betweenBrackets method
Returns the content between the first matching bracket pair found, or
null if none is found.
Tries parentheses, square brackets, angle brackets, and curly braces in order.
Implementation
@useResult
String? betweenBrackets() {
if (isEmpty) {
return null;
}
// Try each bracket family in priority order, returning the first non-empty
// result. Empty content is skipped so "()" doesn't shadow a later "[x]".
final String parens = between('(', ')');
if (parens.isNotEmpty) return parens;
final String squares = between('[', ']');
if (squares.isNotEmpty) return squares;
final String angles = between('<', '>');
if (angles.isNotEmpty) return angles;
final String curlies = between('{', '}');
if (curlies.isNotEmpty) return curlies;
return null;
}