On Mon, Sep 16, 2013 at 3:45 PM, Antoine Pitrou <solipsis@pitrou.net> wrote:
On Mon, 16 Sep 2013 19:06:37 +0200 Charles-François Natali <cf.natali@gmail.com> wrote:
2013/9/16 Antoine Pitrou <solipsis@pitrou.net>:
Le Sun, 15 Sep 2013 06:46:08 -0700, Ethan Furman <ethan@stoneleaf.us> a écrit :
I see PEP 428 is both targeted at 3.4 and still in draft status.
What remains to be done to ask for pronouncement?
I think I have a couple of items left to integrate in the PEP. Mostly it needs me to take a bit of time and finalize the PEP, and then have a PEP delegate (or Guido) pronounce on it.
IIRC, during the last discussion round, we were still debating between implicit stat() result caching - which requires an explicit restat() method - vs a mapping between the stat() method and a stat() syscall.
What was the conclusion?
No definite conclusion. You and Nick liked the idea of a rich stat object (returned by os.stat()) with is_dir() methods and the like: https://mail.python.org/pipermail/python-dev/2013-May/125809.html
However, nothing was done about that since then ;-)
There was also the scandir() proposal to return rich objects with optional stat-like fields, but similarly it didn't get a conclusion: https://mail.python.org/pipermail/python-dev/2013-May/126119.html
So I would like to propose the following API change:
- Path.stat() (and stat-accessing methods such as get_mtime()...) returns an uncached stat object by default
- Path.cache_stat() can be called to return the stat() *and* cache it for future use, such that any future call to stat(), cache_stat() or a stat-accessing function reuses that cached stat
In other words, only if you use cache_stat() at least once is the stat() value cached and reused by the Path object. (also, it's a per-Path decision)
Any reason why stat() can't get a keyword-only cached=True argument instead? Or have stat() never cache() but stat_cache() always so that people can choose if they want fresh or cached based on API and not whether some library happened to make a decision for them?