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/*
 * eXist-db Open Source Native XML Database
 * Copyright (C) 2001 The eXist-db Authors
 *
 * [email protected]
 * http://www.exist-db.org
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */
package org.exist.xquery;

import org.exist.xquery.util.ExpressionDumper;
import org.exist.xquery.value.Item;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.Type;

/**
 * Represents an empty sequence constructor: ()
 */
public class EmptySequenceExpr extends AbstractExpression {

    public EmptySequenceExpr(XQueryContext context) {
        super(context);
    }

    @Override
    public void analyze(AnalyzeContextInfo contextInfo) throws XPathException {
    }

    @Override
    public Sequence eval(Sequence contextSequence, Item contextItem) throws XPathException {
        return Sequence.EMPTY_SEQUENCE;
    }

    @Override
    public int returnsType() {
        return Type.EMPTY;
    }

    @Override
    public Cardinality getCardinality() {
        return Cardinality.EMPTY_SEQUENCE;
    }

    @Override
    public void dump(ExpressionDumper dumper) {
        dumper.display("()");
    }
}