Regex learning.


 
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# 8  
Old 03-03-2020
I'm probably a little wrong. the non-greedy expression on the left side allows you to not check the entire string, but limit itself to the first match. hence not a greedy expression faster and that's good
remark:
I already realized that you wrote exactly that

Last edited by nezabudka; 03-03-2020 at 03:33 PM..
# 9  
Old 03-03-2020
else in PCRE work such flag (?U:). I will put a space so that it can be seen
Code:
cat file
abcdtest123^ DUMMY testabcd12234 DUMMY bla blabla12231311313blabla bla.....,,,,,bla

Code:
grep -oP '(?P<p>.*)(\^.*DUMMY\s+)\K\g<p>' file
bla blabla12231311313blabla bla.....,,,,,bla

Code:
grep -oP '(?P<p>.*)(?U:\^.*DUMMY\s+)\K\g<p>' file
testabcd12234 DUMMY bla blabla12231311313blabla bla.....,,,,,bla

Thanks for an interesting example.
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