async enumeration - possible?

[Frank Millman]

Hi all

Python 3.6 has introduced Asynchronous Generators, which work very well.

Python 3.6.0b4 (default, Nov 22 2016, 05:30:12) [MSC v.1900 64 bit (AMD64)] 
on win32
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>>> import asyncio
>>> loop = asyncio.get_event_loop()
>>>
>>> async def counter(n):
...   for i in range(n):
...     yield i
...
>>> async def main():
...   c = counter(5)
...   async for j in c:
...     print(j)
...   print('done')
...
>>> loop.run_until_complete(main())
0
1
2
3
4
done

However, it does not allow you to enumerate over the generator output -

>>> async def main():
...   c = counter(5)
...   async for j, k in enumerate(c):
...     print(j, k)
...   print('done')
...
>>> loop.run_until_complete(main())
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File 
"C:\Users\User\AppData\Local\Programs\Python\Python36\lib\asyncio\base_events.py", 
line 466, in run_until_complete
    return future.result()
TypeError: 'async_generator' object is not iterable
>>>

Is there any technical reason for this, or is it just that no-one has got 
around to writing an asynchronous version yet?

Frank Millman