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From: Terry Reedy <tjreedy@udel.edu>
Newsgroups: comp.lang.python
Subject: Re: psss...I want to move from Perl to Python
Date: Sun, 31 Jan 2016 07:28:58 -0500
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On 1/30/2016 10:22 PM, Rustom Mody wrote:
> On Sunday, January 31, 2016 at 7:27:06 AM UTC+5:30, Steven D'Aprano wrote:
>> On Sunday 31 January 2016 09:18, Gregory Ewing wrote:

>> Correct. The re module keeps a cache of the last N regexes used, for some
>> value of N (possibly 10?) so for casual use there's no real point to pre-
>> compiling other than fussiness.
>>
>> But if you have an application that makes heavy-duty use of regexes, e.g.
>> some sort of parser with dozens of distinct regexes, you might not want to
>> rely on the cache.

>>>> import re
>>>> re._MAXCACHE
> 512
>>>>
>
> Have you ever seen a program that uses 512 re's?
> I havent :-)

I do not know if the cache was always there.  It used to be smaller, 
maybe 100, then 200.

-- 
Terry Jan Reedy