On Sat, 23 Jun 2018, ND via Pcre-dev wrote: > The fact of error confusing me because there is no error happens without > "replace": > > > PCRE2 version 10.31 2018-02-12 > /(?<=\K.)/g > ab > 0: a > 0: b
pcre2_substitute(), which is what "replace" calls, processes the string from left to right. It finds a match, copies the preceding text to the output, then copies the replacement, then starts the next search at tne end point of the previous match. By using \K in a lookbehind assertion at the start of your pattern, you have moved the start of the next match to the left of the end of the previous match. This case is not supported by pcre2_substitute(). Perl gets this wrong too. I tried your example and it sent Perl into a loop and I had to power-cycle my maching in order to recover. Philip -- Philip Hazel -- ## List details at https://lists.exim.org/mailman/listinfo/pcre-dev
