Menu
I want to find the number of occurrences of XXX in my latex document that are not in the form of a command as \XXX. Therefore I am looking for occurrences that are not preceded by a backslash.
I tried the following:
grep -c -e '(?<!\)XXX' test.tex #result: grep: Unmatched ) or \)
grep -c -e '(?<!\\)XXX' test.tex #result: 0
grep -c -e "(?<!\\)XXX" test.tex #result: -bash: !\\: event not found
none of them work as intended. In fact I don't understand the last error message at all.
My test.tex contains only the following lines
%test.tex
XXX
\XXX
So the expected result is 1.
Any ideas?
Ps.: I am working in bash.
751
find (both the GNU and BSD variants) do not support lookahead/lookbehind. GNU grep only supports the POSIX basic and extended regular expression variants as well as a couple of others.
A negative lookbehind assertion asserts true if the pattern inside the lookbehind is not matched.
The good news is that you can use lookbehind anywhere in the regex, not only at the start. If you want to find a word not ending with an “s”, you could use \b\w+(? <! s)\b.
Negative lookbehinds seem to be the only answer, but JavaScript doesn't has one. Consider posting the regex as it would look with a negative lookbehind; that may make it easier to respond. @WiktorStribiżew : Look-behinds were added in the 2018 spec. Chrome supports them, but Firefox still hasn't implemented the spec.
Neither standard nor extended regular expressions support the look behind. Use Perl compatible regexes:
grep -P '(?<!\\)xxx' test.tex
Try to use
grep -P '(?<!\\)\bXXX\b' test.tex
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
