The \[.*?\]\[2\] pattern works like this:
\[– finds the leftmost[(as the regex engine processes the string input from left to right).*?– matches any 0+ chars other than line break chars, as few as possible, but as many as needed for a successful match, as there are subsequent patterns, see below\]\[2\]–][2]substring.
So, the .*? gets expanded upon each failure until it finds the leftmost ][2]. Note the lazy quantifiers do not guarantee the “shortest” matches.
Solution
Instead of a .*? (or .*) use negated character classes that match any char but the boundary char.
\[[^\]\[]*\]\[2\]
See this regex demo.
Here, .*? is replaced with [^\]\[]* – 0 or more chars other than ] and [.
Other examples:
- Strings between angle brackets:
<[^<>]*>matches<...>with no<and>inside - Strings between parentheses:
\([^()]*\)matches(...)with no(and)inside - Strings between double quotation marks:
"[^"]*"matches"..."with no"inside - Strings between curly braces:
\{[^{}]*}matches"..."with no"inside
In other situations, when the starting pattern is a multichar string or complex pattern, use a tempered greedy token, (?:(?!start).)*?. To match abc 1 def in abc 0 abc 1 def, use abc(?:(?!abc).)*?def.