https://bugs.exim.org/show_bug.cgi?id=2792
--- Comment #1 from Philip Hazel <philip.ha...@gmail.com> --- Perl used to allow \K in lookarounds. I am aware that it has changed, and this is documented in pcre2pattern: "Perl used to document that the use of \K within lookaround assertions is "not well defined", but from version 5.32.0 Perl does not support this usage at all. In PCRE2, \K is acted upon when it occurs inside positive assertions, but is ignored in negative assertions." I suspect that changing PCRE2 will break a few patterns and annoy some people without achieving very much, so I am not very keen on making a change, except perhaps to give an error instead of ignoring \K in negative lookarounds. -- You are receiving this mail because: You are on the CC list for the bug. -- ## List details at https://lists.exim.org/mailman/listinfo/pcre-dev