Regular Expressions 101

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/
"(?!(\{\{[^\s]*\}\}\s*)+").*"
/
gm
" matches the character " with index 3410 (2216 or 428) literally (case sensitive)
Negative Lookahead
(?!(\{\{[^\s]*\}\}\s*)+")
Assert that the Regex below does not match
1st Capturing Group
(\{\{[^\s]*\}\}\s*)+
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
\{ matches the character { with index 12310 (7B16 or 1738) literally (case sensitive)
\{ matches the character { with index 12310 (7B16 or 1738) literally (case sensitive)
Match a single character not present in the list below
[^\s]
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
\} matches the character } with index 12510 (7D16 or 1758) literally (case sensitive)
\} matches the character } with index 12510 (7D16 or 1758) literally (case sensitive)
\s
matches any whitespace character (equivalent to [\r\n\t\f\v ])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
" matches the character " with index 3410 (2216 or 428) literally (case sensitive)
.
matches any character (except for line terminators)
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
" matches the character " with index 3410 (2216 or 428) literally (case sensitive)
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
gm

Test String