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• Can aptitude for learning Programming paradigms be influenced by culture or native language's gramma

  - by DVK

  It is well known that different people have different aptitudes regarding various programming paradigms (e.g. some people have trouble learning non-procedural, especially functional languages. Some people have trouble understanding pointers - see Joel Spolsky's blog for musings on that. Some people have trouble grasping recursion). I was recently reading about a study that looked at how the grammar of someone's native language affected their speed of learning math. Can't find that article now but a quick googling found this reference. That led me to wondering whether someone's native culture or first language might affect their aptitude towards various programming paradigms. I'm more curious about positive influences - e.g. some trait that make it easier/faster for someone to learn a particular paradigm, for example native language grammar being very recursion-oriented. To be clear, I'm looking for how culture/language grammare may affect the difference between aptitude of the same person towards various paradigms as opposed to how it affects overall aptitude towards programming between different persons. Important: the only answers I'm interested in are either references to scientific studies, or personal observations from someone intimately familiar with a particular culture/language, including from their own experience. E.g. I'm not interested in your opinion of how Chinese being your first language affects anything unless you speak Chinese or worked with extremely large set of Chinese-native programmers extensively. I'm OK with your guesstimates not based on scientific studies, but please be sure to supply your reasoning about plausible causes of your observation. I'm not interested in culture-bashing (any such commends will be deleted or flagged for deletion). I'm also not particularly interested in culture-building - we all know Linus is from Finland and Tetris was written in Russia and Larry Wall is an American. Any culture/nation can produce a brilliant mind in any discipline. I'm interested in averages.

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• ReSharper - Possible Null Assignment when using Microsoft.Contracts

  - by HVS

  Is there any way to indicate to ReSharper that a null reference won't occur because of Design-by-Contract Requires checking? For example, the following code will raise the warning (Possible 'null' assignment to entity marked with 'NotNull' attribute) in ReSharper on lines 7 and 8: private Dictionary<string, string> _Lookup = new Dictionary<string, string>(); public void Foo(string s) { Contract.Requires(!String.IsNullOrEmpty(s)); if (_Lookup.ContainsKey(s)) _Lookup.Remove(s); } What is really odd is that if you remove the Contract.Requires(...) line, the ReSharper message goes away. Update I found the solution through ExternalAnnotations which was also mentioned by Mike below. Here's an example of how to do it for a function in Microsoft.Contracts: Create a directory called Microsoft.Contracts under the ExternalAnnotations ReSharper directory. Next, Create a file called Microsoft.Contracts.xml and populate like so: <assembly name="Microsoft.Contracts"> <member name="M:System.Diagnostics.Contracts.Contract.Requires(System.Boolean)"> <attribute ctor="M:JetBrains.Annotations.AssertionMethodAttribute.#ctor"/> <parameter name="condition"> <attribute ctor="M:JetBrains.Annotations.AssertionConditionAttribute.#ctor(JetBrains.Annotations.AssertionConditionType)"> <argument>0</argument> </attribute> </parameter> </member> </assembly> Restart Visual Studio, and the message goes away!

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• Legacy URL rewriting with query string parameters

  - by John Kaster

  I've looked at http://stackoverflow.com/questions/817325/asp-net-mvc-routing-legacy-urls-passing-querystring-ids-to-controller-actions and several other similar posts for legacy URL routing, but I can't get past the error "The RouteData must contain an item named 'controller' with a non-empty string value." Looking this up on line didn't give me any hints to solve my problem. I've implemented the Legacy routing class described in the link above, and this is what I've defined in the routing table: routes.Add( "Legacy", new LegacyRoute("fooref.aspx", "FooRef", new LegacyRouteHandler()) ); routes.MapRoute( "FooRef", "{controller}/{action}", new { controller = "Home", action = "Index", foo_id = UrlParameter.Optional, bar_id = UrlParameter.Optional } ); When I use Phil Haack's route debugger, it indicates that fooref.aspx has a match, but when I turn the route debugger off, I get the error above. If I reverse the statement order, I get "Resource not found" for /ctprefer.aspx, which makes sense -- so it appears to be finding that as a valid route when put in the other order. Where do I need to declare this missing controller reference? Have routing requirements changed for ASP.NET MVC 2 RTM?

