Composition over Inheritance

https://medium.com/humans-create-software/composition-over-inheritance-cb6f88070205

• Gorilla/Banana problem — you request a banana, but you end up with a gorilla holding the banana and the entire jungle with it.
• inheritance is when you design your types around what they are, and composition is when you design types around what they do.
• the really big problem with inheritance is that you’re encouraged to predict the future.

對了，以 php 來說，透過 constructor 進行 DI 注入多個類別比較好？

還是直接用 trait 輕鬆尻一尻比較好？