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Comment by _getify | Hacker News Reader

Huge fan of this article. Makes some really great points! Wish I could share and vote it up a thousand times. :)

I have been writing about exactly this topic, of why classes don't make sense (specifically for JS), in my second title of the "You Don't Know JS" book series, "this & Object Prototypes".

In particular, Chapter 6 makes the case for an alternate pattern to class-orientation design, which I call OLOO (objects-linked-to-other-objects) style code. OLOO implements the "behavior delegation" design pattern, and embraces simply peer objects linked together, instead of the awkwardness of parent-child abstract class semantics.

https://github.com/getify/You-Dont-Know-JS/blob/master/this%...

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Kyle, the figures (fig4.png, fig5.png) are missing from that page. Other pages too. I'm one of your kickstarter contributors, but I was unable to read & review some of the chapters because significant parts of the text refer to missing diagrams.

They're coming. It's an artifact of working with a book publisher and the art department and all that. Sorry for the confusion.

A rough, hand drawn sketch scanned to gif or png until the official artwork is ready would be 100x better than a broken link.

OK, draft figures posted now.

https://github.com/getify/You-Dont-Know-JS/tree/master/this%...

"objects-linked-to-other-objects" - why not use the established "composition over inheritance": http://en.wikipedia.org/wiki/Composition_over_inheritance

Or does it mean something else?

OLOO is quite different from both inheritance and composition. It embraces delegation rather than covering it up or running away from it. :)

Can you give an actual example of the difference between composition and delegation? In my definition those two are just two different perspectives on the same thing.

A super quick, simple illustration of the difference, which comes down to the fact that delegation is differential, whereas composition is complete:

https://gist.github.com/getify/9895188

For a bit more "real world" of a scenario, you can also compare the `LoginController` / `AuthController` mechanism here, first shown with inheritance+composition, and then shown with simpler OLOO-style delegation:

https://github.com/getify/You-Dont-Know-JS/blob/master/this%...

Ah, thanks. That clarifies things. Neat!

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