An alternative that feels cleaner, though (*MARK:NAME) is supported way fewer places than named captures: 
$ perl -E'say "xxx" =~ s/(*MARK:a)^.|(*MARK:c).$|(*MARK:b)./$REGMARK/g
+r'
abc

[download]
$ python -c 'import pcre2; print(pcre2.sub("(*MARK:a)^.|(*MARK:c).$|(*
+MARK:b).", "$*MARK", "xxx"))'
abc

[download]

In reply to Re: better way to get last named capture group by ysth
in thread better way to get last named capture group by ysth

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