldSystem.TBoldMember.CalculateDerivedMemberWithExpression (BoldSystem.pas:4016) [01] BoldSystem.TBoldMember.DeriveMember (BoldSystem.pas:3846) [02] BoldSystem.TBoldMemberDeriver.DoDeriveAndSubscribe (BoldSystem.pas:7491) [03] BoldDeriver.TBoldAbstractDeriver.DeriveAndSubscribe (BoldDeriver.pas:180) [04] BoldDeriver.TBoldAbstractDeriver.SetDeriverState (BoldDeriver.pas:262) [05] BoldDeriver.TBoldAbstractDeriver.Derive (BoldDeriver.pas:117) [06] BoldDeriver.TBoldAbstractDeriver.EnsureCurrent (BoldDeriver.pas:196) [07] BoldSystem.TBoldMember.EnsureContentsCurrent (BoldSystem.pas:4245) [08] BoldSystem.TBoldAttribute.EnsureNotNull (BoldSystem.pas:4813) [09] BoldAttributes.TBABoolean.GetAsBoolean (BoldAttributes.pas:3069) [10] BusinessClasses.TLogonSession._GetMayDropSession (code\BusinessClasses.pas:31854) [11] DMAttracsTimers.TAttracsTimerDataModule.RemoveDanglingLogonSessions (code\DMAttracsTimers.pas:237) [12] DMAttracsTimers.TAttracsTimerDataModule.UpdateServerTimeOnTimerTrig (code\DMAttracsTimers.pas:482) [13] DMAttracsTimers.TAttracsTimerDataModule.TimerKernelWork (code\DMAttracsTimers.pas:551) [14] DMAttracsTimers.TAttracsTimerDataModule.AttracsTimerTimer (code\DMAttracsTimers.pas:600) [15] ExtCtrls.TTimer.Timer (ExtCtrls.pas:2281) [16] Classes.StdWndProc (common\Classes.pas:11583) The inner exception part is the callstack at the moment an exception is reraised. EDIT3: The theory right now is that the Virtual Memory Table (VMT) is somehow broken. When this happen there is no indication of it. Only when a method is called an exception is raised (ALWAYS on address FFFFFFDD, -35 decimal) but then it is too late. You don't know the real cause for the error. Any hint of how to catch a bug like this is really appreciated!!! We have tried with SafeMM, but the problem is that the memory consumption is too high even when the 3 GB flag is used. So now I try to give a bounty to the SO community :) EDIT4: One hint is that according the log there is often (or even always) another exception before this. It can be for example optimistic locking in the database. We have tried to raise exceptions by force but in test environment it just works fine. EDIT5: Story continues... I did a search on the logs for the last 30 days now. The result: "Read of address FFFFFFDB" 0 "Read of address FFFFFFDC" 24 "Read of address FFFFFFDD" 270 "Read of address FFFFFFDE" 22 "Read of address FFFFFFDF" 7 "Read of address FFFFFFE0" 20 "Read of address FFFFFFE1" 0 So the current theory is that an enum (there is a lots in Bold) overwrite a pointer. I got 5 hits with different address above. It could mean that the enum holds 5 values where the second one is most used. If there is an exception a rollback should occur for the database and Boldobjects should be destroyed. Maybe there is a chance that not everything is destroyed and a enum still can write to an address location. If this is true maybe it is possible to search the code by a regexpr for an enum with 5 values ? EDIT6: To summarize, no there is no solution to the problem yet. I realize that I may mislead you a bit with the callstack. Yes there are a timer in that but there are other callstacks without a timer. Sorry for that. But there are 2 common factors. An exception with Read of address FFFFFFxx. Top of callstack is System.TObject.InheritsFrom (sys\system.pas:9237) This convince me that VilleK best describe the problem. I'm also convinced that the problem is somewhere in the Bold framework. But the BIG question is, how can problems like this be solved ? It is not enough to have an Assert like VilleK suggest as the damage has already happened and the callstack is gone at that moment. So to describe my view of what may cause the error: Somewhere a pointer is assigned a bad value 1, but it can be also 0, 2, 3 etc. An object is assigned to that pointer. There is method call in the objects baseclass. This cause method TObject.InheritsForm to be called and an exception appear on address FFFFFFDD. Those 3 events can be together in the code but they may also be used much later. I think this is true for the last method call. EDIT7: We work closely with the the author of Bold Jan Norden and he recently found a bug in the OCL-evaluator in Bold framework. When this was fixed these kinds of exceptions decreased a lot but they still occasionally come. But it is a big relief that this is almost solved.

