Async REPL support

[nickovs]

Now that the asyncio support in Micropython is getting more mature and stable[^1], it would be valuable to have an async-compatible REPL. By this I mean two things:

• The ability to type await foo() at the REPL and have it properly await the return of an asynchronous function
• The ability for asynchronous tasks to continue to run in the background while waiting for the user to type something at the REPL.

A great deal of what people do with Micropython involves somewhat real time interaction and multiple activities going on at once. Interrupt handlers are fine for some of this but now that we have good async support it's getting easier to write more readable code. Being able to interactively write, use and debug that code would be an asset to the community.

I'd be interested to hear if anyone else thinks that this would be valuable.

[^1] @peterhinch has an excelent tutorial on this.

[andrewleech]

aiorepl has been officially supported for some years now, see https://github.com/micropython/micropython-lib/blob/master/micropython%2Faiorepl%2Faiorepl.py

mip install aiorepl

[nickovs]

Aha! Thank you. I guess it was a good idea, it just wasn't original!