unasync

Fibers "allow blocking and non-blocking implementations to share the same API" That's an interesting contrast to Python where the need to use "value = await fn()" v.s. "value = fn()" depending on whether or not that function is awaitable causes all kinds of API design complexity, all the way up to the existence of tools like https://github.com/python-trio/unasync which can code-generate the non-async version of a library from the async version.

Async Python has proven faster in my uses for IO and non-CPU-related stuff. But I think Python, either as a community or within the language, needs to solve the anti-pattern of maintaining separate sync and async versions of a library. I'm thinking specifically of aioredis and redis-py, both of which I've worked on. Some people are looking at ways to solve this. I know urllib3, elasticsearch-py, and a few others use unasync (https://github.com/python-trio/unasync) to transform async code into sync code, leaving one codebase supporting both uses in different namespaces. This leaves you with some conditional logic (is_async_mode() -- https://github.com/python-trio/hip/blob/master/src/ahip/util...). I'm seriously considering this approach.

This is also a problem over in Python-land. One of the interesting approaches is automatically generating non-async code from async code by editing out the async annotations (at the source level). The Trio folks call this "bleaching" the code, in reference to the "What color is your function?" blog post https://journal.stuffwithstuff.com/2015/02/01/what-color-is-... complaining about how the common approach to async in JavaScript divides the world into "red" (async) and "blue" (sync) functions that interoperate poorly - you can bleach your code if it's the wrong color. https://github.com/urllib3/urllib3/issues/1323 is a discussion of this. "Solution: we maintain one copy of the code – the version with async/await annotations – and then a little script maintains the synchronous copy by automatically stripping them out again. It's not beaut