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  • In C#: How to declare a generic Dictionary with a type as key and an enumeration of that type as val

    - by Marcel
    Hi all, I want to declare a dictionary that stores typed IEnumerable's of a specific type, with that exact type as key, like so: (Edited to follow johny g's comment) private IDictionary<Type, IEnumerable<T>> _dataOfType where T: BaseClass; //does not compile! The concrete classes I want to store, all derive from BaseClass, therefore the idea to use it as constraint. The compiler complains that it expects a semicolon after the member name. If it would work, I would expect this would make the later retrieval from the dictionary simple like: IEnumerable<ConcreteData> concreteData; _sitesOfType.TryGetValue(typeof(ConcreteType), out concreteData); How to define such a dictionary?

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  • How do I map repeating columns in NHibernate without creating duplicate properties

    - by Ian Oakes
    Given a database that has numerous repeating columns used for auditing and versioning, what is the best way to model it using NHibernate, without having to repeat each of the columns in each of the classes in the domain model? Every table in the database repeats these same nine columns, the names and types are identical and I don't want to replicate it in the domain model. I have read the docs and I saw the section on inheritance mapping but I couldn't see how to make it work in this scenario. This seems like a common scenario because nearly every database I've work on has had the four common audit columns (CreatedBy, CreateDate, UpdatedBy, UpdateDate) in nearly every table. This database is no different except that it introduces another five columns which are common to every table.

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  • WPF DrawingVisual from my own class

    - by Robbskinizer
    Hi, Im trying to create my own class which contains a DrawingVisual, something like this public class MyObject { public DrawingVisual visual; public bool faceup; public bool flipped; } I have a drag and drop from a listview to a canvas, but when I try to get the object which back from the Canvas i only get the visual, not any of the other stuff in the class. How do i save "objects" and retreive it from a canvas? Im using my own MyCanvas which inheritance from Canvas, and using the AddVisualChild & AddLogicalChild etc. // Robbin

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  • Using the JNotify library, how can you tell if a deleted file was a file or a directory?

    - by Moeri
    For those unfamiliar with JNotify, this is a library which provides an easy way to monitor events in a directory. For instance, when a file gets deleted in the selected folder, the method "fileDeleted" gets called, along with a few parameters. Here's an example of the fileDeleted method: public void fileDeleted(int wd, String rootPath, String name) { print("deleted " + rootPath + " : " + name); } Now, I would like to know if the deleted file was a file or directory. My usual approach is to create a new File object with the given path, and use the methods isFile() and isDirectory() However, since this file is already deleted, these methods always return false. So here's my concrete question: I have the path to a deleted file or directory, how can I tell wether it was a file or a directory? Is there a workaround to this? What's the best practice to do here? Thank you in advance.

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  • VS 2010 Entity Repository Error

    - by Steve
    In my project I have it set up so that all the tables in the DB has the property "id" and then I have the entity objects inherit from the EntityBase class using a repository pattern. I then set the inheritance modifier for "id" property in the dbml file o/r designer to "overrides" Public MustInherit Class EntityBase MustOverride Property id() As Integer End Class Public MustInherit Class RepositoryBase(Of T As EntityBase) Protected _Db As New DataClasses1DataContext Public Function GetById(ByVal Id As Integer) As T Return (From a In _Db.GetTable(Of T)() Where a.id = Id).SingleOrDefault End Function End Class Partial Public Class Entity1 Inherits EntityBase End Class Public Class TestRepository Inherits RepositoryBase(Of Entity1) End Class the line Return (From a In _Db.GetTable(Of T)() Where a.id = Id).SingleOrDefault however produces the error "Class member EntityBase.id is unmapped" when i use VS 2010 using the 4.0 framework but I never received that error with the old one. Any help would be greatly appreciated. Thanks in advance.

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  • Undefined behaviour with non-virtual destructors - is it a real-world issue?

