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249 points mattcollins | 1 comments | | HN request time: 0s | source
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gigatexal ◴[] No.42190772[source]
I’m gonna buy the book but I prefer composition over OOP. I prefer to have an init that takes some params where those params are fully baked clients of whatever services I need and then the class just uses them as needed. I don’t see a lot of value in having a Python class that might have a few or more classes that it extends where all the functions from all the classes crowd up the classes namespace.

Class Foo.__init__(self, db, blob_storage, secrets_manager, …)

Instead of class Foo(DB, BlobStorer, SecretsMgr)

Etc

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yxhuvud ◴[] No.42190800[source]
Why on earth do you put composition and OOP as opposing techniques? Composition is just one more technique in the OOP toolbox and there is nothing in OOP that mandates an inheritance based architecture.
replies(1): >>42191144 #
crabmusket ◴[] No.42191144[source]
Mainstream OOP languages (looking at you Java) have failed to make composition as convenient as inheritance.
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yxhuvud ◴[] No.42192325[source]
How is composition inconvenient?
replies(1): >>42197858 #
1. mdaniel ◴[] No.42197858[source]
Contrast the Java way

    class Delegated implements Base {
        final Base b;
        public Delegated(Base b) { this.b = b; }
        @Override
        public void printMessage() { b.printMessage(x); }
        @Override
        public void printMessageLine() { b.printMessageLine(x); }
with the Kotlin way https://kotlinlang.org/docs/delegation.html#overriding-a-mem...

OT1H, yes, sane people using IJ would just alt-Insert, choose delegate to, and move on with life. But those misguided folks using VS Code, vim, or a magnetized needle and a steady hand would for sure find delegating to a broader interface to be a huge PITA