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• Problems with MediaRecorder class setting audio source - setAudioSource() - unsupported parameter

  - by arakn0

  Hello everybody, I'm new in Android development and I have the next question/problem. I'm playing around with the MediaRecorder class to record just audio from the microphone. I'm following the steps indicated in the official site: http://developer.android.com/reference/android/media/MediaRecorder.html So I have a method that initializes and configure the MediaRecorder object in order to start recording. Here you have the code: this.mr = new MediaRecorder(); this.mr.setAudioSource(MediaRecorder.AudioSource.MIC); this.mr.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP); this.mr.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB); this.mr.setOutputFile(this.path + this.fileName); try { this.mr.prepare(); } catch (IllegalStateException e) { Log.d("Syso", e.toString()); e.printStackTrace(); } catch (IOException e) { Log.d("Syso", e.toString()); e.printStackTrace(); } When I execute this code in the simulator, thanks to logcat, I can see that the method setAudioSource(MediaRecorder.AudioSource.MIC) gives the next error (with the tag audio_ipunt) when it is called: ERROR/audio_input(34): unsupported parameter: x-pvmf/media-input-node/cap-config-interface;valtype=key_specific_value ERROR/audio_input(34): VerifyAndSetParameter failed And then when the method prepare() is called, I get the another error again: ERROR/PVOMXEncNode(34): PVMFOMXEncNode-Audio_AMRNB::DoPrepare(): Got Component OMX.PV.amrencnb handle If I start to record bycalling the method start()... I get lots of messages saying: AudioFlinger(34):RecordThread: buffer overflow Then...after stop and release,.... I can see that a file has been created, but it doesn't seem that it been well recorderd. Anway, if i try this in a real device I can record with no problems, but I CAN'T play what I just recorded. I gues that the key is in these errors that I've mentioned before. How can I fix them? Any suggestion or help?? Thanks in advanced!!

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• Problem deleting record using Entity Framework and System.Data.SQLite

  - by jamone

  I have a SQLite DB that is set up so when I delete a Person the delete is cascaded. This works fine when I manually delete a Person (all records that reference the PersonID are deleted). But when I use Entity Framework to delete the Person I get an error: System.InvalidOperationException: The operation failed: The relationship could not be changed because one or more of the foreign-key properties is non-nullable. When a change is made to a relationship, the related foreign-key property is set to a null value. If the foreign-key does not support null values, a new relationship must be defined, the foreign-key property must be assigned another non-null value, or the unrelated object must be deleted. I don't understand why this is occurring. My trigger is set to clean up all related objects before deleting the object it was told to delete. When I go into the model editor and check the properties of the relationship it shows no action for the OnDelete property. Why isn't this set correctly by pulling it from the DB? Here's the relivent SQL for my tables. CREATE TABLE [SomeTable] ( [SomeTableID] INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT, [PersonID] INTEGER NOT NULL REFERENCES [Person](PersonID) ON DELETE CASCADE ) CREATE TABLE [Person] ( [PersonID] INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT )

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• System.IO.FileLoadException

  - by Raj G

  Hi All, I have got this error when using Enterprise Library 3.1 May 2007 version. We are developing a product and have a common lib directory beneath the Subversion Trunk directory <\Trunk\Lib\ into which we put all the third party DLLs. Inside this we have Microsoft\EnterpriseLibrary\v3.1 in which we have copied all the dlls from \Program Files\Microsoft Enterprise Library May2007\bin. Everything was working properly until one of the developers installed the source code on this machine. There were some dlls copied at the end of the source code installation and once that was done, he is not able to run the project anymore. He always gets this error 'Microsoft.Practices.EnterpriseLibrary.Data, Version=3.1.0.0, Culture=neutral, PublicKeyToken=null' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)' What is the problem here? I thought that when the source code was installed it was just supposed to build everything and copy in the bin directory within the source code parent directory. Also we have copied the Dlls from Microsoft Enterprise Library May 2007\bin directory into our product development directory and references into our project with a copylocal flag set to true. Can anyone help me out here RK

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• Could not convert JavaScript argument arg 0" nsresult: "0x80570009 (NS_ERROR_XPC_BAD_CONVERT_JS

