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

[Philip Jenvey]

On Nov 8, 2009, at 1:26 PM, Brett Cannon wrote:

> During the moratorium PEP discussions Guido said he wanted to quiet
> down deprecation warnings. I see there being two options on this.
>
> One is to keep things as is, but to require two releases with
> PendingDeprecationWarning so there are three years of
> silent-by-default warnings to update your code. But that last release
> before removal came would still be noisy.

DeprecationWarnings are annoying but for good enough reason. I'd  
rather encourage folks to deal with them sooner rather than later,  
which is what PendingDeprecationWarnings are for.

So I like requiring two (or one is enough for me) releases of  
PendingDeprecationWarnings, but combined with the requirement that any  
new warnings be explicitly documented in their own section of the  
release's What's New doc. That section should also remind you how to  
enable PendingDeprecationWarnings via the command line and the  
warnings module itself. I'd also consider adding a PYTHONWARNINGS  
environment variable to ease toggling of warnings when running Python  
code via an external script.

--
Philip Jenvey