- covariant SemanticsSortKey other
The implementation of compareTo.
The argument is guaranteed to be of the same type as this object and have the same name.
The method should return a negative number if this object comes earlier in the sort order than the argument; and a positive number if it comes later in the sort order. Returning zero causes the system to use default sort order.
@protected int doCompare(covariant SemanticsSortKey other);