Mark Dilger <mark.dilger@enterprisedb.com> writes:
> There are a few changes which appear correct to me, but I don't know if you expected them:
> select regexp_match('hko', '((((?<!.))))(.(\3)(\1.))');
> - regexp_match
> ---------------
> -
> + regexp_match
> +--------------------
> + {"","","",hk,"",k}
> (1 row)
Yes, this one is a consequence of 4aea704a5 (Fix semantics of regular
expression back-references). The lookbehind constraint should not be
applied within the back-ref.
> select 'nigqvigqvee' !~ '(())((\2)\2)(?:([^\W]))';
> -ERROR: invalid regular expression: invalid escape \ sequence
> + ?column?
> +----------
> + f
> +(1 row)
> +
and this one of 2a0af7fe4 (Allow complemented character class escapes
within regex brackets).
> select regexp_replace('tl', '.{0}?(((?<![^][^]{1}?)))(.)\2{6}?', 'jx', 'mt');
> regexp_replace
> ----------------
> - tl
> + jxl
> (1 row)
This looks like also a consequence of 4aea704a5.
regards, tom lane