    - by Roddy
    Consider the following code: class A { public: A() {} ~A() {} }; class B: public A { B() {} ~B() {} }; A* b = new B; delete b; // undefined behaviour My understanding is that the C++ standard says that deleting b is undefined behaviour - ie, anything could happen. But, in the real world, my experience is that ~A() is always invoked, and the memory is correctly freed. if B introduces any class members with their own destructors, they won't get invoked, but I'm only interested in the simple kind of case above, where inheritance is used maybe to fix a bug in one class method for which source code is unavailable. Obviously this isn't going to be what you want in non-trivial cases, but it is at least consistent. Are you aware of any C++ implementation where the above does NOT happen, for the code shown?

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  • When is C++ covariance the best solution?

    - by Neil Butterworth
    This question was asked here a few hours ago and made me realise that I have never actually used covariant return types in my own code. For those not sure what covariance is, it's allowing the return type of (typically) virtual functions to differ provided the types are part of the same inheritance hierarchy. For example: struct A { virtual ~A(); virtual A * f(); ... }; struct B : public A { virtual B * f(); ... }; The different return types of the two f() functions are said to be covariant. Older versions of C++ required the return types to be the same, so B would have to look like: struct B : public A { virtual A * f(); ... }; So, my question: Does anyone have a real-world example where covariant return types of virtual functions are required, or produce a superior solution to simply returning a base pointer or reference?

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  • PHP5: restrict access to function to certain classes

    - by Tim
    Is there a way in PHP5 to only allow a certain class or set of classes to call a particular function? For example, let's say I have three classes ("Foo", "Bar", and "Baz"), all with similarly-named methods, and I want Bar to be able to call Foo::foo() but deny Baz the ability to make that call: class Foo { static function foo() { print "foo"; } } class Bar { static function bar() { Foo::foo(); print "bar"; } // Should work } class Baz { static function baz() { Foo::foo; print "baz"; } // Should fail } Foo::foo(); // Should also fail There's not necessarily inheritance between Foo, Bar, and Baz, so the use of protected or similar modifiers won't help; however, the methods aren't necessarily static (I made them so here for the simplicity of the example).

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  • Where's the definitive resource online about how to carry out Agile development?

    - by jdk
    I want to start Agile practices in a team. I'm assuming the information is available for free online about how to specifically carry it out. Online I can locate the manifesto, the alliances and corporations involved but where is the actual central guide or root instruction set about how to do it? (Maybe the practices themselves are more ethereal or subjective than I expect and it's found in multiple places?) Edit to summarize solutions: Agile is a concept so that's what's to be found online about it. However specific processes or methods of Agile development have been created like Scrum and Extreme programming to provide concrete solutions to teams who want to adopt Agile and reap its proposed benefits. Find the shoe (or method) that fits best. Maybe create it. If looking for solutions online to implement Agile development in your organization or for your project, seek out the specific methods too and decide among them.

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  • Enterprise Library Validation Block - Should validation be placed on class or interface?

    - by Robert MacLean
    I am not sure where the best place to put validation (using the Enterprise Library Validation Block) is? Should it be on the class or on the interface? Things that may effect it Validation rules would not be changed in classes which inherit from the interface. Validation rules would not be changed in classes which inherit from the class. Inheritance will occur from the class in most cases - I suspect some fringe cases to inherit from the interface (but I would try and avoid it). The interface main use is for DI which will be done with the Unity block.

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  • command design pattern usage

    - by sagie
    Hi. I've read 3 descriptions of the command design pattern: wikipedia, dofactory and source making. In all of them, the UML shows a relation between the client to the receiver & the concrete command, but no relation to the invoker. But in all 3 examples the client is the one that initiates the invoker and call its Execute method. I think that should be a relation to the invoker as well. Am I missing somthing in here? Maybe even a basic UML knowladge?

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  • How can I use Object Oriented Javascript to interact with HTML Objects

    - by Steve
    I am very new to object orientated javascript, with experience writing gui's in python and java. I am trying to create html tables that I can place in locations throughout a webpage. Each html table would have two css layouts that control if it is selected or not. I can write all of the interaction if I only have one table. It gets confusing when I have multiple tables. I am wondering how to place these tables throughout a blank webpage and then access the tables individually. I think I am having trouble understanding how inheritance and hierarchy works in javascript/html. NOTE: I am not asking how to make a table. I am trying to dynamically create multiple tables and place them throughout a webpage. Then access their css independently and change it (move them to different locations or change the way the look, independently of the other tables).

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  • How can I emulate forward on 404 in jersey?

