[Tutor] Regex Ordering

David Perlman dperlman at wisc.edu
Tue Jul 24 07:07:30 CEST 2007

Then maybe you could write a regex that matches every regex that does  
not match itself.

ha!  sorry, couldn't resist.

On Jul 23, 2007, at 11:29 AM, Bill Campbell wrote:

> On Mon, Jul 23, 2007, James Hartley wrote:
>> On 7/23/07, Shidan <shidan at gmail.com> wrote:
>>> I'm looking for a Python module that provides methods for ordering
>>> regexes based on
>>> how general they are ( how much they match). Do I have to write it
>> Your question is relative.  Classifying which regular expression is
>> more general depends upon the other regular expressions used in
>> comparison along with the specific input.  As you change input &
>> regular expressions, the ordering will change.
> As a first cut, one might sort the regular expression strings in
> reverse order such that the longer strings are tested first.
> Bill
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