The idea on the OP can be fully implemented with ~10 lines of code in a
decorator -
which could be further factored out into a decorator-for-decorators:
```
import asyncio, inspect
def hybrid_decorator(func):
coro = inspect.iscoroutinefunction(func)
if coro:
async def inner(*args, **kw):
return await func(*args, **kw)
else:
def inner(*args, **kw):
return func(*args, **kw)
def wrapper(*args, **kw):
...
value = inner(*args, **kw)
...
return value
if coro:
wrapper = asyncio.coroutine(wrapper)
return wrapper
```
The thing is that just in Python 3.8 the `@courotine` decorator has been
deprecated -
not sure if there is another "in language" way of changing an already
defined,
no "await" in body, function to a coroutine function.
One way or another, this approach seems quite feasible for whoever wants
to make use of such a feature with no need for new syntax (but maybe need
for having an "undeprecated" way of doing what `@coroutine` does)
Here is the approach factored out to a "decorator decorator" that does the
dirty job:
```
def hybrid_async(deco):
@wraps(deco)
def wrapper(func):
coro = inspect.iscoroutinefunction(func)
if coro:
async def inner(*args, **kw):
return await func(*args, **kw)
else:
inner = func
wrapped = wraps(func)(deco(inner))
if coro:
wrapped = asyncio.coroutine(wrapped)
return wrapped
return wrapper
@hybrid_async
def log_run(func):
@wraps(func)
def wrapper(*args, **kw):
print("start", flush=True)
v = func(*args, **kw)
print("stop", flush=True)
return v
return wrapper
```
On Tue, 11 Feb 2020 at 11:59, Soni L. <fakedme...@gmail.com> wrote:
>
>
> On 2020-02-11 4:33 a.m., Ben Rudiak-Gould wrote:
> > On Mon, Feb 10, 2020 at 9:50 AM Andrew Barnert via Python-ideas
> > <python-ideas@python.org> wrote:
> > > It’s a well-known problem that async is “contagious”: [...]
> > >
> > > But C# and every other language that’s borrowed the idea has the same
> problem, and as far as I know, nobody’s thought of a good answer yet.
> >
> > Threads don't have that problem: you can use non-thread-aware code
> > with callbacks in your threaded program if you do your own locking.
> > Haskell (GHC) doesn't have that problem: it has fibers that use a
> > programming interface like C#/Python threads, but they're multiplexed
> > by user-mode code within a single OS thread. 16-bit Windows didn't
> > have that problem. Stackless and greenlet don't have that problem.
> >
> > It's a problem that can be solved by just doing the obvious thing, the
> > thing that Python already did with threads: don't define a novel
> > syntax for coroutines, but instead use the syntax that already
> > existed.
> >
> > Async/await syntax is a static type system with two types, may-yield
> > and will-not-yield. There's no provision for writing
> > generic/polymorphic code over those types, so you have to write
> > everything twice. Like any static type system it has some benefits,
> > but I don't think it's worth the cost, especially in Python, which has
> > always eschewed mandatory static typing.
> >
> > I don't know how to fix Python now that it's gone so thoroughly down
> > this path (starting with the yield keyword 18 years ago). But it's not
> > a problem that ever needed to exist. Coroutines aren't that hard.
>
> I would suggest having an "await in" operator. Or an "autowait" function:
>
> def autowait(value):
> if is_awaitable(value): return value
> async def force_await():
> return value
> return force_await()
>
> This would allow one to write "async-ready" code while calling non-async
> functions.
>
> > -- Ben
> > _______________________________________________
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