Suggestions for Set

Erik Arvidsson erik.arvidsson at
Wed Oct 3 07:47:36 PDT 2012

On Wed, Oct 3, 2012 at 3:24 AM, Andreas Rossberg <rossberg at> wrote:
> On 3 October 2012 05:38, Brendan Eich <brendan at> wrote:
>> Which is more important, iterating over holes (preserved if possible), or
>> skipping them and therefore spreading array-likes but not iterables?
> I, for one, couldn't care less about holes. We shouldn't compromise
> any useful feature just for the sake of preserving some array hole
> craziness.

Filling in holes with undefined seems like the right thing to do.
People do not depend on holes.

Having Array.prototype. at iterator skip holes is bad because we don't
have the index so we don't know that anything was skipped.

To repeat myself; holes are not common and we should keep things
simple and having Array.prototype. at iterator iterate over array[0] to
array[length - 1] is the most expected result.


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