Re: Inside the Regex Engine

Andrew Dunstan <andrew(at)dunslane(dot)net> wrote:
> Tom Lane wrote:
>
>>david(at)fetter(dot)org (David Fetter) writes:
>>
>>
>>>While PL/Perl is great, it's not available everywhere, and I'd like
>>>to be able to grab atoms from a regex match in, say, a SELECT. Is
>>>there some way to get access to them?
>>
>>There's a three-parameter variant of substring() that allows
>>extraction of a portion of a regex match --- unfortunately it uses
>>SQL99's brain-dead notion of regex, which will not satisfy any Perl
>>weenie :-(
>>
>>I think it'd be worth our while to define some comparable
>>functionality that depends only on the POSIX regex engine ...
>
> substitute should be relatively straightforward, I guess; split and
> match maybe less so - what do you return? An array?

That would be great.

> Or you could require an explicit subscript to get a particular
> return value as in split_part(), which would be potentially
> inefficient if you want more than one (although I guess results
> could be cached).

That'd be good, too.

Cheers
D
--
David Fetter david(at)fetter(dot)org http://fetter.org/
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