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The source code

/*
 * ForFunction.java - for loop
 * Copyright (C) 2000 Romain Guy
 * romain.guy@jext.org
 * http://www.jext.org
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either For 2
 * of the License, or any later For.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

package org.jext.dawn.loop;

import java.io.*;
import java.util.*;
import org.jext.dawn.*;

/**
 * For loop.
* Usage:
* start end variable for [code] next * @author Romain Guy */ public class ForFunction extends Function { public ForFunction() { super("for"); } public void invoke(DawnParser parser) throws DawnRuntimeException { parser.checkArgsNumber(this, 3); String var = parser.popString(); if (var.equals("needs") || var.equals("needsGlobal")) throw new DawnRuntimeException(this, parser, "you cannot use reserved keyword" + "\'needs\' or \'needsGlobal\'"); boolean word = false; for (int i = 0; i < var.length(); i++) { if (Character.isDigit(var.charAt(i)) && !word) { throw new DawnRuntimeException(this, parser, "bad for-loop counter identifier:" + var); } else word = true; } if (parser.getVariables().get(var) != null) { throw new DawnRuntimeException(this, parser, "for-loop counter identifier already exists"); } int end = (int) parser.popNumber(); int start = (int) parser.popNumber(); int innerLoop = 0; StreamTokenizer st = parser.getStream(); StringBuffer buf = new StringBuffer(); try // LONG LONG TRY { out: for( ; ; ) { switch(st.nextToken()) { case StreamTokenizer.TT_EOL: //parser.lineno++; buf.append('\n'); break; case StreamTokenizer.TT_EOF: throw new DawnRuntimeException(this, parser, "for without next"); case StreamTokenizer.TT_WORD: if (st.sval.equals("for")) innerLoop++; else if (st.sval.equals("next")) { if (innerLoop > 0) innerLoop--; else break out; } buf.append(' ' + st.sval); break; case '"': case '\'': buf.append(" \"" + DawnUtilities.unescape(st.sval) + "\""); break; case '-': buf.append(" -"); break; case StreamTokenizer.TT_NUMBER: buf.append(" " + st.nval); } } String code = buf.toString(); Function function = parser.createOnFlyFunction(code); if (start <= end) { for (int i = start; i < end; i++) { parser.getVariables().put(var, new Double(i)); function.invoke(parser); parser.getVariables().remove(var); } } else { for (int i = start - 1; i >= end; i--) { parser.getVariables().put(var, new Double(i)); function.invoke(parser); parser.getVariables().remove(var); } } } catch (IOException ioe) { throw new DawnRuntimeException(this, parser, "unexpected error occured during parsing"); } } } // End of ForFunction.java
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