Hi, Nick. After thinking about relationship between PEP 538 and 540 in two days, I came up with idea which removes locale coercion by default from PEP 538, it does just enables UTF-8 mode and show warning about C locale.
Of course, this idea is based on PEP 540. There are no "If PEP 540 is rejected". How do you think? If it make sense, I want to postpone PEP 538 until PEP 540 is accepted or rejected, or merge PEP 538 into PEP 540. ## Background Locale coercion in current PEP 538 has some downsides: * If user set `LANG=C LC_DATE=ja_JP.UTF-8`, locale coercion may overrides LC_DATE. * It makes behavior divergence between standalone and embedded Python. * Parent Python process may use utf-8:surrogateescape, but child process Python may use utf-8:strict. (Python 3.6 uses ascii:surrogateescape in both of parent and children). On the other hand, benefits from locale coercion is restricted: * When locale coercion succeeds, warning is always shown. To hide the warning, user must disable coercion in some way. (e.g. use UTF-8 locale explicitly, or set PYTHONCOERCECLOCALE=0). So I feel benefit / complexity ratio of locale coercion is less than UTF-8 mode. But locale coercion works nice on Android. And there are some Android-like Unix systems (container or small device) that C.UTF-8 is always proper locale. ## Rough spec * Make Android-style locale coercion (forced, no warning) is now build option. Some users who build Python for container or small device may like it. * Normal Python build doesn't change locale. When python executable is run in C locale, show locale warning. locale warning can be disabled as current PEP 538. * User can disable automatic UTF-8 mode by setting PYTHONUTF8=0 environment variables. User can hide warning by setting PYTHONUTF8=1 too. On Fri, May 5, 2017 at 10:21 PM, INADA Naoki <songofaca...@gmail.com> wrote: > On Fri, May 5, 2017 at 1:25 AM, Antoine Pitrou <solip...@pitrou.net> wrote: >> On Thu, 4 May 2017 11:24:27 +0900 >> INADA Naoki <songofaca...@gmail.com> wrote: >>> Hi, Nick and all core devs who are interested in this PEP. >>> >>> I'm reviewing PEP 538 and I want to accept it in this month. >>> It will reduces much UnicodeError pains which server-side OPs facing. >>> Thank you Nick for working on this PEP. >>> >>> If you have something worrying about this PEP, please post a comment >>> soon. If you don't have enough time to read entire this PEP, feel free to >>> ask a question about you're worrying. >> >> From my POV, it is problematic that the behaviour outlined in PEP 538 >> (see Abstract section) varies depending on the adoption of another PEP >> (PEP 540). >> >> If we want to adopt PEP 538 before pronouncing on PEP 540, then PEP 538 >> should remove all points conditional on PEP 540 adoption, and PEP 540 >> should later be changed to adopt those removed points as PEP >> 540-specific changes. >> >> Regards >> >> Antoine. >> > > Fair enough. I stop hurrying about PEP 538 and start reviewing PEP 540. > > Thanks, _______________________________________________ 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
