Set length property

Brendan Eich brendan at
Tue Feb 14 19:08:23 PST 2012

Tab Atkins Jr. wrote:
>> IME they're ducktyped by the presence of forEach (this is far from perfect).
>> >  Length has nothing to do with iterability. What about generators?
> I don't want to go looking anything up right now, but I have lots of
> memories of things looking for the presence of "length" to denote an
> array-like.

Array-like != iterable.

Eager length is a problem for lazy lists (iterators).


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