Dart doesn’t inherit static methods to derived classes. So it makes no sense to create abstract static methods (without implementation). If you want a static method in class Main you have to fully define it there and always call it like Main.name == EDIT == I’m sure I read or heard some arguments from Gilad … Read more
It’s not possible to install Foreign Keys to abstract models in Django. You can however install Foreign Keys to a non abstract base class. The only limitation is that the reverse Foreign Key relation will return the base class instances. You can circumvent this limitation by using django-polymorphic. Django Polymorphic allows you to query the … Read more
Just stumbled across this feature myself: You can just inherit from your abstract model in tests.py and test that as usual. When you run ‘manage.py tests’, Django not only creates a test database, but also validates & syncs your test models. Tested it with current Django trunk (version 1.2).
You can’t directly instantiate an abstract class, but you can create an anonymous class when there is no concrete class: public class AbstractTest { public static void main(final String… args) { final Printer p = new Printer() { void printSomethingOther() { System.out.println(“other”); } @Override public void print() { super.print(); System.out.println(“world”); printSomethingOther(); // works fine } … Read more
Update for Angular 10+ As of Angular 10, when using the IVY compiler, components that are inherited, and which contain Angular functionality, must be decorated with an empty @Directive() decorator. Read more about it here There’s no need to add @Component() annotations to abstract classes or register them to any module. It could be that … Read more
I haven’t seen the content at urban potato (its down) but Me and Smelch came up with a solution. Form itself inherits from an abstract class, so what they dont tell you is that its only the 1st level of inheritance that can’t be abstract, the 2nd on down can. From there its simply a … Read more
Use the abc module to create abstract classes. Use the abstractmethod decorator to declare a method abstract, and declare a class abstract using one of three ways, depending upon your Python version. In Python 3.4 and above, you can inherit from ABC. In earlier versions of Python, you need to specify your class’s metaclass as … Read more
You can’t. The place to do this is with Attributes. Eg [Name(“FooClass”)] class Foo { }
I don’t see anything wrong with this approach. You might have some basic type that can be described in concrete terms. Now, just because an object of this type might be further classified according to some subtype, it does not follow that all such subtypes are just as concrete; they may in turn require further … Read more