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  • Type-aware rendering (and editing) of tabular data in pyqt4

    - by pihentagy
    I would like to have a very short / minimal example of how to create some tabular widget with different types of item in it. In the first round let's say I'd like to render [["Hello", 12, True], ["World", 13, False]] (Hello as string, 12 as number (right-align), True as a checkbox for eg.), but it would be nice to have Dates, Colors, and other type of info. Next round: editing (integer with spinbox, maybe sometimes a combobox is handy, but that may not work out of the box). There must be a simple solution, but I couldn't find...

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  • Haskell: Defaulting constraints to type

    - by yairchu
    Consider this example: applyKTimes :: Integral i => i -> (a -> a) -> a -> a applyKTimes 0 _ x = x applyKTimes k f x = applyKTimes (k-1) f (f x) applyThrice :: (a -> a) -> a -> a applyThrice = applyKTimes 3 The 3 in applyThrice is defaulted by GHC to an Integer as shown when compiling with -Wall: Warning: Defaulting the following constraint(s) to type 'Integer' 'Integral t' arising from a use of 'applyKTimes' So I guess that Integer is the default Integral a => a. Is there a way to define "default types" for other constraints too? Is using default types bad practice? (it does complain when using -Wall..)

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  • How to create custom media type in WordPress?

    - by OJ2
    I have some custom media (special map points for example) I want to associate custom data player with it and place its instances in media library (so them to be accessible in media gallery), keeping possibility to edit it any time user wants to. how to do it? Sorry for my Eng.Lang feel free to edit this Question.

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  • The type{0} does not support direct content - WPF / XAML

    - by Levo
    Hi there: I defined in my code two classes: a "Person" class with public "Age" and "Name" property, and a "People" class that inherits from Generic.List(of T). The code for People class is as followed: Public Class People Inherits Collections.Generic.List(Of Person) ... End Class What I want to achieve is to directly initialize the People class, and add individual Person to it in XAML, i.e.: <local:People x:Key="Familty"> <local:Person Age="11" Name="John" /> <local:Person Age="12" Name="John2" /> ... </local:People> But I keep getting an error in XAML saying: The type 'People' does not support direct content. Any idea as for how to solve this problem? Thank you very much!

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  • Errors when using a Ruby On Rails scaffold with a data type of interger

    - by bublebboy
    I am learning Ruby On Rails. I am on a shared hosting with Ruby version 1.8.1 and Rails version 2.3.10. I am working my way through a tutorial at http://railstutorial.org/chapters/a-demo-app?version=2.3#top and at one point in the tutorial it has me run: script/generate scaffold Micropost content:string user_id:interger The tutorial is using the default database, SQLite3. The command works and I use rake db:migrate to create the database. I can view the page listing the microposts (which is empty), but when I try to add a micropost (microposts/new) I get an error undefined method `user_id' for #<Micropost:0x7f710e4988e8> After doing some testing on my own it seems I experience the problem by using the data type of interger. While I understand that using a scaffold is not the best way of building a ruby on rails, I'm just beginning and would still like to know why I am experiencing this problem to help me better understand how rails works.

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  • PHPUnit test for error thrown with wrong argument type

    - by Spencer Mark
    I'm just starting with PHPUnit and am ok with all assert* methods, but can't figure out how to test for error thrown when the wrong argument is provided to the method - say hinted with array like so: public function(array $list) { } and then tested with null as argument. Could someone please provide an example of how to test for this sort of errors? I've checked quite a few posts on stackoverflow, but couldn't find the answer to this specific issue. Edit Ok - just to give you an idea of what I'm testing - here's the ArrayHelper::removeIfValueIsEmpty() method: public static function removeIfValueIsEmpty(array $array) { if (empty($array)) { return array(); } return array_filter($array, function($value) { return !Helper::isEmpty($value); }); } and now test: class ArrayHelperTest extends PHPUnit_Framework_TestCase { public function testRemoveIfValueIsEmpty() { $this->assertEmpty( \Cmd\Helper\ArrayHelper::removeIfValueIsEmpty(null), '\Cmd\Helper\ArrayHelper::removeIfValueIsEmpty method failed (checking with null as argument)' ); } } This throws an error: PHPUnit_Framework_Error : Argument 1 passed to Cmd\Helper\ArrayHelper::removeIfValueIsEmpty() must be of the type array, null given

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  • Type hinting and optional attributes in PHP

    - by Álvaro G. Vicario
    I have a class method that deals with dates: public function setAvailability(DateTime $start, DateTime $end){ } Since item availability can have lower limit, upper limit, both or none, I'd like to make setAvailability() accept NULL values as well. However, the NULL constant violates the type hinting: $foo->setAvailability(NULL, $end); triggers: Catchable fatal error: Argument 1 passed to Foo::setAvailability() must be an instance of DateTime, null given And, as far as I know, I cannot have a DateTime instance with no value. (Can I?) For a reason I cannot grasp, this seems to work: public function setAvailability(DateTime $start=NULL, DateTime $end=NULL){ } ... $foo->setAvailability(NULL, $end); But it looks like a hack that works by pure chance. How would you deal with unset dates in PHP classes?

