rem: bool KMSearchRule::isEmpty() const { bool ok = false;  if ( mField == "<size>" || mField == "<age in days>" ) mContents.toInt( &ok ); else ok = true;  return mField.stripWhiteSpace().isEmpty() || mContents.isEmpty() || !ok;
add: bool KMSearchRuleString::isEmpty() const { return field().stripWhiteSpace().isEmpty() || contents().isEmpty();
context: bool KMSearchRule::isEmpty() const {  bool ok = false;  if ( mField == "<size>" || mField == "<age in days>" )    mContents.toInt( &ok );  else    ok = true;  return mField.stripWhiteSpace().isEmpty()    || mContents.isEmpty() || !ok;}