Combine negative lookbehind and negative lookahead
How can I combine negative lookbehind (?<!) and negative lookahead (?!) with an AND?
I want to find the word big, but only if it is not inside ( AND )
The problem is that I can't find big either when one of the brackets is there
Demo
https://regex101.com/r/tNC8NX/4
Regex
(?<!\()big(?!.*\))
Test Data
Should Match: I like big cakes
Should Match: I like (big cakes
Should Match: I like big) cakes
Should Match: I like xx big xx cakes
Should Match: I like ( xx big xx cakes
Should Match: I like xx big xx) cakes
Should not Match: I like (big) cakes
Should not Match: I like (xx big xx) cakes
Edit: With .Net/C#
CodePudding user response：
Since .NET regex allows variable-width lookbehind patterns you can use
(?<!\((?=[^()\n]*\))[^()\n]*)big
See the regex demo.
Note the \ns are only necessary when you need to match on a per-line basis. Remove all \ns when you need the pattern to work with standalone texts.
Details:
(?<!\((?=[^()\n]*\))[^()\n]*)- a negative lookbehind that fails the match if there is a(char and then zero or more chars other than parentheses and a newline immediately on the left, that is not immediately followed with any zero or more chars other than parentheses and a newline and then a)charbig-bigchar sequence.
CodePudding user response：
If you want to take balanced parenthesis into account, you can use match those using balancing groups and then use an alternation | and capture the word \b(big)\b in capture group 1.
\((?>\((?<open>)|[^\r\n()] |\)(?<-open>))*(?(open)(?!))\)|\b(big)\b
See a .NET regex demo.