--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/xmlpatterns/expr/qtruthpredicate_p.h	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,112 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtXmlPatterns module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+
+#ifndef Patternist_TruthPredicate_H
+#define Patternist_TruthPredicate_H
+
+#include "qgenericpredicate_p.h"
+
+QT_BEGIN_HEADER
+
+QT_BEGIN_NAMESPACE
+
+namespace QPatternist
+{
+    /**
+     * @short A predicate which is optimized for filter expressions that
+     * are of type @c xs:boolean.
+     *
+     * @author Frans Englich <frans.englich@nokia.com>
+     * @ingroup Patternist_expressions
+     */
+    class TruthPredicate : public GenericPredicate
+    {
+    public:
+        /**
+         * Creates a TruthPredicate which filters the items from the @p sourceExpression
+         * through @p predicate.
+         *
+         * This constructor is protected. The proper way to create predicates is via the static
+         * create() function.
+         */
+        TruthPredicate(const Expression::Ptr &sourceExpression,
+                       const Expression::Ptr &predicate);
+
+        inline Item mapToItem(const Item &item, const DynamicContext::Ptr &context) const
+        {
+            Q_ASSERT_X(false, Q_FUNC_INFO, "This is practically dead code because it never gets called in GenericPredicate, "
+                                           "which binds to its own mapToItem for completely legitime reasons.");
+            if(m_operand2->evaluateEBV(context))
+                return item;
+            else
+                return Item();
+        }
+
+        inline Item::Iterator::Ptr map(const Item &item,
+                                       const DynamicContext::Ptr &context) const
+        {
+            Q_ASSERT_X(false, Q_FUNC_INFO, "I don't expect this function to be called, for the same reasons as above.");
+            if(m_operand2->evaluateEBV(context))
+                return makeSingletonIterator(item);
+            else
+                return CommonValues::emptyIterator;
+        }
+
+        virtual SequenceType::List expectedOperandTypes() const;
+        virtual ExpressionVisitorResult::Ptr accept(const ExpressionVisitor::Ptr &visitor) const;
+    };
+}
+
+QT_END_NAMESPACE
+
+QT_END_HEADER
+
+#endif