asyncgui 0.6.1

A thin layer that helps to build async/await-based APIs using callback-based APIs

AsyncGui

A thin layer that helps to wrap a callback-style API in an async/await-style API.

How to use

Despite its name, the application of asyncgui is not limited to gui programs. You can wrap any kind of callback-based APIs in it. The simplest example of it would be sched, whose the whole feature is timer. All you need is just few lines of code:

import sched
import asyncgui

s = sched.scheduler()

# Wrapping 'scheduler.enter()'
async def sleep(duration, *, priority=10):
    sig = asyncgui.ISignal()
    event = s.enter(duration, priority, sig.set)
    try:
        await sig.wait()
    except asyncgui.Cancelled:
        s.cancel(event)
        raise


async def main():
    print('A')
    await sleep(1)  # Now you can sleep in an async-manner
    print('B')
    await sleep(1)
    print('C')


asyncgui.start(main())
s.run()

And you already have structured concurrency APIs as well:

async def print_numbers():
    for i in range(10):
        await sleep(.1)
        print(i)


async def print_letters():
    for c in "ABCDE":
        await sleep(.1)
        print(c)


async def main():
    # Let print_letters() and print_numbers() race.
    # As soon as any of them finishes, the other one gets cancelled.
    tasks = await asyncgui.wait_any(print_letters(), print_numbers())
    if tasks[0].finished:
        print("print_letters() won")
    else:
        print("print_numbers() won")
    print('main end')

A
0
B
1
C
2
D
3
E
print_letters() won
main end

Installation

It's recommended to pin the minor version, because if it changed, it means some important breaking changes occurred.

poetry add asyncgui@~0.6
pip install "asyncgui>=0.6,<0.7"

Tested on

• CPython 3.8
• CPython 3.9
• CPython 3.10
• CPython 3.11
• CPython 3.12 (3.12.1 or later)

Async-libraries who relies on this

• asyncsched
• asynckivy
• asynctkinter
• asyncpygame