Make zipWithIndex return a `View[(A, Int)]`

[julienrf]

Make zipWithIndex return a `View[(A, Int)]`

[odersky]

I don't think this is a good idea. If you have both strict and lazy collections, it's very important to have a clear picture what returns what. Ideally, only .view returns a lazy collection. We currently violate that principle with mapValues and some other map-related functions. That's not good, people get confused. Maybe there's no way around mapValues. But we should not make the problem bigger.

[julienrf]

OK, so users would just write .view.zipWithIndex

[odersky]

Yes, exactly.

[szeiger]

I agree. I did this as a micro-optimization in https://github.com/slick/slick/blob/master/slick/src/main/scala/slick/util/ConstArray.scala because it's the only kind of zipWithIndex we needed (which is probably true in general for immutable collections) but for a general-purpose library I don't think it's worth the inconsistency. Plus, a copying zipWithIndex could be useful for mutable collections.