Why can’t for-of be applied to iterators?

Andy Wingo wingo at igalia.com
Mon Jun 10 00:32:54 PDT 2013


On Sun 09 Jun 2013 11:34, Jason Orendorff <jason.orendorff at gmail.com> writes:

> I think it's a mistake for iterators not to be iterable.

I agree, FWIW.

I think I would go farther and suggest that _only_ iterators be
iterable.  That way, the RHS of a for-of is expected to be an iterator.
In the worst case you end up having:

  var a = [1, 2, 3, 4]
  for (let x of values(a))
    ...

instead of 

  for (let x of a)
    ...

which to my eye is better anyway.  Making an "itertools"-like library
difficult is a definite drawback of the current spec.

Andy


More information about the es-discuss mailing list