Fix RecursionError when iterating streams

[eric-wieser]

next(self) was previously just a recursive call that does nothing.

This now implements __next__ using the actual implementation, and lets the python2-compatibility next() just wrap it.

[Byron]

Thanks a lot, I have a feeling that this issue was present for a long time already!

Do you think Python 2 compatibility is still required? Support for it was dropped a while ago and if you agree it can be dropped entirely.

[eric-wieser]

I have no objection to dropping the next method entirely; I left it only for the sake of being conservative.

[eric-wieser]

Feel free to commit through the github UI if you want to drop this Python2 compatibility layer entirely:

Suggested change

next = __next__

Note that there may be some downstream code that relies on using next because __next__ was broken though!

[Byron]

Ah, right. Oh well, let's be conservative then.

[Byron]

Great! Let's do that and the PR can be merged. Thank you