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diff --git a/libkcal/assignmentvisitor.h b/libkcal/assignmentvisitor.h
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+/*
+    Copyright (c) 2009 Kevin Krammer <kevin.krammer@gmx.at>
+
+    This library is free software; you can redistribute it and/or modify it
+    under the terms of the GNU Library General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or (at your
+    option) any later version.
+
+    This library 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 Library General Public
+    License for more details.
+
+    You should have received a copy of the GNU Library General Public License
+    along with this library; see the file COPYING.LIB.  If not, write to the
+    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+    02110-1301, USA.
+*/
+
+#ifndef KCAL_ASSIGNMENTVISITOR_H
+#define KCAL_ASSIGNMENTVISITOR_H
+
+#include "incidencebase.h"
+
+namespace KCal {
+
+/**
+  Helper for type correct assignment of incidences via pointers.
+
+  This class provides a way of correctly assigning one incidence to another,
+  given two IncidenceBase derived pointers. It effectively provides a virtual
+  assignment method which first type checks the two pointers to ensure they
+  reference the same incidence type, before performing the assignment.
+
+  Usage example:
+  @code
+  KCal::Incidence *currentIncidence; // assume this is set somewhere else
+  KCal::Incidence *updatedIncidence; // assume this is set somewhere else
+
+  KCal::AssignmentVisitor visitor;
+
+  // assign
+  if ( !visitor.assign(currentIncidence, updatedIncidence) ) {
+    // not of same type
+  }
+  @endcode
+
+  @author Kevin Krammer \<kevin.krammer@gmx.at\>
+ */
+class AssignmentVisitor : public IncidenceBase::Visitor
+{
+  public:
+    /**
+      Creates a visitor instance.
+     */
+    AssignmentVisitor();
+
+    /**
+      Destroys the instance.
+     */
+    virtual ~AssignmentVisitor();
+
+    /**
+      Assigns the incidence referenced by @p source to the incidence referenced
+      by @p target, first ensuring that the @p source incidence can be cast to
+      the same class as the @p target incidence.
+
+      Basically it is a virtual equivalent of
+      @code
+      *target = *source
+      @endcode
+
+      @param target pointer to the instance to assign to
+      @param source pointer to the instance to assign from
+
+      @return @c false if the two objects are of different type
+     */
+    bool assign( IncidenceBase *target, const IncidenceBase *source );
+
+    /**
+      Tries to assign to the given @p event, using the source passed to
+      assign().
+
+      @return @c false if the source passed to assign() is not an Event
+     */
+    virtual bool visit( Event *event );
+
+    /**
+      Tries to assign to the given @p todo, using the source passed to
+      assign().
+
+      @return @c false if the source passed to assign() is not a Todo
+     */
+    virtual bool visit( Todo *todo );
+
+    /**
+      Tries to assign to the given @p journal, using the source passed to
+      assign().
+
+      @return @c false if the source passed to assign() is not a Journal
+     */
+    virtual bool visit( Journal *journal );
+
+    /**
+      Tries to assign to the given @p freebusy, using the source passed to
+      assign().
+
+      @return @c false if the source passed to assign() is not a FreeBusy
+     */
+    virtual bool visit( FreeBusy *freebusy );
+
+  private:
+    //@cond PRIVATE
+    class Private;
+    Private *const d;
+    //@endcond
+};
+
+}
+
+#endif
+// kate: space-indent on; indent-width 2; replace-tabs on;