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Questions tagged [subclass]

A subclass is a class that derives or inherits from a parent (or super) class. Subclassing is used extensively in object-oriented programming (OOP).

A subclass is any class that inherits from a parent (or super/base) class. Depending on the language, a subclass will have a subset of the attributes and methods of the (parent/base) class from which it inherits. As a result, it is important to always tag a question with the language being used when tagging it with this tag

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How do I check if a type is a subtype OR the type of an object?

To check if a type is a subclass of another type in C#, it's easy: typeof (SubClass).IsSubclassOf(typeof (BaseClass)); // returns true However, this will fail: typeof (BaseClass).IsSubclassOf(typeof (BaseClass)); // returns false Is there any way…
Daniel T.
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How to find all the subclasses of a class given its name?

I need a working approach of getting all classes that are inherited from a base class in Python.
Roman Prykhodchenko
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How do I check (at runtime) if one class is a subclass of another?

Let's say that I have a class Suit and four subclasses of suit: Heart, Spade, Diamond, Club. class Suit: ... class Heart(Suit): ... class Spade(Suit): ... class Diamond(Suit): ... class Club(Suit): ... I have a method which receives…
snakile
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How do you find all subclasses of a given class in Java?

How does one go about and try to find all subclasses of a given class (or all implementors of a given interface) in Java? As of now, I have a method to do this, but I find it quite inefficient (to say the least). The method is: Get a list of all…
Avrom
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Test whether a Ruby class is a subclass of another class

I would like to test whether a class inherits from another class, but there doesn't seem to exist a method for that. class A end class B < A end B.is_a? A => false B.superclass == A => true (N.B. the is_a? test above does not make any sense, as…
Confusion
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Subclass in type hinting

I want to allow type hinting using Python 3 to accept sub classes of a certain class. E.g.: class A: pass class B(A): pass class C(A): pass def process_any_subclass_type_of_A(cls: A): if cls == B: # do something elif…
user1211030
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How do you use the ellipsis slicing syntax in Python?

This came up in Hidden features of Python, but I can't see good documentation or examples that explain how the feature works.
miracle2k
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Why aren't superclass __init__ methods automatically invoked?

Why did the Python designers decide that subclasses' __init__() methods don't automatically call the __init__() methods of their superclasses, as in some other languages? Is the Pythonic and recommended idiom really like the following? class…
jrdioko
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Abstract classes in Swift Language

Is there a way to create an abstract class in the Swift Language, or is this a limitation just like Objective-C? I'd like to create a abstract class comparable to what Java defines as an abstract class.
kev
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How to test if one java class extends another at runtime?

How to I test if a is a subclass of b? Class a = A.class; Class b = B.class;
Armand
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Understanding __init_subclass__

I finally upgraded my python version and I was discovering the new features added. Among other things, I was scratching my head around the new __init_subclass__ method. From the docs: This method is called whenever the containing class is…
EsotericVoid
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How do I check if an object's type is a particular subclass in C++?

I was thinking along the lines of using typeid() but I don't know how to ask if that type is a subclass of another class (which, by the way, is abstract)
Chad
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When do you need to explicitly call a superclass constructor?

So say I have a subclass that extends a superclass. In what scenarios do I need to explicitly type super() to get the superclass constructor to run? I'm looking at an example in a book about abstract classes and when they extend it with a…
jhlu87
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Getting the name of a sub-class from within a super-class

Let's say I have a base class named Entity. In that class, I have a static method to retrieve the class name: class Entity { public static String getClass() { return Entity.class.getClass(); } } Now I have another class extend…
Matt Huggins
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How does inheritance of __slots__ in subclasses actually work?

In the Python data model reference section on slots there is a list of notes on using __slots__. I am thoroughly confused by the 1st and 6th items, because they seem to be contradicting each other. First item: When inheriting from a class…
jathanism
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