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• How to stop OpenGL from applying blending to certain content? (cocos2d/iPhone/OpenGL)

  - by RexOnRoids

  Supporting Info: I use cocos2d to draw a sprite (graph background) on the screen (z:-1). I then use cocos2d to draw lines/points (z:0) on top of the background -- and make some calls to OpenGL blending functions before the drawing to SMOOTH out the lines. Problem: The problem is that: aside from producing smooth lines/points, calling these OpenGL blending functions seems to degrade the underlying sprite (graph background). So there is a tradeoff: I can either have (Case 1) a nice background and choppy lines/points, or I can have (Case 2) nice smooth lines/points and a degraded background. But obviously I need both. The Code: I have included code of the draw() method of the CCLayer for both cases explained above. As you can see, the code producing the difference between Case 1 and Case 2 seems to be 1 or 2 lines involving OpenGL Blending. Case 1 -- MainScene.h (CCLayer): -(void)draw{ int lastPointX = 0; int lastPointY = 0; GLfloat colorMAX = 255.0f; GLfloat valR; GLfloat valG; GLfloat valB; if([self.myGraphManager ready]){ valR = (255.0f/colorMAX)*1.0f; valG = (255.0f/colorMAX)*1.0f; valB = (255.0f/colorMAX)*1.0f; NSEnumerator *enumerator = [[self.myGraphManager.currentCanvas graphPoints] objectEnumerator]; GraphPoint* object; while ((object = [enumerator nextObject])) { if(object.filled){ /*Commenting out the following two lines induces a problem of making it impossible to have smooth lines/points, but has merit in that it does not degrade the background sprite.*/ //glEnable (GL_BLEND); //glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); glHint (GL_LINE_SMOOTH_HINT, GL_DONT_CARE); glEnable (GL_LINE_SMOOTH); glLineWidth(1.5f); glColor4f(valR, valG, valB, 1.0); ccDrawLine(ccp(lastPointX, lastPointY), ccp(object.position.x, object.position.y)); lastPointX = object.position.x; lastPointY = object.position.y; glPointSize(3.0f); glEnable(GL_POINT_SMOOTH); glHint(GL_POINT_SMOOTH_HINT, GL_NICEST); ccDrawPoint(ccp(lastPointX, lastPointY)); } } } } Case 2 -- MainScene.h (CCLayer): -(void)draw{ int lastPointX = 0; int lastPointY = 0; GLfloat colorMAX = 255.0f; GLfloat valR; GLfloat valG; GLfloat valB; if([self.myGraphManager ready]){ valR = (255.0f/colorMAX)*1.0f; valG = (255.0f/colorMAX)*1.0f; valB = (255.0f/colorMAX)*1.0f; NSEnumerator *enumerator = [[self.myGraphManager.currentCanvas graphPoints] objectEnumerator]; GraphPoint* object; while ((object = [enumerator nextObject])) { if(object.filled){ /*Enabling the following two lines gives nice smooth lines/points, but has a problem in that it degrades the background sprite.*/ glEnable (GL_BLEND); glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); glHint (GL_LINE_SMOOTH_HINT, GL_DONT_CARE); glEnable (GL_LINE_SMOOTH); glLineWidth(1.5f); glColor4f(valR, valG, valB, 1.0); ccDrawLine(ccp(lastPointX, lastPointY), ccp(object.position.x, object.position.y)); lastPointX = object.position.x; lastPointY = object.position.y; glPointSize(3.0f); glEnable(GL_POINT_SMOOTH); glHint(GL_POINT_SMOOTH_HINT, GL_NICEST); ccDrawPoint(ccp(lastPointX, lastPointY)); } } } }

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• Algorithm and data structure learning resources for dynamic programming

  - by Pranav

  Im learning dynamic programming now, and while I know the theory well, designing DP algorithms for new problems is still difficult. This is what i would really like now- A book or a website, which poses a problem which can be solved by dynamic programming. Also there is the solution with an explanation available, which i would like to see if i cant solve the problem even after butting my head at it for a few hours. Is there some resource that provides this sort of a thing for several categories of algorithms- like graph algorithms, dynamic programming, etc? P.S. I considered Topcoder, but the solutions there are not really appropriate for learning to implement efficient solutions.

