Software Engineering Stack Exchange
Software Engineering Stack Exchange

Questions tagged [inheritance]

Inheritance is a way to reuse code of existing objects, or to establish a subtype from an existing object, or both, depending upon programming language support.

Inheritance is a way to reuse code of existing objects, or to establish a subtype from an existing object, or both, depending upon programming language support.

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Where does this concept of "favor composition over inheritance" come from?

In the last few months, the mantra "favor composition over inheritance" seems to have sprung up out of nowhere and become almost some sort of meme within the programming community. And every time I see it, I'm a little bit mystified. It's like…
Mason Wheeler
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Is there any "real" reason multiple inheritance is hated?

I've always liked the idea of having multiple inheritance supported in a language. Most often though it's intentionally forgone, and the supposed "replacement" is interfaces. Interfaces simply do not cover all the same ground multiple inheritance…
Panzercrisis
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Why should I prefer composition over inheritance?

I always read that composition is to be preferred over inheritance. A blog post on unlike kinds, for example, advocates using composition over inheritance, but I can't see how polymorphism is achieved. But I have a feeling that when people say…
MustafaM
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Why would Square inheriting from Rectangle be problematic if we override the SetWidth and SetHeight methods?

If a Square is a type of Rectangle, than why can't a Square inherit from a Rectangle? Or why is it a bad design? I have heard people say: If you made Square derive from Rectangle, then a Square should be usable anywhere you expect a…
user793468
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When to use abstract classes instead of interfaces with extension methods in C#?

"Abstract class" and "interface" are similar concepts, with interface being the more abstract of the two. One differentiating factor is that abstract classes provide method implementations for derived classes when needed. In C#, however, this…
Gulshan
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How are mixins or traits better than plain multiple inheritance?

C++ has plain multiple inheritance, many language designs forbid it as dangerous. But some languages like Ruby and PHP use strange syntax to do the same thing and call it mixins or traits. I heard many times that mixins/traits are harder to abuse…
Gherman
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Why is it good to split a program into multiple classes?

I'm still a student in high school (entering 10th grade), and I have yet to take an actual computer course in school. Everything I've done so far is through books. Those books have taught me concepts such as inheritance, but how does splitting a…
kullalok
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LSP vs OCP / Liskov Substitution VS Open Close

I am trying to understand the SOLID principles of OOP and I've come to the conclusion that LSP and OCP have some similarities (if not to say more). the open/closed principle states "software entities (classes, modules, functions, etc.) should be…
Kolyunya
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Code Smell: Inheritance Abuse

It's been generally accepted in the OO community that one should "favor composition over inheritance". On the other hand, inheritance does provide both polymorphism and a straightforward, terse way of delegating everything to a base class unless…
dsimcha
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What is a type system?

Background I am designing a language, as a side project. I have a working assembler, static analyser, and virtual machine for it. Since I can already compile and run non-trivial programs using the infrastructure I've built I thought about giving a…
Mael
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Is OO-programming really as important as hiring companies place it?

I am just finishing my masters degree (in computing) and applying for jobs. I've noticed many companies specifically ask for an understanding of object orientation. Popular interview questions are about inheritance, polymorphism, accessors etc. Is…
ale
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Are Python mixins an anti-pattern?

I'm fully aware that pylint and other static analysis tools are not all-knowing, and sometimes their advice must be disobeyed. (This applies for various classes of messages, not just conventions.) If I have classes like class related_methods(): …
cat
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Why is inheritance bad in a Person-Student model?

I've just started learning about Inheritance vs Composition and it's kind of tricky for me to get my head around it for some reason. I have these classes: Person class Person { public string Name { get; set; } public int Age { get; set; } …
Octavian Niculescu
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Why inherit a class without adding properties?

I found an inheritance tree in our (rather large) code base that goes something like this: public class NamedEntity { public int Id { get; set; } public string Name { get; set; } } public class OrderDateInfo : NamedEntity { } From what I…
robotron
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Why is inheritance generally viewed as a bad thing by OOP proponents

I keep hearing the phrase "Favour Composition over Inheritance" from GoF, which is being annoyingly mentioned repeatedly by my friend, who thinks it is a valid blanket statement. But is it not more sensible to consider that the real reason why…
RonaldMunodawafa
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