  - by Drahcir

  I am trying to make this captcha jquery plugin to work. The a certain line of code is executed, the error pops up. This is the line of code that causes the error : $(".ajax-fc-" + rand).draggable({ containment: '#ajax-fc-content' }); What I am assuming is that there is some kind of conflict with the javascript reference, but can't determain what. These are the referenes that I am using <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.3.2/jquery.min.js"></script> <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.7.2/jquery-ui.min.js"></script> <script src="js/ui.core.js"></script> <script src="js/ui.draggable.js"></script> <script src="js/ui.droppable.js"></script> <script src="js/effects.core.js"></script> <script src="js/effects.slide.js"></script>

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• How to implement facebook like button

  - by vamsivanka

  I am trying to implement facebook like button on my website. The first four lines in the code is already there on my site after the end of the "" tag. To implement the "Like button" i have added the second script (Line five to the end) and ran the application. Its giving me an error as "Microsoft Jscript runtime error:'_onLoad' is null or not an object" Please Let me know. Thanks <script type="text/javascript" src="http://static.ak.connect.facebook.com/js/api_lib/v0.4/FeatureLoader.js.php"></script> <script type="text/javascript"> FB.init("myapikey", "xd_receiver.htm", { "reloadIfSessionStateChanged": true }); </script> <script type="text/javascript"> window.fbAsyncInit = function() { FB.init({appId: 'myappid', status: true, cookie: true, xfbml: true}); }; (function() { var e = document.createElement('script'); e.async = true; e.src = document.location.protocol + '//connect.facebook.net/en_US/all.js'; document.getElementById('fb-root').appendChild(e); }()); </script> References: http://developers.facebook.com/docs/reference/plugins/like <fb:like href="http://webclip.in" layout="standard" show-faces="true" width="450" action="like" font="arial" colorscheme="light"/>

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• Another BC30002: Type is not defined.

  - by brett

  Here's what I've done... I used wsdl.exe to create a .cs class for my wsdl service connection. I made a Visual Studio project to compile the .cs into a dll having namespace CalculatorService (CalculatorService.dll). Successful thus far. I created an asp.net project added my namespace import: %@ Import Namespace="CalculatorService" % I right-clicked on the project, clicked Add Reference, found my .dll, added it, built the project, checked /bin to ensure my dll was there (and it was). % 'I called the namespace:' Dim calcService As New CalculatorService.CalculatorService() 'called the function from the service' Dim xmlResult = calcService.GetSVS_ItemTable_XML("", "", "", "", "", "") 'printed the result' Response.Write(xmlResult) % All is well LOCALLY while debugging. It found the CalculatorService, connected to it, got the XML and displayed it. I then wanted to put it on the web so I built and published my project: under "Copy" - Only files needed to run this application...selected! Deploying on the web says Type 'CalculatorService.CalculatorService' is not defined. Here is a link to the live script: http://vansmith.com/_iaps.wsdl/pub/Default.aspx Any ideas?

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• Installing MonoTouch - ibtool not found error

  - by Nic Wise

  I've had Xcode (3.2.1 - SnowLeopard, iphone 3.1.3) installed for a while, and I can run and build apps on it fine. I installed MonoTouch, as I want to leverage the 8+ years of .NET skills I have :) So I installed: Mono: MonoFramework-2.6.1_1.macos10.novell.x86 MonoTouch: monotouch-eval-1.5.0 MonoDevelop: MonoDevelop-2.2.1-r152508 (was 2.2.1, but when I started it up, it said there was an update, which I installed - thats the update version) If I make a new project and build it, I get any of the following errors: Build failed. Object reference not set to the instance of an object. Build failed: ibtool not found (btw, it's in /Developer/usr/bin/ibtool) or a similar one to the second one if I use the older (2.2.1 released) version of MonoTouch. I can't find any debug info anywhere. I could reinstall XCode/iPhone SDK, but as it already is installed and works (and no, this isn't a SL upgrade), it doesn't make sense. Anyone got any ideas? I SO want to use MonoTouch - Obj-C drives me up the wall! Console apps (mono ones) work fine. Mac OS X 10.6.2, Macbook Pro, clean install with old settings moved over.

