If not for-in then what?

Axel Rauschmayer axel at rauschma.de
Wed Mar 28 08:11:24 PDT 2012


On Mar 28, 2012, at 17:06 , John J Barton wrote:

> In another thread Allen says:
> 
>    we infer from array behavior that for-in was intended to iterate over the data elements of an object and not the behavioral elements (eg methods).
> 
> Similar comments have been implied around the discussion of enumerable properties. I personally have never seen any JS code that had this assumption. On the contrary, before Object.keys(), for-in was widely used as a half-baked meta-programming iterator.
> 
> If for-in is not intended to iterate all properties of an object then what is?

Object.getOwnPropertyNames() together with a hand-written traversal of the prototype chain.

-- 
Dr. Axel Rauschmayer
axel at rauschma.de

home: rauschma.de
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