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0
votes
0
answers
59
views
Casting collection<implementation> to collection<interface> [duplicate]
In Java, having two interfaces:
public interface SomeAbstractResult {}
public interface SomeInterface {
Collection<SomeAbstractResult> someMethod();
SomeAbstractResult someMethod2();
}
...
0
votes
1
answer
86
views
Constructor not accepting list of derived class as argument [duplicate]
I have tried using both base class and interface and in both instances I am told a constructor that takes my arguments does not exist. I have two classes that are related to each other and I want to ...
-3
votes
0
answers
27
views
Why is explicit Parent.__init__(self) discouraged in Python Multiple Inheritance compared to super()? [duplicate]
Body: I am learning Multiple Inheritance in Python. In my code, I am initializing the parent classes by calling them explicitly by name, like this:
I read that I should use super(), but when I use ...
Best practices
0
votes
6
replies
172
views
dynamic_cast to any one of several options
Somewhat similar to this question, I have something like this:
class DerivedA: public Base
{
void operation(const Base& x, const Base& y) override // pure virtual in Base
{
...
0
votes
0
answers
51
views
Mapstruct and multiple derived classes
I am having trouble wrapping my head around subclass mappings. I have 3 classes:
@Data
public class Parent {
long id;
String name;
public boolean isEmpty() {
return StringUtils.isEmpty(name)...
Advice
0
votes
9
replies
127
views
Why the inherited method output parent's data?
Explain please why the output is "Base" ? Isn't getClassName method inherited?
class Base {
public String className = "Base";
public String getClassName() {
...
3
votes
1
answer
198
views
"The type initializer threw an exception" even though static fields are initialized [duplicate]
I'm getting a TypeInitializationException when running this C# code.
It happens when a constructor tries to add an instance to a static list that should already be initialized.
You can run it here:
...
0
votes
1
answer
128
views
C# .NET extension without extension method [closed]
I have a base class and multiple derived classes:
public class Camera
{
}
public class CameraManufacturerA : Camera
{
}
public class CameraManufacturerB : Camera
{
}
public class ...
Best practices
1
vote
6
replies
226
views
Base class and derived classes in Qt
I'm building a Qt wrapper for RtMidi. As starting point I created two separate classes QMidiOut and QMidiIn that wrap RtMidiOut and RtMidiIn.
I don't want to duplicate code for the common methods (e.g....
2
votes
0
answers
64
views
SWIG multiple inheritance problem when returning a C++ class wrapped as an interface
I'm trying to wrap a C++ class using SWIG that involves multiple inheritance and another class with a method returning a shared pointer to a class declared as an interface in SWIG. Here is a ...
1
vote
1
answer
81
views
Problem with manim rendering of the arrows
I want to use manim to render a spiral, which is crucial for later animation. Even the output says that the first arrow's module is greater than the second arrow, the render result says that the first ...
1
vote
3
answers
94
views
Inheritance of decorated classes
I'm using Python decorators to implement common functionality across multiple classes. The problem comes when I want the decorated classes to inherit from each other: super() doesn't seem to delegate ...
2
votes
0
answers
122
views
Hibernate 6 native query on parent class fails with "ORA-17006: Invalid column name"
After upgrading from Hibernate 5 to Hibernate 6, a native query that used to work now fails with an "ORA-17006: Invalid column name" error.
Entity definitions
Base class:
@Entity
@Table(name = "...
2
votes
2
answers
197
views
derived class cannot call recursively inherited member functions C++
I'm making it using multi inheritance with a pair struct that contains
an index and the type of the element in a recursive structure like this:
template<int index, typename... ts>
struct ok;
...
1
vote
1
answer
61
views
How to define a generic type with `new(...args)` in TypeScript?
In TypeScript, it is possible to define a type of a constructable class using new(...args: any):
// We have some class inheritance
abstract class Something {}
class ChildOfSomething extends Something {...