[Python-Dev] PEP 550 v4

[Yury Selivanov]

On Sat, Aug 26, 2017 at 4:45 PM, francismb <francismb at email.de> wrote:
[..]

> it's by design that the execution context for new threads to be empty or
> should it be possible to set it to some initial value? Like e.g:
>
>      var = new_context_var('init')
>
>      def sub():
>          assert var.lookup() == 'init'
>          var.set('sub')
>
>      def main():
>          var.set('main')
>
>          thread = threading.Thread(target=sub)
>          thread.start()
>          thread.join()
>
>          assert var.lookup() == 'main'


Yes, it's by design.

With PEP 550 APIs it's easy to subclass threading.Thread or
concurrent.futures.ThreadPool to make them capture the EC.

Yury