delete method
Deletes characters from the specified range.
start
the starting index (inclusive)
end
the ending index (exclusive)
Returns this StringBuilder for method chaining
Implementation
StringBuilder delete(int start, int end) {
String current = _buffer.toString();
if (start < 0 || end > current.length || start > end) {
throw RangeError('Invalid range: $start to $end');
}
String before = current.substring(0, start);
String after = current.substring(end);
_buffer.clear();
_buffer.write(before);
_buffer.write(after);
return this;
}