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[Python-Dev] Re-introduce caching for _strptime.py for 2.3.1?

Brett C. bac at OCF.Berkeley.EDU
Tue Aug 5 20:59:43 EDT 2003 
Tim Peters wrote:

> [Brett, on strptime changes]
> 
>>...
>>My question is whether I should backport any of this.
> 
> 
> I'm with Raymond:  yes.  Ripping out the cache for 2.3 final was a
> time-pressure bugfix that wouldn't have been needed had you had another day
> to repair it correctly.  I'm not so keen on adding complications beyond that
> for "thread safety", though, as locale is inherently thread-insane in the
> absence of a user-implemented locking protocol (but since most programs will
> at worst change locale once at the start, worry about threads is mostly
> wasted regardless).
> 

OK, having two people whose opinions I trust say I should add it back in 
I will.  What I will do is diff back to the last version that had 
caching, re-implement the fix for the bug (it was like four lines of 
code that are brain-dead simple) and then apply that to the 2.3.x branch.

I won't make any changes for the sake of thread-safety to LocaleTime and 
such.  There is a possibility of some weird race condition since I cache 
an instance of TimeRE and a dict of compiled regexes that is dependent 
on TimeRE, but I am having a hard time coming up with an issue outside 
of locale funkiness so I won't worry about it with 2.3.x (dealt with in 
2.4 as a safety precaution).

-Brett
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