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• ListView item background via custom selector

  - by Gil

  Is it possible to apply a custom background to each Listview item via the list selector? The default selector specifies @android:color/transparent for the state_focused="false" case, but changing this to some custom drawable doesn't affect items that aren't selected. Romain Guy seems to suggest in this answer that this is possible. I'm currently achieving the same affect by using a custom background on each view and hiding it when the item is selected/focused/whatever so the selector is shown, but it'd be more elegant to have this all defined in one place. For reference, this is the selector I'm using to try and get this working: <selector xmlns:android="http://schemas.android.com/apk/res/android"> <item android:state_focused="false" android:drawable="@drawable/list_item_gradient" /> <!-- Even though these two point to the same resource, have two states so the drawable will invalidate itself when coming out of pressed state. --> <item android:state_focused="true" android:state_enabled="false" android:state_pressed="true" android:drawable="@drawable/list_selector_background_disabled" /> <item android:state_focused="true" android:state_enabled="false" android:drawable="@drawable/list_selector_background_disabled" /> <item android:state_focused="true" android:state_pressed="true" android:drawable="@drawable/list_selector_background_transition" /> <item android:state_focused="false" android:state_pressed="true" android:drawable="@drawable/list_selector_background_transition" /> <item android:state_focused="true" android:drawable="@drawable/list_selector_background_focus" /> </selector> And this is how I'm setting the selector: <ListView android:id="@android:id/list" android:layout_width="fill_parent" android:layout_height="fill_parent" android:listSelector="@drawable/list_selector_background" /> Thanks in advance for any help!

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• ArgumentError: Error #2004: One of the parameters is invalid.

  - by Florian

  I got the following stack trace while running a piece of code in my flex application: ArgumentError: Error #2004: One of the parameters is invalid. at ObjectOutput/writeObject() at mx.collections::ArrayList/writeExternal()[C:\autobuild\galaga\frameworks\projects\framework\src\mx\collections\ArrayList.as:470] at mx.collections::ArrayCollection/writeExternal()[C:\autobuild\galaga\frameworks\projects\framework\src\mx\collections\ArrayCollection.as:144] at flash.utils::ByteArray/writeObject() at mx.utils::ObjectUtil$/copy()[C:\autobuild\galaga\frameworks\projects\framework\src\mx\utils\ObjectUtil.as:100] at components::SettingsHandler/saveOpenNodes()[C:\workspaces\Intranets\UniqueInbox\flex_src\components\SettingsHandler.as:153] at components::soapjira/getIssuesByFilters()[C:\workspaces\Intranets\UniqueInbox\flex_src\components\soapjira.as:295] at components.tabs::JiraAllActions/loadData()[C:\workspaces\Intranets\UniqueInbox\flex_src\components\tabs\JiraAllActions.mxml:193] at components::SettingsHandler/settingsClosed()[C:\workspaces\Intranets\UniqueInbox\flex_src\components\SettingsHandler.as:114] at flash.events::EventDispatcher/dispatchEventFunction() at flash.events::EventDispatcher/dispatchEvent() at mx.core::UIComponent/dispatchEvent()[C:\autobuild\galaga\frameworks\projects\framework\src\mx\core\UIComponent.as:9408] at components.general::JiraSettings/closeSettings()[C:\workspaces\Intranets\UniqueInbox\flex_src\components\general\JiraSettings.mxml:58] at components.general::JiraSettings/__save_click()[C:\workspaces\Intranets\UniqueInbox\flex_src\components\general\JiraSettings.mxml:107] That stack comes up when running the following line (SettingsHandler.as:153): var tmp:Object = parentComponent.dataGrid.dataProvider.openNodes; I am actually copying the open nodes of a datagrid's provider. Has been working until now and just started going wrong, no idea what I have changed that could interfere with this. On debug mode, I see that openNodes is accessible and contains the open nodes, as expected. Doing tmp:Object = parentComponent.dataGrid.dataProvider.openNodes works, but not with ObjectUtil. (parentComponent is the reference to the component which contains the DG).

