> On 10 Feb 2022, at 7:03 pm, raf <post...@raf.org> wrote:
>
> Thanks, but I'm not sure that that is material to this
> issue.
It is.
> Even with regexp, x refers to "extended
> expression syntax".
Which is a converse to "basic expression syntax", i.e. the obsolete
BRE syntax, in which "(" and "|" are ordinary characters unless escaped
"\(" or "\|", there is no support for "{n}" multiplicity or "+" for one
or more, ...
> The extensions differ between
> regexp and pcre, but not to the extent that it would
> lead to that syntax error in that pattern (as far as
> I can see).
Again, you're mistaken. Check the regex API manpages.
--
Viktor.
