Perl regex: remove everything (including line breaks) until a match is found
Apologies for the simple question. I don't clean text开发者_如何学运维 or use regex often.
I have a large number of text files in which I want to remove every line until my regex finds a match. There's usually about 15 lines of fluff before I find a match. I was hoping for a perl one-liner that would look like this:
perl -p -i -e "s/.*By.unanimous.vote//g" *.txt
But this doesn't work.
Thanks
Solution using the flip-flop operator:
perl -pi -e '$_="" unless /By.unanimous.vote/ .. 1' input-files
Shorter solution that also uses the x=!!
pseudo operator:
per -pi -e '$_ x=!! (/By.unanimous.vote/ .. 1)' input-files
Have a try with:
If you want to get rid until the last By.unanimous.vote
perl -00 -pe "s/.*By.unanimous.vote//s" inputfile > outputfile
If you want to get rid until the first By.unanimous.vote
perl -00 -pe "s/.*?By.unanimous.vote//s" inputfile > outputfile
Try something like:
perl -pi -e "$a=1 if !$a && /By\.unanimous\.vote/i; s/.*//s if !$a" *.txt
Should remove the lines before the matched line. If you want to remove the matching line also you can do something like:
perl -pi -e "$a=1 if !$a && s/.*By\.unanimous\.vote.*//is; s/.*//s if !$a" *.txt
Shorter versions:
perl -pi -e "$a++if/By\.unanimous\.vote/i;$a||s/.*//s" *.txt
perl -pi -e "$a++if s/.*By\.unanimous\.vote.*//si;$a||s/.*//s" *.txt
You haven't said whether you want to keep the By.unanimous.vote
part, but it sounds to me like you want:
s/[\s\S]*?(?=By\.unanimous\.vote)//
Note the missing g
flag and the lazy *?
quantifier, because you want to stop matching once you hit that string. This should preserve By.unanimous.vote
and everything after it. The [\s\S]
matches newlines. In Perl, you can also do this with:
s/.*?(?=By\.unanimous\.vote)//s
Solution using awk
awk '/.*By.unanimous.vote/{a=1} a==1{print}' input > output
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