    - by koppor
    I have a picture on a given URL. The picture might need a referesh. I want to do the freshness-check at the time of the request. Therefore, I coded a jersey resource handling the request on the picture URL. It refreshes the picture on the filesystem if necessary. I do not want to re-code a caching mechansim, but rely on tomcat's implementation. Therefore, I would like to "forward" the request in the internal handler chain. I tried return new Viewable(sb.toString());, but a viewable is not a picture. What return type can I use? I could let the concrete picture reside on another URL and send a 307 (Temporary Redirect). Always sending that as answer seems odd to me. Related question: How to return a PNG image from Jersey REST service method to the browser

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  • possible to show composition relationship in a diagram generated from PHP source code?

    - by ajsie
    i have tested several UML applications for whether they could show composition relationships in the UML diagrams generated form the PHP source code or not, and the result is they can't. i know that this is a typical problem for PHP cause we don't declare a data type when we code, so it's difficult for the UML applications to know if an instance variable is a reference to an object or not. i also tested nWire with the same result. will there never be applications that could show us a complete map over all object relationships more than just inheritance? i think it's a pity that you can't have a good view over all the relationships for an application. cause when i use an open source solution, i always want to know how the objects are related to each other. maybe we could make comments for the instance variable telling the software that this is an reference to an object? but that would mean that the mapping software is using this solution. i feel its a pity nWire/visual paradigm can't give us a complete map:(

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  • Java 7 New Features

    - by John W.
    I have done some good reading on the new java.util.concurrent features being introduced with the java 7 release. For instance, Phaser, TransferQueue and the more exciting Fork Join Framework. I recently saw a power point made by Josh Bloch about even more features that are going to be introduced however that link has been lost. For example I remember one change is being able to build a Map the same way you can build an array for: Map myMap = {"1,Dog","2,Cat"}; and so forth (this may not be 100% correct but the idea is there) Does anyone know of a list or just can name some new things to look forward to? Note: I did see a question asked http://stackoverflow.com/questions/213958/new-features-in-java-7 however it was asked ~2 years ago and I am sure the list of updates are more concrete. Thanks!

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  • StructureMap IoC problem getting the instance in runtime

    - by user274269
    i have 2 concrete types "CategoryFilter" & "StopWordsFilter" that implements "IWordTokensFilter". Below is my setup: ForRequestedType<IWordTokensFilter>().TheDefaultIsConcreteType<CategoryFilter>() .AddInstances(x => { x.OfConcreteType<StopWordsFilter>(); } ); The problem is the run-time when structure map auto inject it on my class, bec. i have arguments with same plugin-type: public ClassA(IWordTokensFilter stopWordsFilter, IWordTokensFilter categoryFilter) i'm always getting CategoryFilter in my first argument but it should be stopWordsFilter. How can i setup this in a right way? thanks in advance

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  • is right to implement a business logic in the type binding DI framwork?

    - by Martino
    public IRedirect FactoryStrategyRedirect() { if (_PasswordExpired) { return _UpdatePasswordRedirectorFactory.Create(); } else { return _DefaultRedirectorFactory.Create(); } } This strategy factory method can be replaced with type binding and when clause: Bind<IRedirect>.To<UpdatePasswordRedirector>.When(c=> c.kernel.get<SomeContext>().PasswordExpired()) Bind<IRedirect>.To<DefaultRedirector>.When(c=> not c.kernel.get<SomeContext>().PasswordExpired()) I wonder which of the two approaches is the more correct. What are the pros and cons. Especially in the case in which the logic is more complex with more variables to test and more concrete classes to return. is right to implement a business logic in the binding?

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  • commad design pattern usage

    - by sagie
    Hi. I've read 3 descriptions of the command design pattern: wikipedia, dofactory and source making. In all of them, the UML shows a relation between the client to the receiver & the concrete command, but no relation to the invoker. But in all 3 examples the client is the one that initiates the invoker and call its Execute method. I think that should be a relation to the invoker as well. Am I missing somthing in here? Maybe even a basic UML knowladge?