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• JSON-RPC and Json-rpc service discovery specifications

  - by Artyom

  Hello, I'm going to implement JSON-PRC web service. I need specifications for this. So far I had found only one resource that can be called as real specifications: JSON-RPC 1.0 http://json-rpc.org/wiki/specification Proposal of JSON-PRC 2.0: http://groups.google.com/group/json-rpc/web/json-rpc-2-0 (why is it on google groups?) However I've seen that JavaScript frameworks like Dojo actively use JSON-RPC SMD Service Mapping Description proposal But it requires JSON Schema specifications, but it redirects to incorrect URL as reference. So far I had found following: http://tools.ietf.org/html/draft-zyp-json-schema-02 And it is still draft... Can anybody point me to some actual specifications... At least something official updated? Because it looks like that implementing JSON-RPC 1.0 as is may be not enough, at least for frameworks like Dojo. Or am I wrong? Questions: Would implementation of JSON-RPC 1.0 specifications be enough to provide JSON-RPC service for most of modern clients, and how many clients there (if at-all) that actually support beyond JSON-RPC 1.0 capabilities (SMD, Schema, 2.0)? Because it looks like that JSON-RPC 1.0 is only one that has official specifications (and not draft) If I should implement SMD, or it is recommended can somebody point to official, most recent specifications of Json Schema and Service Mapping Description or links I found are really "the specifications?" Are JSON-RPC 2.0, SMD and JSON-Schema drafts stable enough to implement them? Note: do not suggest existing JSON-RPC service implementations. Anybody?

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• pointPolygonTest in OpenCV 2.2

  - by Mathieu Dubois

  I wanted to use pointPolygonTest but I have a problem. I'm stuck to OpenCV2.2. I tried to use the code found here: http://docs.opencv.org/doc/tutorials/imgproc/shapedescriptors/point_polygon_test/point_polygon_test.html#point-polygon-test I use findContours to detect contours in an image. Under OpenCV 2.2 returns a vector< vector<Point> >. The problem is that pointPolygonTest accept a matrix as an entry. Therefore the code doesn't compile with OpenCV 2.2: erreur: invalid initialization of reference of type ‘const cv::Mat&’ from expression of type ‘std::vector<cv::Point_<int>, std::allocator<cv::Point_<int> > >’ Under more recent OpenCV versions, the findContours function returns vector<Mat> so it's easy to pass to pointPolygonTest (see the example). I guess I could convert the vector< vector<Point> > to vector<Mat>. Unfortunately the documentation is not very clear about the format. Does anybody have an advice?

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• WIX Merge Module : Trying to use $(var.Project.TargetFileName)

  - by Stephen Bailey

  I have created a simple Wix 3 Merge Module in VS 2005 ( .wxs ) <?xml version="1.0" encoding="UTF-8"?> <Wix xmlns="http://schemas.microsoft.com/wix/2006/wi"> <Module Id="TestMergeModule" Language="1033" Version="1.0.0.0"> <Package Id="ef2a568e-a8db-4213-a211-9261c26031aa" Manufacturer="Me" InstallerVersion="200" /> <Directory Id="TARGETDIR" Name="SourceDir"> <Directory Id="MergeRedirectFolder"> <Component Id="Test_ModuleComponent" Guid="{1081C5BC-106E-4b89-B14F-FFA71B0987E1}"> <File Id="Test" Name="$(var.Project.TargetFileName)" Source="$(var.Project.TargetPath)" DiskId="1" /> </Component> </Directory> </Directory> </Module> </Wix> And I have added the project "Project" as a reference to this Merge Module, however I continue to get this error Error 7 Undefined preprocessor variable '$(var.Project.TargetFileName)'. Any suggestions, I am sure I am just missing the obvious here.

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• Fluent NHibernate is bringing ClassMap Id and SubClassMap Id to referenced table?

  - by Andy

  HI, I have the following entities I'm trying to map: public class Product { public int ProductId { get; private set; } public string Name { get; set; } } public class SpecialProduct : Product { public ICollection<Option> Options { get; private set; } } public class Option { public int OptionId { get; private set; } } And the following mappings: public class ProductMap : ClassMap<Product> { public ProductMap() { Id( x => x.ProductId ); Map( x => x.Name ); } public class SpecialProductMap : SubclassMap<SpecialProduct> { public SpecialProductMap() { Extends<ProductMap>(); HasMany( p => p.Options ).AsSet().Cascade.SaveUpdate(); } } public class OptionMap : ClassMap<Option> { public OptionMap() { Id( x => x.OptionId ); } } The problem is that my tables end up like this: Product -------- ProductId Name SpecialProduct -------------- ProductId Option ------------ OptionId ProductId // This is wrong SpecialProductId // This is wrong There should only be the one ProductId and single reference to the SpecialProduct table, but we get "both" Ids and two references to SpecialProduct.ProductId. Any ideas? Thanks Andy

