001/*
002 * Copyright (c) 2005 Einar Pehrson <einar@pehrson.nu>.
003 *
004 * This file is part of
005 * CleanSheets - a spreadsheet application for the Java platform.
006 *
007 * CleanSheets is free software; you can redistribute it and/or modify
008 * it under the terms of the GNU General Public License as published by
009 * the Free Software Foundation; either version 2 of the License, or
010 * (at your option) any later version.
011 *
012 * CleanSheets is distributed in the hope that it will be useful,
013 * but WITHOUT ANY WARRANTY; without even the implied warranty of
014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
015 * GNU General Public License for more details.
016 *
017 * You should have received a copy of the GNU General Public License
018 * along with CleanSheets; if not, write to the Free Software
019 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
020 */
021package csheets.core.formula.lang;
022
023import csheets.core.IllegalValueTypeException;
024import csheets.core.Value;
025import csheets.core.formula.Expression;
026import csheets.core.formula.Function;
027import csheets.core.formula.FunctionParameter;
028
029/**
030 * A function that returns the boolean value true.
031 * @author Einar Pehrson
032 */
033public class True implements Function {
034
035        /** The empty parameter list */
036        public static final FunctionParameter[] parameters = new FunctionParameter[]{};
037
038        /**
039         * Creates a new instance of the TRUE function.
040         */
041        public True() {}
042
043        public String getIdentifier() {
044                return "TRUE";
045        }
046
047        public Value applyTo(Expression[] arguments) throws IllegalValueTypeException {
048                return new Value(true);
049        }
050
051        public FunctionParameter[] getParameters() {
052                return parameters;
053        }
054
055        public boolean isVarArg() {
056                return false;
057        }
058}