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diff --git a/src/main/java/io/devnulllabs/openjava/syntax/IterationRule.java b/src/main/java/io/devnulllabs/openjava/syntax/IterationRule.java
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+++ b/src/main/java/io/devnulllabs/openjava/syntax/IterationRule.java
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+/*
+ * IterationRule.java
+ *
+ * comments here.
+ *
+ * @author   Michiaki Tatsubori
+ * @version  %VERSION% %DATE%
+ * @see      java.lang.Object
+ *
+ * COPYRIGHT 1998 by Michiaki Tatsubori, ALL RIGHTS RESERVED.
+ */
+package io.devnulllabs.openjava.syntax;
+
+
+import io.devnulllabs.openjava.ptree.ObjectList;
+import io.devnulllabs.openjava.ptree.ParseTree;
+
+
+/**
+ * The class <code>IterationRule</code> represents iterative syntax
+ * rule.
+ * <p>
+ * Suppose there's a syntax rule A.  This class can represents
+ * the syntax ( A )* or ( A )+
+ *
+ * @author   Michiaki Tatsubori
+ * @version  1.0
+ * @since    $Id: IterationRule.java,v 1.2 2003/02/19 02:54:31 tatsubori Exp $
+ * @see java.lang.Object
+ */
+public class IterationRule extends AbstractSyntaxRule
+{
+    private SyntaxRule elementRule;
+    private boolean allowsEmpty;
+
+    /**
+     * Allocates a new rule representing iterations of a given rule.
+     *
+     * @param elementRule  a rule to iterate
+     * @param allowsEmpty  a flag to allow 0 iteration if it is true.
+     */
+    public IterationRule( SyntaxRule elementRule, boolean allowsEmpty ) {
+    this.elementRule = elementRule;
+    this.allowsEmpty = allowsEmpty;
+    }
+
+    /**
+     * Allocates a new rule representing iterations of a given rule
+     * not allowing 0 iteration.
+     *
+     * @param elementRule  a rule to iterate
+     */
+    public IterationRule( SyntaxRule elementRule ) {
+    this( elementRule, false );
+    }
+
+    /**
+     * Consumes token source.
+     *
+     * @param token_src  token source.
+     * @return  null if this fails to consume a syntax tree represented
+     * by this object.  Otherwise it returns <code>ObjectList</code> object.
+     */
+    public ParseTree consume( TokenSource token_src )
+    throws SyntaxException
+    {
+    ObjectList result = new ObjectList();
+    if (! allowsEmpty) {
+        result.add( elementRule.consume( token_src ) );
+    }
+    while (elementRule.lookahead( token_src )) {
+        ParseTree elem = elementRule.consume( token_src );
+        result.add( elem );
+    }
+    return result;
+    }
+
+}