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• Reattaching an object graph to an EntityContext: "cannot track multiple objects with the same key"

  - by dkr88

  Can EF really be this bad? Maybe... Let's say I have a fully loaded, disconnected object graph that looks like this: myReport = {Report} {ReportEdit {User: "JohnDoe"}} {ReportEdit {User: "JohnDoe"}} Basically a report with 2 edits that were done by the same user. And then I do this: EntityContext.Attach(myReport); InvalidOperationException: An object with the same key already exists in the ObjectStateManager. The ObjectStateManager cannot track multiple objects with the same key. Why? Because the EF is trying to attach the {User: "JohnDoe"} entity TWICE. This will work: myReport = {Report} {ReportEdit {User: "JohnDoe"}} EntityContext.Attach(myReport); No problems here because the {User: "JohnDoe"} entity only appears in the object graph once. What's more, since you can't control how the EF attaches an entity, there is no way to stop it from attaching the entire object graph. So really if you want to reattach a complex entity that contains more than one reference to the same entity... well, good luck. At least that's how it looks to me. Any comments? UPDATE: Added sample code: // Load the report Report theReport; using (var context1 = new TestEntities()) { context1.Reports.MergeOption = MergeOption.NoTracking; theReport = (from r in context1.Reports.Include("ReportEdits.User") where r.Id == reportId select r).First(); } // theReport looks like this: // {Report[Id=1]} // {ReportEdit[Id=1] {User[Id=1,Name="John Doe"]} // {ReportEdit[Id=2] {User[Id=1,Name="John Doe"]} // Try to re-attach the report object graph using (var context2 = new TestEntities()) { context2.Attach(theReport); // InvalidOperationException }

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• Ideas for OpenSource CMS in ASP.NET MVC

  - by rajesh pillai

  I am in the process of collecting ideas for building an opensource CMS based on ASP.net framework. I have choosen ASP.NET MVC with Jquery as the tool to develop this. I have made this as community wiki. Background: Most of the good CMS that is available is built on PHP, though off late CMS built on ASP.net framework seems to be cropping up. I would like to collect ideas/suggestion/expectations from an opensource CMS system for ASP.net platform. I am looking for expectation from technology and features that you wish could find in a modern CMS and any other thoughts/ideas that comes to your mind. Your input would be of great help in this direction. Meanwhile I am also reviewing many opensource CMS system built on ASP.net as well as MS Office Sharepoint to get ideas and I would update my findings here for your reference. The following are some of the opensource CMS/BlogEngines that I am in the process of reviewing. -Oxite (ASP.net MVC) : This is the new kid on the block -Wordpress -BlogEngine.net -Umbraco Some of the features that I can think of is noted below Simplified content creation Support Multiple content author Metadata feature Workflow engine Simplified deployment List based contents (sharepoint like) Customizable URL's Support content Caching Roles (contenauthor, contentpublisher etc) Support different types of content (like html, txt, document, image, videos) Skinnable (support extensible themes) Localization & Globalization Unlimited nesting of categories Readymade template for blog, forums,survey. Good documentation You can add your points or add some depth to any of the above feature.

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• Conversion constructor vs. conversion operator: precedence

  - by GRB

  Reading some questions here on SO about conversion operators and constructors got me thinking about the interaction between them, namely when there is an 'ambiguous' call. Consider the following code: class A; class B { public: B(){} B(const A&) //conversion constructor { cout << "called B's conversion constructor" << endl; } }; class A { public: operator B() //conversion operator { cout << "called A's conversion operator" << endl; return B(); } }; int main() { B b = A(); //what should be called here? apparently, A::operator B() return 0; } The above code displays "called A's conversion operator", meaning that the conversion operator is called as opposed to the constructor. If you remove/comment out the operator B() code from A, the compiler will happily switch over to using the constructor instead (with no other changes to the code). My questions are: Since the compiler doesn't consider B b = A(); to be an ambiguous call, there must be some type of precedence at work here. Where exactly is this precedence established? (a reference/quote from the C++ standard would be appreciated) From an object-oriented philosophical standpoint, is this the way the code should behave? Who knows more about how an A object should become a B object, A or B? According to C++, the answer is A -- is there anything in object-oriented practice that suggests this should be the case? To me personally, it would make sense either way, so I'm interested to know how the choice was made. Thanks in advance

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• ASP.NET MVC async call a WCF service.