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• Implementing PageRank using MapReduce

  - by Nick D.

  Hello, I'm trying to get my head around an issue with the theory of implementing the PageRank with MapReduce. I have the following simple scenario with three nodes: A B C. The adjacency matrix is here: A { B, C } B { A } The PageRank for B for example is equal to: (1-d)/N + d ( PR(A) / C(A) ) N = number of incoming links to B PR(A) = PageRank of incoming link A C(A) = number of outgoing links from page A I am fine with all the schematics and how the mapper and reducer would work but I cannot get my head around how at the time of calculation by the reducer, C(A) would be known. How will the reducer, when calculating the PageRank of B by aggregating the incoming links to B will know the number of outgoing links from each page. Does this require a lookup in some external data source?

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• Difference between implementing an interface and applying an attribute in C#

  - by RemotecUk

  This might be a stupid question but Ill ask anyway, I was reading "OOP Demystified: A Self-Teaching Guide by Jim Keogh and Mario Giannini" chapter 11 which covers interfaces. The examples in this book are C++. I noticed that C++ uses ISerializable to make a class serializable which you would implement where as in C# you just attribute the class with the [Serializable] attribute. What is the key difference here? Is it that with an interface you must provide the implementation where as if you attribute something the compiler will work out the implementation for you? I guess that with the [Serializable] attribute the .Net framework uses reflection to make the serialized object from the actual object. That said is it possible in that case to have an [Disposable] attribute or using my theory above the framework wont know how to actually dispose of an object hence you have to do it yourself? Would be grateful for a clarification. Thanks.

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• Looking for evolutionary music example code

  - by Dan Dyer

  I would like to implement an interactive evolutionary algorithm for generating music (probably just simple melodies to start with). I'd like to use JFugue for this. Its website claims that it is well-suited to evolutionary music, but I can't find any evolutionary examples. I already have a framework to provide the evolutonary machinery. What I am looking for is some simple, working code that demonstrates viable approaches for the musical part (e.g. suitable encodings and evolutionary operators for the evolved tunes). I have some ideas how it might be achieved, but I'm not particularly knowledgeable about music theory, so to start with I'd like to just reimplement something that is known to work. So does anybody have, or know of, any freely available code (any language is fine) that demonstrates one or more approaches to evolutionary music? EDIT: I'm specifically looking for evolutionary code rather than other techniques that could be used for music synthesis.

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• iphone - testing if an object exists

  - by Mike

  I have several apps in my app that can become nil at some point and I have methods that in theory are used to put these objects to nil. But, if I try to put to nil an object that does not exist, the app will crash. for example... [object1 release]; object1 = nil; //... and after that [object removeFromSuperview]; // this will crash Then I thought, why not testing to see if the object exists before removing... if (object1 != nil) [object removeFromSuperview]; // this will crash too, because object1 cannot be tested for nil because it does not exist How can I check if the object exists before testing if it is nil? something as if (object exists( { if(object != nil)) [object removeFromSuperview) } is this possible?

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• Suggestions for Single-Page Web Application Design?

  - by DaveDev

  My view is that unless you need to change the basic structure of the user interface, you should not have to reload the page at all for any user interactions. I'd like to approach my next ASP.NET MVC project with this in mind. Can anyone suggest any principles, patterns or practices* I should consider? Excellent book, btw. Still trying to wrap my head around some of the concepts though. I thought a question like this would help link the theory to a practical design. Thanks

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• Statistical approach to chess?

  - by Chinmay Kanchi

  Reading about how Google solves the translation problem got me thinking. Would it be possible to build a strong chess engine by analysing several million games and determining the best possible move based largely (completely?) on statistics? There are several such chess databases (this is one that has 4.5 million games), and one could potentially weight moves in identical (or mirrored or reflected) positions using factors such as the ratings of the players involved, how old the game is (to factor in improvements in chess theory) etc. Any reasons why this wouldn't be a feasible approach to building a chess engine?

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