[stdlib-sig] standardizing the deprecation policy (and how noisy they are)

[Yuvgoog Greenle]

from http://eight.pairlist.net/pipermail/geeklog-devel/2008-December/003950.html
> FYI: When pulling from / pushing to the Mercurial repository, you may
see warning messages like these:
[snip]
> You can ignore them for now - things should work just fine nonetheless.
>
> A Python upgrade on the webserver broke the repository viewer and
> after repairing this, you now get these messages. I guess we'll have
> to upgrade to Mercurial 1.1 eventually.
>
> bye, Dirk

What would happen if a single untested mercurial feature just broke? I
hope you realize this IS going to happen. Someone, somewhere is going
to one day see his code just breaking without warning.

If the warnings are annoying to you, lengthen the deprecation period
so the day of magic breakage will be the day the annoying warning
starts. People who are annoyed by warnings have no point in the
argument except for shortening the cycle of change which is something
I noticed python is against nowadays.


== a visualization ==
today:
    working, working*, warning, breaking!

Guido suggests:
    working, working*, working*, breaking!

MIchael Foord suggests a win-win proposal:
    working, working*, working*, warning, breaking!


* a special flag is needed for seeing silent warnings

--yuv