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Hi all,

Regarding the behaviour of the "async with" statement: it seems that the description of it in PEP492, and the language documentation, do not match the behaviour of CPython (v3.6.1).

The PEP and the docs here:
https://www.python.org/dev/peps/pep-0492/#asynchronous-context-managers-and-async-with
https://docs.python.org/3/reference/compound\_stmts.html#async-with

say that "async with" is equivalent to a particular use of try/except/else.

But the implementation seems more like a try/except/finally, because the \_\_aexit\_\_ is always executed, even if a return statement is in the try block ("else" won't be executed if there's a "return" in the "try"). Also, as per normal "with", the implementation is a bit more complex than try/except/finally because you don't want to execute the \_\_aexit\_\_ method twice if there is an exception in the try.

Can someone please clarify the exact behaviour of "async with"?

Background: in implementing "async with" in MicroPython, we went by the PEP/docs, and now our behaviour doesn't match that of CPython.

Cheers,

Damien.