One of the best ways would be using the enum polymorphism technique: public class EnumTest { public enum Foo { A { @Override public Bar getBar() { return Bar.Alpha; } }, B { @Override public Bar getBar() { return Bar.Delta; } }, C { @Override public Bar getBar() { return Bar.Alpha; } }, ; public … Read more
A reference cycle simply means one or more objects referencing each other, such that if you drew it out on paper with arrows representing the dependencies you would see a cycle. The (almost) simplest reference cycle is having two objects a and b that refer to each other: a.other = b b.some_attr = a Naive … Read more
If you do import foo (inside bar.py) and import bar (inside foo.py), it will work fine. By the time anything actually runs, both modules will be fully loaded and will have references to each other. The problem is when instead you do from foo import abc (inside bar.py) and from bar import xyz (inside foo.py). … Read more
Let me repeat your question: “My question, how cyclic data structures makes reference count above zero, kindly request to show with example in C++ program. How the problem is solved by weak_ptrs again with example please.” The problem occurs with C++ code like this (conceptually): class A { shared_ptr<B> b; … }; class B { … Read more
If you do import foo (inside bar.py) and import bar (inside foo.py), it will work fine. By the time anything actually runs, both modules will be fully loaded and will have references to each other. The problem is when instead you do from foo import abc (inside bar.py) and from bar import xyz (inside foo.py). … Read more