  - by mmcteam

  Hi all. After complete of asynchronous call to WCF service I want set success message into session and show user the notification . I tried use two ways for complete this operation. 1) Event Based Model. client.GetDataCompleted += new EventHandler<GetDataCompletedEventArgs>(GetDataCompleted); client.GetDataAsync(id, client); private void GetDataCompleted(object obj, GetDataCompletedEventArgs e) { this.SetNotification(new Notification() { Message = e.Result, Type = NotificationType.Success }); } In MyOperationCompleted event i can set notification to HttpContext.Current.Session, but I must waiting before this operation will completed and can't navigate to others pages. 2) IAsyncResult Model. client.BeginGetData(id, GetDataCallback, client); private void GetDataCallback(IAsyncResult ar) { string name = ((ServiceReference1.Service1Client)ar.AsyncState).EndGetData(ar); this.SetNotification(new Notification() { Message = name, Type = NotificationType.Success }); } "Generate asynchronous operations" in service reference enabled. Please help me with this trouble. I novice in ASP.NET MVC. Thanks.

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• Populating Models from other Models in Django?

  - by JT

  This is somewhat related to the question posed in this question but I'm trying to do this with an abstract base class. For the purposes of this example lets use these models: class Comic(models.Model): name = models.CharField(max_length=20) desc = models.CharField(max_length=100) volume = models.IntegerField() ... <50 other things that make up a Comic> class Meta: abstract = True class InkedComic(Comic): lines = models.IntegerField() class ColoredComic(Comic): colored = models.BooleanField(default=False) In the view lets say we get a reference to an InkedComic id since the tracer, err I mean, inker is done drawing the lines and it's time to add color. Once the view has added all the color we want to save a ColoredComic to the db. Obviously we could do inked = InkedComic.object.get(pk=ink_id) colored = ColoredComic() colored.name = inked.name etc, etc. But really it'd be nice to do: colored = ColoredComic(inked_comic=inked) colored.colored = True colored.save() I tried to do class ColoredComic(Comic): colored = models.BooleanField(default=False) def __init__(self, inked_comic = False, *args, **kwargs): super(ColoredComic, self).__init__(*args, **kwargs) if inked_comic: self.__dict__.update(inked_comic.__dict__) self.__dict__.update({'id': None}) # Remove pk field value but it turns out the ColoredComic.objects.get(pk=1) call sticks the pk into the inked_comic keyword, which is obviously not intended. (and actually results in a int does not have a dict exception) My brain is fried at this point, am I missing something obvious, or is there a better way to do this?

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• Why is EXC_BAD_ACCESS so unhelpful?

  - by Dustin

  First let me say I come from a background in Flash/AS3, which I realize is not as strict about most things as iPhone/Objective-C. I suspect my question actually applies to AS3 as well, but let me ask it as pertaining to Obj-c. Why is the error EXC_BAD_ACCESS, and others like it, so unhelpful? I realize that it normally means mismanagement of memory somewhere, but why can't it tell you more about the problem. For instance why doesn't it say "EXC_BAD_ACCESS, you tried to pass pointer suchAndSuch on line 123, however you're an idiot, because you released it on line 69 so it's not available anymore"? I realize I can use the debugger to get more clues about where my error occurred, but many times this is only marginally helpful. For instance sometimes none of the messages in the stack/thread/whatever are even my code. Other times it is my code but on the top of the stack will be a message that has 4+ parameters, ok thanks debugger you narrowed it down to 4 possible pointers by why can't you just tell me which one!? I'm guessing there's just some fundamental explanation that I missed because of the background I came from, not needing to worry about memory and such. Although there is an error that can happen a lot in AS3 development that is equally mysterious and along the same lines. "Error #1009: Cannot access a property or method of a null object reference" which almost always means a variable you were expecting to be holding something is actually null. Why doesn't it tell me WHICH variable?!