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  • Memory management for "id<ProtocolName> variableName" type properties

    - by Malakim
    Hi, I'm having a problem with properties of the following type: id<ProtocolName> variableName; ..... ..... @property (nonatomic, retain) id<ProtocolName> variableName; I can access and use them just fine, but when I try to call [variableName release]; I get compiler warnings: '-release' not found in protocol(s) Do I need to define a release method in the interface, or how do I release the memory reserved for the variable? Thanks!

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  • SimpleInjector - Register a type for all it's interfaces

    - by Karl Cassar
    Is it possible to register a type for all it's implementing interfaces? E.g, I have a: public class Bow : IWeapon { #region IWeapon Members public string Attack() { return "Shooted with a bow"; } #endregion } public class HumanFighter { private readonly IWeapon weapon = null; public HumanFighter(IWeapon weapon) { this.weapon = weapon; } public string Fight() { return this.weapon.Attack(); } } [Test] public void Test2b() { Container container = new Container(); container.RegisterSingle<Bow>(); container.RegisterSingle<HumanFighter>(); // this would match the IWeapon to the Bow, as it // is implemented by Bow var humanFighter1 = container.GetInstance<HumanFighter>(); string s = humanFighter1.Fight(); }

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  • non-scalar type requested

    - by lego69
    can somebody please help me with an error conversion from `A' to non-scalar type `B' requested I have class A and derived from it B, but I have problems with these rows: A a(1); A *pb = new B(a); B b = *pb; //here I have an error thanks in advance for any help class A { protected: int player; public: A(int initPlayer = 0); A(const A&); A& operator=(const A&); virtual ~A(){}; virtual void foo(); void foo() const; operator int(); }; class B: public A { public: B(int initPlayer): A(initPlayer){}; ~B(){}; virtual void foo(); };

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  • C++ Boost bind value type

    - by aaa
    hello. I look in documentation and source code but cannot figure out how to get return value type of boost bind functor. I am trying to accomplish following: 35 template<typename T,size_t N, class F> 36 boost::array<typename F::value_type, N> make_array(T (&input)[N], F unary) { 37 boost::array<typename F::value_type, N> array; 38 std::transform(input, input + N, array.begin(), unary); 39 return array; 40 } where F can be bind functor. the above does not work because functor does not have value_type. for that matter, is there standard interface for unary/binary functor as far as return value. Thanks

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  • Detect all changes to a <input type="text"> (immediately) using JQuery

    - by Dustin Boswell
    There are many ways the value of a <input type="text"> can change, including: keypresses copy/paste modified with JavaScript auto-completed by browser or a toolbar I want my JavaScript function to be called (with the current input value) any time it changes. And I want it to be called right away, not just when the input loses focus. I'm looking for the cleanest and most robust way to do this across all browsers (using jQuery preferably). Example use case: On the Twitter Signup page, the username field's value gets shown in the url "http://twitter/username" below it.

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  • super(type,subclass) in simple singleton implementation

    - by Tianchen Wu
    when I was implementing naive singleton in python, I came up with a problem with super key word. As usual the behavior of super is always tricky and buggy, hope someone can shed light on it. Thanks :) The problem is that: class Singleton(object): def __new__(cls,*args,**kw): if not hasattr(cls,'_instance'): #create a instance of type cls, origin=super(Singleton,Singleton).__new__(cls,*args,**kw) cls._instance=origin return cls._instance class B(Singleton): def __init__(self,b): self.b=b It actually works, but I am wondering Will it be better if I change line 5 to the below, like in most of the books? origin=super(Singleton,cls).__new__(cls,*args,**ks) what's the difference to make?

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  • Unable to type cast <AnonymousType#1> to <WindowsFormsApplication1.Attributes> [ C#3.0 ]

    - by Newbie
    I have List<Attributes> la = new List<Attributes>(); la = (from t in result let t1 = t.AttributeCollection from t2 in t1 where t2.AttributeCode.Equals(attributeType) let t3 = t2.TimeSeriesData from k in t3.ToList() where k.Key.Equals(startDate) && k.Key.Equals(endDate) select new { AttributeCode = attributeType, TimeSeriesData = fn(k.Key, k.Value.ToString()) }).ToList<Attributes>(); I am getting the error: 'System.Collections.Generic.IEnumerable<AnonymousType#1>' does not contain a definition for 'ToList' and the best extension method overload 'System.Linq.Enumerable.ToList<TSource>(System.Collections.Generic.IEnumerable<TSource>)' has some invalid arguments I understood tye error meaning but how to type cast it. I have used var and then iterating over it got the result. But without that any other way by which I can do it? Using C# 3.0 Thanks

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  • How to use a Visual C++ .Net String type as argument in a function

    - by stefangachter
    Probably this is not a difficult question, but I am always a little bit confused on how to treat String type as an argument in Visual C++. I have the following to functions: void function_1(String ^str_1) { str_1 = gcnew String("Test"); } void function_2() { String ^str_2 = nullptr; function_1(str_2); } After calling function_1, str_2 is still equal to null, but what I want to achieve is that str_2 is equal to Test. So, how can I achieve that the content of str_1 is passed to function_2? Thanks for any advice.

