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package org.hsqldb;

/**
 * Interface for SQL set function values.
 * @author Fred Toussi (fredt@users dot sourceforge.net)
 * @version 2.5.1
 * @since 2.4.1
 *
 */
public interface SetFunction {

    void add(Object itemLeft, Object itemRight);

    void add(Object item);

    void addGroup(SetFunction item);

    Object getValue();

    void reset();
}
