Re: text_pattern_ops and complex regexps

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Andrew Dunstan <andrew(at)dunslane(dot)net>
Cc: Alvaro Herrera <alvherre(at)commandprompt(dot)com>, Stephen Frost <sfrost(at)snowman(dot)net>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: text_pattern_ops and complex regexps
Date: 2009-05-06 20:58:35
Message-ID: 27610.1241643515@sss.pgh.pa.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Andrew Dunstan <andrew(at)dunslane(dot)net> writes:
> Tom Lane wrote:
>> Is this demonstrable, or just speculation? The incompatibilities
>> between ARE mode and (legal) ERE patterns are pretty darn small.

> It's explicitly documented. Whether or not there is a good basis for the
> documentation I can't yet say. If that's going to be influential I will
> dig deeper.

Our fine manual asserts that the only such incompatibility is that
inside square brackets (character alternative lists), ERE mode takes
backslash as an ordinary character while ARE mode thinks it begins an
escape. Given the additional capabilities afforded by the latter
interpretation, and that every other modern regex engine on the planet
takes the latter approach *without* giving you any option, it doesn't
seem too unreasonable to ask OpenACS to join the twenty-first century
...

regards, tom lane

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Dickson S. Guedes 2009-05-06 21:01:57 Re: Patch to fix search_path defencies with pg_bench
Previous Message Joshua D. Drake 2009-05-06 20:49:10 Re: Patch to fix search_path defencies with pg_bench