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  • SQLite: does data type depend on the quotes?

    - by Septagram
    In SQLite, the datatype of a value is associated with the value itself, not with the column type. So suppose we have a table with an integer primary key "id" and an integer column "some_number". If I do a query like this: INSERT INTO mytable (id, some_number) VALUES (NULL, "1234") Will 123 be inserted as an integer or as string? What consequences it will have later for me, say, when I'm comparing it with other value like "234" (as a number 1234 234, as a string "1234" < "234", right?)?

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  • how to create property of type generic class?

    - by Anish
    public class SelectionList<T> : ObservableCollection<SelectionItem<T>> where T : IComparable<T> { // Code } public class SelectionItem<T> : INotifyPropertyChanged { // Code } I need to create a property which is of the type SelectionList...as follows: public SelectionList<string> Sports { get; set; }. But when I replace string with DataRowView, as public SelectionList<DataRowView> Sports { get; set; }. I am getting error. Please help

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  • session variable not available in global before(:each, :type => :controller)

    - by Rob
    Hi, I'm refactoring some specs, in controller specs I have a before(:each) which sets up things required in the session my before filter is... config.before(:each, :type => :controller) do ... session[:current_user] = @user session[:instance] = @instance ... end @user and @instance are also set in the before(:each) i've just hidden them for readability here I get the following error when running the controller tests undefined method `session' for nil:NilClass I would expect the global before callbacks to have the same things as the ones in the individual tests but I guess maybe they are loaded before the rails environment has been initialised? Thanks

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  • converting tag number to int

    - by Ehtesham Sajed
    i m using Visual C++2008. i've assigned tag value=2 of all buttons from button property(using drag n drop). now i want to make some math calculation with tag value. need to change it in int. what is the default data type tag? i used this code, //code sample if(((int)this-button1-Tag)((int)this-button2-Tag)((int)this-button3-Tag)==50) { ........ //i.e, if tag value of button1*tag value of button2*tag value of button 3==50 then... ........ } generated following run time error on a messegebox An unhandled exception of type 'System.InvalidCastException' occurred in learncpp1.exe Additional information: Specified cast is not valid.

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  • step attribute not working with HTML5 <input type="range"> on Safari

    - by Claudiu
    Are there known issues with range inputs not working fully on Safari? I have the following input element: <input type=?"range" min=?"0" max=?"360" step=?"0.0001" value=?"0">? On Chrome, the input goes according to the step variable. On Safari, it only goes by integer values. Even setting the step to 10 still makes it go by increments of 1. I'm confused because I thought Chrome and Safari both used WebKit.

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  • Linking/Combining Type Classes in Haskell

    - by thegravian
    Say I have two type classes defined as follows that are identical in function but different in names: class Monad m where (>>=) :: m a -> (a -> m b) -> m b return :: a -> m a class PhantomMonad p where pbind :: p a -> (a -> p b) -> p b preturn :: a -> p b Is there a way to tie these two classes together so something that is an instance of PhantomMonad will automatically be an instance of Monad, or will instances for each class have to be explicitly written? Any insight would be most appreciated, thanks!

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  • Why is cakephp form input stored in $this->data and POST data stored in $this->params['form'] ?

    - by spudnik1979
    the cakephp rest tutorial says that post data should be in $this-data, but I am finding that it is not, but instead inside $this-params['form'] However, when using cakephp form helper in a view, the data is in $this-data. Am I correct to have to check both locations in my controller? It just seems a bit of a waste of extra code. Shouldnt the data appear in one place for whether it came from a rest rest requestor or Cakephp form post? ps im using cakephp 1.3

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  • How do I change the class of an object to a subclass of its current class in C++?

    - by Jared P
    I have an array of pointers to a base class, so that I can make those pointers point to (different) subclasses of the base class, but still interact with them. (really only a couple of methods which I made virtual and overloaded) I'm wondering if I can avoid using the pointers, and instead just make an array of the base class, but have some way to set the class to the subclass of my choosing. I know there must be something there specifying the class, as it needs to use that to look up the function pointer for virtual methods. By the way, the subclasses all have the same ivars and layout. Note: the design is actually based on using a template argument instead of a variable, due to performance increases, so really the abstract base class is just the interface for the subclasses, which are all the same except for their compiled code. Thanks

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