Re: Manua correction

On Tue, Jul 20, 2021 at 11:03:09AM -0400, Tom Lane wrote:
> Bruce Momjian <bruce(at)momjian(dot)us> writes:
> > I really don't understand the use of "(s)" except in place where we are
> > really trying to point out the idea of one or multiple, and I don't see
> > that being significant in these cases --- can you clarify?
>
> See the example given for regexp_match:
>
> regression=# select regexp_match('foobarbequebaz', '(bar)(beque)');
> regexp_match
> --------------
> {bar,beque}
> (1 row)
>
> There's more than one parenthesized subpattern, so you get more than
> one substring in the result. So I think that change is flat out
> wrong.
>
> The places where you changed "substring(s)" to "substrings" are maybe
> not flat wrong, but I don't think they're improving the text either.
> IIRC, in most of them you get one match if you didn't use the 'g'
> flag, but possibly multiple matches if you did, and the "substring(s)"
> wording is meant to allude to that without taking the space to spell
> it out explicitly.

I see what you mean --- there can be multiple capture groups, and
multiple match processing if 'g' is used. I think the text using "(s)"
is too complex, so I spelled out the use 'g' and clarified the case of
multiple groups in a single regex.

Updated patch attached, and I used a larger line context around the
changes to clarify what was being modified.

--
Bruce Momjian <bruce(at)momjian(dot)us> https://momjian.us
EDB https://enterprisedb.com

If only the physical world exists, free will is an illusion.