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diff --git a/libjava/gnu/xml/xpath/BooleanFunction.java b/libjava/gnu/xml/xpath/BooleanFunction.java
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+/* BooleanFunction.java -- 
+   Copyright (C) 2004 Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath 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 version 2, or (at your option)
+any later version.
+
+GNU Classpath 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 GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+02111-1307 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+package gnu.xml.xpath;
+
+import java.util.List;
+import org.w3c.dom.Node;
+
+/**
+ * The <code>boolean</code> function converts its argument to a boolean as
+ * follows:
+ * <ul>
+ * <li>a number is true if and only if it is neither positive or negative
+ * zero nor NaN</li>
+ * <li>a node-set is true if and only if it is non-empty</li>
+ * <li>a string is true if and only if its length is non-zero</li>
+ * <li>an object of a type other than the four basic types is converted to a
+ * boolean in a way that is dependent on that type</li>
+ * </ul>
+ *
+ * @author <a href='mailto:dog@gnu.org'>Chris Burdess</a>
+ */
+final class BooleanFunction
+  extends Expr
+{
+
+  final Expr arg;
+  
+  BooleanFunction(List args)
+  {
+    this((Expr) args.get(0));
+  }
+
+  BooleanFunction(Expr arg)
+  {
+    this.arg = arg;
+  }
+  
+  public Object evaluate(Node context, int pos, int len)
+  {
+    Object val = arg.evaluate(context, pos, len);
+    return _boolean(context, val) ? Boolean.TRUE : Boolean.FALSE;
+  }
+
+  public Expr clone(Object context)
+  {
+    return new BooleanFunction(arg.clone(context));
+  }
+  
+  public String toString()
+  {
+    return "boolean(" + arg + ")";
+  }
+  
+}