I am trying to create a regex to match any tags not including [first].
# Trying to match:
# [second]
# [first.second]
# [first.third]
[first]
# something = else
[second]
test = yes
[first.second]
[first.third]
I was trying ^\[((?!first).*)\]$
https://regex101.com/r/1fz1CW/1
And this seems to match [second] in the example above but I can't figure out why it doesn't match [first.second] or [first.third] I was thinking I may need word boundaries, but I can't seem to get them to work.
Use
^\[((?!first\])[^\]\[]*)\]$
See regex proof.
EXPLANATION
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^ the beginning of the string
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\[ '['
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( group and capture to \1:
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(?! look ahead to see if there is not:
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first 'first'
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\] ']'
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) end of look-ahead
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[^\]\[]* any character except: '\]', '\[' (0 or
more times (matching the most amount
possible))
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) end of \1
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\] ']'
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$ before an optional \n, and the end of the
string