multiple-inheritance

问题 I'm trying to see how I can structure a script in a way that I can use the inheritance method. I'm fairly new to python. And my problem is using variables in one class from another class-def. I just recently learned about the super function and I don't think I'm using it right because it keeps printing and recalculating everything that it's pulling from. Let's say I have a bunch of messages coming in a text file delimited by commas that give me different information. I want to be able to take

问题 I'm building a fairly large plugin-driven app in my spare time, and have come across a show stopping design flaw. My app uses policy/traits based design, but because I use Qt it is done just through MI (rather than templates and MI). Some of these classes are pure virtual and some perform rather critical functions under the hood that the end-user should never touch. My problem is that some of these classes require signals/slots and therefore derive from QObject, no problem I can just

问题 This question already has answers here : Multiple inheritance with one base class (2 answers) Closed 3 years ago . I'm implemeting this diamond inheritance: class Object { private: int id; string name; public: Object(){}; Object(int i, string n){name = n; id = i;}; }; class Button: virtual public Object { private: string type1; int x_coord, y_coord; public: Button():Object(){}; Button(int i, string n, string ty, int x, int y):Object(i, n){ type = ty; x_coord = x; y_coord = y;}; }; class

问题 I was going through the diamond problem and thought will work on various scenarios. And this is one among them which I was working on. #include <iostream> using namespace std; class MainBase{ public: int mainbase; MainBase(int i):mainbase(i){} void geta() { cout<<"mainbase"<<mainbase<<endl; } }; class Derived1: public MainBase{ public: int derived1; int mainbase; Derived1(int i):MainBase(i),derived1(i) {mainbase = 1;} public: void getderived1() { cout<<"derived1"<<derived1<<endl; } }; class

问题 This isn't an actual programming question, I just need advice on how to structure a part of my program. The program is divided into a client and a server part. Both share certain code, including base classes. Here's a representation of the code I'm having trouble with: Shared classes: class BaseEntity { public: virtual void EmitSound(std::string snd) {} virtual bool IsPlayer() {return false;} }; class BasePlayer : public BaseEntity { public: bool IsPlayer() {return true;} } Serverside classes

问题 I have already looked upon the the usage of interface, abstract classes and inheritance. I see that each have their uses but, I am still kind of confused. I know that generally a class can extend only another class, although some may support multiple inheritance, but it can implement more than one interface (which is probably the main reason for using an interface). However this class can also be extended by another class If I am correct. I have also seen that abstract classes may be faster

问题 I am experimenting with ways to implement a simplified Term Rewriting System (TRS)/Symbolic Algebra System in Python. For this I would really like to be able to be able to intercept and modify the operands in particular cases during the class instance instantiation process. The solution I came up with, was to create a metaclass that modifies the typical call behavior of a class object (of type 'type'). class Preprocess(type): """ Operation argument preprocessing Metaclass. Classes using this

问题 I have a Maven project multimodule project. Some of the modules create custom packaging for the libraries produced by the other modules. The packaging being used has its own suite of versioned dependencies that I need to play nice with. As an example: my parent POM might have an entry for e.g. commons-codec:commons-codec 1.4 , my "core-lib" POM includes it as a dependency (sans explicit version), and I want to make sure my packaging module bundles in the right version. However, the specific

问题 According to Douglas Crockford I could use something like http://javascript.crockford.com/prototypal.html (with a little bit of tweaking)... but I am interested in jQuery way of doing it. Is it good practice using $.extend ? I have 4 classes : var A = function(){ } A.prototype = { name : "A", cl : function(){ alert(this.name); } } var D = function(){} D.prototype = { say : function(){ alert("D"); } } var B = function(){} //inherits from A B.prototype = $.extend(new A(), { name : "B" }); var C

问题 In the following example: class A { public: virtual void f() { cout << "a" << endl; } virtual void h() { cout << "A" << endl; } }; class s1 : public A { public: virtual void f() { cout << "s1" << endl; } }; class s2 : public A { public: virtual void h() { cout << "s2" << endl; } }; class GS : public s1, public s2 { public: }; int main() { s1 *q = new GS; q->h();//no problem GS a; a.h();//error } Why does a.h(); give an ambiguity error yet q->h(); doesn't? Doesn't *q have an instance of GS