[Python-Dev] Should we move to replace re with regex?

Barry Warsaw barry at python.org
Mon Aug 29 15:33:05 CEST 2011


On Aug 26, 2011, at 05:25 PM, Dan Stromberg wrote:

>from __future__ import is an established way of trying something for a while
>to see if it's going to work.

Actually, no.

The documentation says:

-----snip snip-----
__future__ is a real module, and serves three purposes:

* To avoid confusing existing tools that analyze import statements and expect
  to find the modules they’re importing.
* To ensure that future statements run under releases prior to 2.1 at least
  yield runtime exceptions (the import of __future__ will fail, because there
  was no module of that name prior to 2.1).
* To document when incompatible changes were introduced, and when they will be
  — or were — made mandatory. This is a form of executable documentation, and
  can be inspected programmatically via importing __future__ and examining its
  contents.
-----snip snip-----

So, really the __future__ module is a way to introduce accepted but
incompatible changes in a controlled way, through successive releases.  It's
never been used to introduce experimental features that might be removed if
they don't work out.

Cheers,
-Barry


More information about the Python-Dev mailing list