[Python-Dev] Remove typing from the stdlib

[Antoine Pitrou]

On Fri, 3 Nov 2017 12:46:33 -0400
"Eric V. Smith" <eric at trueblade.com> wrote:
> On 11/3/2017 12:15 PM, Victor Stinner wrote:
> > Hi,
> > 
> > 2017-11-03 15:36 GMT+01:00 Guido van Rossum <guido at python.org>:  
> >> Maybe we should remove typing from the stdlib?
> >> https://github.com/python/typing/issues/495  
> 
> > The typing module is not used yet in the stdlib, so there is no
> > technically reason to keep typing part of the stdlib. IMHO it's
> > perfectly fine to keep typing and annotations out of the stdlib, since
> > the venv & pip tooling is now rock solid ;-)  
> 
> I'm planning on using it for PEP 557:
> https://www.python.org/dev/peps/pep-0557/#class-variables
> 
> The way the code currently checks for this should still work if typing 
> is not in the stdlib, although of course it's assuming that the name 
> "typing" really is the "official" typing library.

I don't think other modules should start relying on the typing module at
runtime.
The dataclasses module can define its own "ClassVar" thing and then I
suspect it's easy to map it to typing._ClassVar.  It seems we should be
careful not to blur the distinction between declarations that have an
effect on actual code, and typing declarations which only affect
type-checking tools.

Regards

Antoine.