Can anyone here identify why the TypeError is being raised at the bottom of this example shown below? >>> import threading >>> class SessionManager(threading.Thread, threading._RLock, dict): UPDATE = 60 * 60 def run(self): while True: time.sleep(self.UPDATE) with self: for key in...
I have a class Parent. I want to define a __new__ for Parent so it does some magic upon instantiation (for why, see footnote). I also want children classes to inherit from this and other classes to get Parent's features. The Parent's __new__ would return an instance of a subclass of the child class's bases and the Parent class. This is ...
How do you deal with having only single inheritance in java? Here is my specific problem: I have three (simplified) classes: public abstract class AbstractWord{ String kind; // eg noun, verb, etc public String getKind(){ return kind; } } public class Word extends AbstractWord{ public final String word; ctor... ...
I'm writing some code involving inheritance from a basic ref-counting pointer class; and some intricacies of C++ popped up. I've reduced it as follows: Suppose I have: class A{}; class B{}; class C: public A, public B {}; C c; C* pc = &c; B* pb = &c; A* pa = &c; // does pa point to a valid A object? // does pb point to a valid B obje...
Possible Duplicate: C++ pointer multi-inheritance fun. (Follow up on: http://stackoverflow.com/questions/2157104/c-pointer-multi-inheritance-fun ) I'm writing some code involving inheritance from a basic ref-counting pointer class; and some intricacies of C++ popped up. I've reduced it as follows: Suppose I have: class A{in...
Possible Duplicates: C++ pointer multi-inheritance fun. more c++ multiple inheritance fun This is a problem that arose from dealing with ref-counted pointer base class and threading fun. Given: class A{int x, y;}; class B{int xx, yy;}; class C: public A, public B {int z;}; C c; C* pc = &c; B* pb = CtoB(pc); A* pa = CtoA(pc...
Given the following code class T { public: virtual ~T () {} virtual void foo () = 0; }; class U { public: U() {} ~U() {} void bar () { std::cout << "bar" << std::endl; } }; class A : public U, public T { public: void foo () { std::cout << "foo" << std::endl; } }; int main ()...
In the followint code, how does the pointer conversion & multi-inheritance play together? class Foo { public: virtual void someFunc(); }; class Bar; void someWork(Bar *bar) { ((Foo*) bar)->someFunc(); } class Bar: public Zed, public Foo { ... virtual void someFunc() { ... do something else ... } } Bar bar; int main() { som...
I have doubt whether we can achieve multiple inheritence using 'module' concept or Is there any other keywords or concepts which achieve multiple inheritence in ruby? ...
Hello Folks I have a class ImageA, and a class ImageB. The both classes represents an image in my app, but each one in a different way. Even being different, their constructors are equal, and both have the method compare. So, what I done was creating a class Image, and ImageA and ImageB are subClasses of Image. public abstract class I...
Hi, i have two questions converning metaclasses and multiple inheritance. The first is: Why do i get a TypeError for the class Derived but not for Derived2? class Metaclass(type): pass class Klass(object): __metaclass__ = Metaclass #class Derived(object, Klass): pass # if I uncomment this, I get a TypeError class OtherClass(ob...
Suppose I have a diamond inheritance situation as follows: class A{ public: virtual void foo(){}; }; class B: public virtual A{ public: virtual void foo(){}; }; class C: public virtual A{ public: virtual void foo(){}; }; class D: B, C{}; The last line yields a compilation error citing ambiguity. As I understand it, the pr...
I would like to achieve this in C# (Pseudocode) class A; class B : A; class C : A, B; ... A ac = (A)c; ... B bc = (B)c; Is this possible? ...
Here's an example using multiple interface inheritance in Java and there's an issue. Note that I fully know why there's an issue and this is not the point of my question. The question is about how you name this particular multiple interface inheritance ambiguity, if there's a name for it. For example, in C++, the ambiguity that arises...
Consider a sports club situation. A club can have a Club manager and 1 or more Coaches (1 coach per team) So, here is an example of the Manager and Coach classes. Class ClubManager { public void RegisterMember() { // code for registering a member.. } } Class Coach { public void DeviceTeamFormation() { ...
Can anyone explain me why c# not supporting multiple inheritance since c++ supporting multiple inheritance ? how it is possible ? How c++ supports ? ...
We all know why Java does/should not have multiple inheritance. So this is not questioning about what has already been debated till-cows-come-home. This discusses what we would do when we wish to create a class that has the characteristics of two or more other classes. Probably, most of us would do this to "inherit" from three classes....
If I had: class A(object): varA = 1 inst = A() Then how would I retrieve the keys of all variables on inst? I'd want something like ["varA"] So far, I've gotten this: vars(inst.__class__).keys() #returns ['__dict__', '__weakref__', '__module__', 'varA', '__doc__'] I'm fine with that, I'd just ignore the double-under vars. My ...
I'm writing a program where each component has an inheritance structure has three levels... ui, logic, and data... where each of these levels has an interface of defined functionality that all components must implement. Each of these levels also has some functionality that could be written generically for the whole interface, rather tha...
(I’m sorry if this has been asked before; the search feature seems to be broken: the results area is completely blank, even though it says there are a few pages of results… in Chrome, FireFox, and Safari) So, I’m just learning C++… and the book I’m moving through is doing a really bad job of explaining constructors in a way that I can g...