class-design

If you want to associate some constant value with a class, here are two ways to accomplish the same goal: class Foo { public: static const size_t Life = 42; }; class Bar { public: enum {Life = 42}; }; Syntactically and semantically they appear to be identical from the client's point of view: size_t fooLife = Foo::Life; size_t barLife = Bar::Life; Is there any reason other than just pure style concerns why one would be preferable to another? The enum hack used to be necessary because many compilers didn't support in-place initialization of the value. Since this is no longer an issue, go for the

Let's consider python (3.x) scripts: main.py: from test.team import team from test.user import user if __name__ == '__main__': u = user() t = team() u.setTeam(t) t.setLeader(u) test/user.py: from test.team import team class user: def setTeam(self, t): if issubclass(t, team.__class__): self.team = t test/team.py: from test.user import user class team: def setLeader(self, u): if issubclass(u, user.__class__): self.leader = u Now, of course, i've got circular import and splendid ImportError. So, not being pythonista, I have three questions. First of all: i. How can I make this thing work ? And,

If I create a class MyClass and it has some private member say MyOtherClass, is it better to make MyOtherClass a pointer or not? What does it mean also to have it as not a pointer in terms of where it is stored in memory? Will the object be created when the class is created? I noticed that the examples in QT usually declare class members as pointers when they are classes. Regards Mark If I create a class MyClass and it has some private member say MyOtherClass, is it better to make MyOtherClass a pointer or not? you should generally declare it as a value in your class. it will be local, there

public class Parent { .... } public class Child1 extends Parent { .... public void foo() { .... } } public class Child2 extends Parent { .... public void foo() { .... } } Here method foo() only exists in the Child classes and CAN NOT be added to the Parent class (not even abstract method). In this situation when I want to call the foo() method on obj which is Parent class's reference then I need to use intanceof with multiple if..else which I want to avoid. Parent obj = ...// Object of one of the child classes obj.foo(); EDIT: I Need to use type of obj as Parent only. Else I will not be able

I have been trying to figure out the best way to use bitmask or bitfields in PHP for a long time now for different areas of my application for different user settings and permissions. The farthest I have come so far is from a class contributed by svens in the Stack Overflow post Bitmask in PHP for settings? . I have slightly modified it below, changing it to use class constants instead of DEFINE and making sure the get method is passed an int only. I also have some sample code to test the class's functionality below. I am looking for any suggestions/code to improve this class even more so it

This question already has an answer here: In Java, are enum types inside a class static? 2 answers I have an interface - here's a nicely contrived version as an example: public interface Particle { enum Charge { POSITIVE, NEGATIVE } Charge getCharge(); double getMass(); etc... } Is there any difference in how implementations of this would behave if I defined the Charge enum as static - i.e. does this have any effect: public interface Particle { static enum Charge { POSITIVE, NEGATIVE } Charge getCharge(); double getMass(); etc... } No, it makes no difference. However the reason is not because

I'm working on a large project (for me) which will have many classes and will need to be extensible, but I'm not sure how to plan out my program and how the classes need to interact. I took an OOD course a few semesters back and learned a lot from it; like writing UML, and translating requirements documents into objects and classes. We learned sequence diagrams too but somehow I missed the lecture or something, they didn't really stick with me. With previous projects I've tried using methods I learned from the course but usually end up with code that as soon as I can say "yeah that looks