On 2017-08-08, Chris Angelico <ros...@gmail.com> wrote: > On Wed, Aug 9, 2017 at 2:57 AM, Larry Martell <larry.mart...@gmail.com> wrote: >> Yeah, it does not throw for 'A|B|' - but mysql chokes on it with empty >> subexpression for regexp' I'd like to flag it before it gets to SQL. > > Okay, so your definition of validity is "what MySQL will accept". In > that case, I'd feed it to MySQL and see if it accepts it. Regexps are > sufficiently varied that you really need to use the same engine for > validation as for execution.
... but bear in mind, there have been ways of doing denial-of-service attacks with valid-but-nasty regexps in the past, and I wouldn't want to rely on there not being any now. -- https://mail.python.org/mailman/listinfo/python-list
