[Python-ideas] Decorators for running a function in a Process or Thread

[Nick Coghlan]

On 1 May 2017 at 22:02, Paul Moore <p.f.moore at gmail.com> wrote:
> On 1 May 2017 at 12:13, NoxDaFox <noxdafox at gmail.com> wrote:
>>
>> I think it could be a good fit for the `concurrent.futures` module.
>> Decorated functions would return a `Future` object and run the logic in a
>> separate thread or process.
>>
>>
>> @concurrent.futures.thread
>> def function(arg, kwarg=0):
>>     return arg + kwarg
>>
>> future = function(1, kwarg=2)
>> future.result()
>
> What's the benefit over just running the function in a thread (or
> process) pool, using Executor.submit()?

It allows function designers to deliberately increase the friction of
calling the function "normally". Consider an async library, for
example - in such cases, it's useful to be able ensure that a blocking
function never runs in the *current* thread, and instead always runs
in a different one.

One of the problems for the proposal is that we don't have the notion
of a "default executor", the way we do with the default event loop in
asyncio, so functions decorated with these would need to accept an
additional parameter specifying the executor to use.

Cheers,
Nick.

-- 
Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia