Alternatives to OOP in D

[Serg Gini]

On Monday, 1 September 2025 at 13:58:23 UTC, Brother Bill wrote:
> I have heard that there are better or at least alternative ways 
> to have encapsulation, polymorphism and inheritance outside of 
> OOP.
>
> With OOP in D, we have full support for Single Inheritance, 
> including for Design by Contract (excluding 'old').  D also 
> supports multiple Interfaces.
>
> What would be the alternatives and why would they be better?
> I assume the alternatives would have
> 1. Better performance
> 2. Simpler syntax
> 3. Easier to read, write and maintain
>
> If possible, please provide links to documentation or examples.

Usually alternative is related to composition.

https://en.wikipedia.org/wiki/Object_composition
https://en.wikipedia.org/wiki/Composition_over_inheritance