[Python-ideas] Yielding from the command line

[Martin Teichmann]

Hi List,

I'm currently trying to convince my company that asyncio is a great
thing. After a lot of critique, the newest thing is, people complain:
I cannot test my code on the command line! And indeed they are
right, a simple

   a = yield from some_coroutine()

is not possible on the command line, and doesn't make sense.

Wait a minute, really?

Well, it could make sense, in an asyncio-based command line.
I am thinking about a python interpreter whose internal loop is
something like

    @coroutine
    def commandline():
        while True:
            cmd = yield from input_async()
            code = compile(cmd, "<stdin>", "generator")
            yield from exec(code)

A new compile mode would allow to directly, always create a
generator, and exec should be certainly be able to handle this.

I think this would not only make people happy that want to test
code on the command line, but also all those people developing
command line-GUI combinations (IPython comes to mind),
which have to keep several event loops in sync.

Greetings

Martin