Minimalist (why) classes ?

Rick Waldron waldron.rick at
Sun Nov 13 07:54:15 PST 2011

A few more thoughts...

On Nov 13, 2011, at 5:08 AM, Jake Verbaten <raynos2 at> wrote:

> Neither of them are fit for standardization. Selfish and Prototype are both incapable of correctly "deep copying" arrays or objects,
> Why does it matter that they don't deep copy? Deep copying is a difficult problem that needs to be standardized separately. I've personally avoided deep copying for this reason and don't use it anymore.
> One can accept that an extend is merely a shallow copy properties by reference, because this (although limited) behavior is easy to understand. 

Shallow copy is only good for one level of property lists whose assignment expressions are all primitive, anything that is a reference is going to allow the destination to mutate the source, this is wrong. 

> I have a version of Object.extend that is a "shallow own merge".
> However having a deep copy mechanism that works without obscure edge-cases would be great.

Can you be specific? What obscure edge cases have you previously encountered?

> Of course it would be nice if we had the choice of deep vs shallow copy within the API.

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