this post was submitted on 03 Jul 2023
100 points (96.3% liked)
Programming
17319 readers
89 users here now
Welcome to the main community in programming.dev! Feel free to post anything relating to programming here!
Cross posting is strongly encouraged in the instance. If you feel your post or another person's post makes sense in another community cross post into it.
Hope you enjoy the instance!
Rules
Rules
- Follow the programming.dev instance rules
- Keep content related to programming in some way
- If you're posting long videos try to add in some form of tldr for those who don't want to watch videos
Wormhole
Follow the wormhole through a path of communities !webdev@programming.dev
founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
You're not describing composition.
Go Files do not "hasa reader". You don't do file.reader.read(), you just do file.read(), that's inheritance as file has inherited the read() method.
You're confusing polymorphism for inheritance.
read
is a method on an interface thatFile
implements - it is not inherited from a base class. You can use thatFile
directly, or wherever aReader
interface (or whatever the name is, idk I don't really do Go) is expected.Composition do not necessitate the creation of a new field like x.reader or x.writer, what are you on?
https://www.infoworld.com/article/3409071/java-challenger-7-debugging-java-inheritance.html#toc-2
composition is literally the "has a" relationship. That's how its always been taught.
Man, I honestly have no idea why they are downvoting you. Composition literally means taking common behavior and placing it in external objects behind interfaces using a has-a relationship.
No idea why they are denying this. Inheritance vs composition is the same as "is-a" vs "has-a". In composition re usability isn't done via inheritance but code encapsulation.
Saying that in Go objects can implement many interfaces is the Interface Segregation principle from SOLID. Basically having small interfaces instead of a big interface with methods that may not be implemented by all implementors.