Also, as for dataclasses specifically, since it may become as pervasive as namedtuples, we probably want it to be as light-weight as possible. Which will be harder to achieve if its *API* depends on the typing machinery.
Regards Antoine. Le 03/11/2017 à 19:04, Paul Moore a écrit : > On 3 November 2017 at 17:47, Antoine Pitrou <solip...@pitrou.net> wrote: >> On Fri, 3 Nov 2017 12:46:33 -0400 >> "Eric V. Smith" <e...@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 <gu...@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. > > I'm looking forward to the dataclasses module, and I'm perfectly OK > with the way that it uses type annotations to declare attributes. I > also don't have a problem with it relying on the typing module - but > *only* if the typing module is in the stdlib. I don't think it's good > if a standard feature needs an external library for some of its > functionality. > > So I guess the point is, if we're considering moving typing out of the > stdlib, then what's the impact on PEP 557? > > Personally, I don't use type annotations myself yet, but I've used > code that does and I'm considering looking into them - for a variety > of reasons, documentation, IDE support, and the ability to type check > my code via mypy. If typing moves out of the stdlib, I'd be much less > inclined to do so - adding a runtime dependency is a non-trivial cost > in terms of admin for deployment, handling within my (peculiar, if you > want to debate workflow) development workflow, etc. Working out how to > add type annotations *without* them being a runtime dependency (just > at test-time) is too much work. So I am concerned that if we move > typing out of the stdlib, it'll reduce adoption rates. > > Paul > _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com