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• Full JSON-RPC specifications

  - by Artyom

  Hello, I'm going to implement JSON-PRC web service. I need specifications for this. So far I had found only one resource that can be called as real specifications: JSON-RPC 1.0 http://json-rpc.org/wiki/specification Proposal of JSON-PRC 2.0: http://groups.google.com/group/json-rpc/web/json-rpc-2-0 (why is it on google groups?) However I've seen that JavaScript frameworks like Dojo actively use JSON-RPC SMD Service Mapping Description proposal But it requires JSON Schema specifications, but it redirects to incorrect URL as reference. So far I had found following: http://tools.ietf.org/html/draft-zyp-json-schema-02 And it is still draft... Can anybody point me to spome actual specifications... At least something official updated? Because it looks like that implementing JSON-RPC 1.0 and 2.0 would not be enought, at least for frameworks like Dojo. Or am I wrong? Questions: Is it enough to implement JSON-RPC 1.0 specifications and 2.0 draft to be on safe side, would this work for most JSON-RPC clients? If I should implement SMD, or it is recommended can somebody point to official specifications of Json Schema and Service Mapping Description or links I found are really "specifications?" Note: do not suggest existing JSON-RPC service implementations.

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• Correct way to import Blueprint's ie.css via DotLess in a Spark view

  - by Chris F

  I am using the Spark View Engine for ASP.NET MVC2 and trying to use Blueprint CSS. The quick guide to Blueprint says to add links to the css files like so: <link rel="stylesheet" href="blueprint/screen.css" type="text/css" media="screen, projection"> <link rel="stylesheet" href="blueprint/print.css" type="text/css" media="print"> <!--[if lt IE 8]><link rel="stylesheet" href="blueprint/ie.css" type="text/css" media="screen, projection"><![endif]--> But I'm using DotLess and wish to simplify Blueprint as suggested here. So I'm doing this in my site.less (which gets compiled to site.min.css by Chirpy): @import "screen.css"; #header { #title { .span-10; .column; } } ... Now my site can just reference site.min.css and it includes blueprint's screen.css, which includes my reset. I can also tack on an @import "print.css" after my @import "screen.css" if desired. But now, I'm trying to figure out the best way to bring in the ie.css file to have Blueprint render correctly in IE6 & IE7. In my Spark setup, I have a partial called _Styles.spark that is brought into the Application.spark and is passed a view model that includes the filenames for all stylesheets to include (and an HtmlExtension to get the full path) and they're added using an "each" iterator. <link each="var styleSheet in Model.Styles" href="${Html.Stylesheet(styleSheet)}" rel="stylesheet" type="text/css" media="all"/> Should I simply put this below the above line in my _Styles.spark file? <!--[if lt IE 8]><link rel="stylesheet" href="${Html.Stylesheet("ie.css")}" type="text/css" media="screen, projection"><![endif]--> Will Spark even process it because it's surrounded by a comment?

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• "The name 'WithTable' does not exist in the current context" using Fluent NHibernate

  - by Byron Sommardahl

  Might be a really easy problem to fix, but it the solution is eluding me! I'm using Fluent NHibernate 1.0 RTM (and using NHibernate bins that ships with it). I'm trying to map my entities and cannot use the WithTable() method. It's not available in Intelligence and VS doesn't suggest any namespaces to reference. Here's my code: using System; using System.Collections.Generic; using System.Linq; using System.Text; using GeoCodeThe.Net.Domain.Entities; using FluentNHibernate.Mapping; namespace GeoCodeThe.Net.Domain.Mappings { class CategoryMap: ClassMap<ICategory> { public CategoryMap() { WithTable("Categories"); // <----- Compile error: The name 'WithTable' does not exist in the current context Id(x => x.Id); Map(x => x.Name); Map(x => x.Tags); } } My bin folder has: Antlr3.Runtime.dll Castle.Core.dll Castle.DynamicProxy2.dll FluentNHibernate.dll Iesi.Collections.dll log4net.dll NHibernate.ByteCode.Castle.dll NHibernate.dll FluentNHibernate.pdb Castle.Core.xml Castle.DynamicProxy2.xml FluentNHibernate.xml Iesi.Collections.xml log4net.xml NHibernate.ByteCode.Castle.xml NHibernate.xml Any clue what I'm missing? Let me know if you need any more clarification.

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