/*
 ***** BEGIN LICENSE BLOCK *****
 * Version: EPL 1.0/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Eclipse Public
 * License Version 1.0 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy of
 * the License at http://www.eclipse.org/legal/epl-v10.html
 *
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * Copyright (C) 2002 Anders Bengtsson <ndrsbngtssn@yahoo.se>
 * Copyright (C) 2002 Jan Arne Petersen <jpetersen@uni-bonn.de>
 * Copyright (C) 2002 Benoit Cerrina <b.cerrina@wanadoo.fr>
 * Copyright (C) 2004-2005 Thomas E Enebo <enebo@acm.org>
 * Copyright (C) 2004 Stefan Matthias Aust <sma@3plus4.de>
 * 
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the EPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the EPL, the GPL or the LGPL.
 ***** END LICENSE BLOCK *****/
package org.jruby.ast;

import java.util.List;

import org.jruby.ast.types.IArityNode;
import org.jruby.ast.visitor.NodeVisitor;
import org.jruby.lexer.yacc.ISourcePosition;
import org.jruby.runtime.Arity;

/** Represents a zero arg in a block.
 * this is never visited and is used only in an instanceof check
 * <pre>
 * do ||
 * end
 * </pre>
 *
 */
public class ZeroArgNode extends Node implements IArityNode {
    public ZeroArgNode(ISourcePosition position) {
        super(position);
    }

    public NodeType getNodeType() {
        return NodeType.ZEROARGNODE;
    }

    /**
     * @see Node#accept(NodeVisitor)
     */
    public Object accept(NodeVisitor visitor) {
    	return null; // never visited, should be ok
    }
	
    /**
     * Zero arguments...
     */
    public Arity getArity() {
        return Arity.noArguments();
    }

    public List<Node> childNodes() {
        return EMPTY_LIST;
    }
}
