package schemeFactory;

/**
 * Abstract factory to manufacture empty and non-empty AList objects.
 */
public interface IListFactory {
    /**
     * Creates a concrete empty AList object.
     * @return AList.
     */
    public AList makeEmptyList();

    /**
     * Creates a concrete non-empty AList.
     * @param first the first data element for the AList
     * @param tail != null the rest for the AList
     * @return AList
     */
    public AList makeNEList(Object first, AList tail);
}