falcon.async_to_sync() does not work inside an async loop

[vytas7]

The easiest way to reproduce is running the Python REPL in async mode:

python -m asyncio

>>> import asyncio
>>> import falcon
>>> async def noop(): ...
... 
>>> falcon.async_to_sync(noop)
Traceback (most recent call last):
  <...>
RuntimeError: Runner.run() cannot be called from a running event loop

[vytas7]

Note that it is not a very high priority issue to fix since the primary use case of falcon.async_to_sync() is running it from synchronous code outside of any loop.

But if there is an elegant solution, it would be nice to fix it. I know SQLAlchemy uses Greenlet to achieve this.

[CaselIT]

Personally I think there should just be a mention of it in the function docs