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  • Zend router problem

    - by Fluffy
    Hi, folks. I have some problems with zend routes I have shops controller. It has 3 actions(for now): index - lists all of shops using paginator(so I have /shops/?page=2) show - shows concrete shop (show/Apple+store) search - shows search form So now I need to make routing for that. I have followin routes 'shop', new Zend_Controller_Router_Route ('/shops/:title',array('controller' = 'shops', 'action' = 'show'),array('title' = '/^(?!search$).+$/')) 'search_shops',new Zend_Controller_Router_Route_Static ('/shop/search',array('controller' = 'shops', 'action' = 'show')) but when i try to go /shops/Apple+store it says, that there is no Apple store action. If I ommit regexp part on shop route, I can't go to search. What am I doing wrong?

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  • Documented process for using facebook connect for the iPhone to upload photos

    - by Corey Floyd
    After looking I did come accross this post on the facebook forums: link They are feeding the facebook object a UIImage. That seems logical, but where is this documented? The API documentation is generalized to all platforms. Where are the iPhone specific requirements for arguments and their data types? Thanks **Update***** I still have not came across any API docs pertaining to Cocoa. I did, however, gather the information I needed by piecing together forum information, Facebook sample code, and some glue. Hopefully they'll issue something a little more concrete over the next few months.

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  • Understanding reflection

    - by sdmiller
    I recently started work at a new company and a .net web application we have is built using reflection. I have only been out of school for a year and haven't worked with this concept. After studying the code... it looks like there is a single backend interface of type object that has about 20 classes that inherit from it. lots of generic gets and sets On the surface it looks like standard inheritance to me. I guess my question is, what makes this reflection? Is it because the interface is not strongly typed? Thanks

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  • Retlang: What is the best way to unsubscribe from a channel?

    - by TrickyFishy
    I'm not sure what is the best way to unsubscribe from a channel when using Retlang. When you subscribe by calling ISubscriber<T>::Subscribe(...) you are returned an IUnsubscriber. This interface has no methods. Going up a level, IChannel<T> also does not have any methods. The only thing I can think of is casting an ISubscriber<T> to the concrete Channel<T> and calling its Unsubscribe() method or adding an Unsubscribe() method to ISubscriber<T>. I'm just curious if anyone knows what they had in mind before I modify the code.

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  • Erlang Question - Time order of messages

    - by Aiden Bell
    Read (skimmed enough to get coding) through Erlang Programming and Programming Erlang. One question, which is as simple as it sounds: If you have a process Pid1 on machine m1 and a billion million messages are sent to Pid1, are messages handled in parallel by that process (I get the impression no) and(answered below) is there any guarantee of order when processing messages? ie. Received in order sent? If so, how is clock skew handled in high traffic situations for ordering? Coming from the whole C/Thread pools/Shared State background ... I want to get this concrete. I understand distributing an application, but want to ensure the 'raw bones' are what I expect before building processes and distributing workload. Also, am I right in thinking the whole world is currently flicking through Erlang texts ;)

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  • contain new elements of an "instance" in javascript

    - by iamnotmad
    Hi, so I know there are tons of ways to simulate inheritance and other OO features. I have chosen one to use for my project and am wondering if I can create an instance and add stuff to it and keep it contained (within braces). Consider the following: function BaseClass(){ <this.stuff here> } function SubClass(){ this.superClass = BaseClass(); this.superClass(); <this.other stuff here> } myObj = new SubClass(); so myObj is an instance of SubClass. I can add things to myObj like: myObj.blah = "funtimes"; What I would like is to be able to add stuff to the "instance" and keep it organized in braces much like the constructor. psuedo code like: myObj = new SubClass() { var blah = "funtimes" <more instance specific stuff here> } Is something like this possible? Thanks!

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  • How to write function where argument is type but not typed value?

    - by ssp
    I want to convert a string representations of few dozen enum types to enum values. It's easy to convert string to concrete type: Enum.Parse(typeof<FontStyle>,"Bold") |> unbox<FontStyle> but for now i want to write function where type and string are parameters. The best one i can write is: > let s2e (_: 'a) s = Enum.Parse(typeof<'a>,s) |> unbox<'a>;; val s2e : 'a -> string -> 'a > s2e FontStyle.Regular "Bold";; val it : FontStyle = Bold Is there any option to write something like this but with type itself as first argument?

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