--| Copyright (c) 1993-2020 University of Southern California, Eiffel Software and contributors. --| All rights reserved. --| Your use of this work is governed under the terms of the GNU General --| Public License version 2. class CHILD create make feature make do create attribute_field; end; weasel do end is_valid: BOOLEAN do Result := attribute_field.valid; end attribute_field: TEST1; invariant always_valid: is_valid; end