/cvmfs/atlas.cern.ch/repo/sw/ASG/AnalysisBase/2.4.31/xAODCore/xAODCore/tools/AuxPersInfo.h

// Dear emacs, this is -*- c++ -*-
// $Id: AuxPersInfo.h 634134 2014-12-05 19:27:41Z ssnyder $
#ifndef XAODCORE_TOOLS_AUXPERSINFO_H
#define XAODCORE_TOOLS_AUXPERSINFO_H

// System include(s):
#include <stdexcept>

// EDM include(s):
#include "AthContainersInterfaces/IAuxTypeVector.h"

namespace xAOD {

   template< class T >
   class AuxPersInfo : public SG::IAuxTypeVector {

   public:
      typedef T& info_type;

      AuxPersInfo( info_type info ) : m_info( info ) {}

      virtual SG::IAuxTypeVector* clone() const {
        return new AuxPersInfo<T>(*this);
      }

      virtual void* toPtr() {
         return &m_info;
      }
      virtual void* toVector() {
         return &m_info;
      }
      virtual size_t size() const {
         return 1;
      }
      virtual void resize( size_t sz ) {
         if( sz != 1 ) {
            throw std::runtime_error( "Calling resize with != 1 on a "
                                      "non-vector" );
         }
      }
      virtual void reserve( size_t sz ) {
         if( sz != 1 ) {
            throw std::runtime_error( "Calling reserve with != 1 on a "
                                      "non-vector" );
         }
      }
      virtual void shift( size_t /*pos*/, ptrdiff_t /*offs*/ ) {
         throw std::runtime_error( "Calling shift on a non-vector" );
      }

      virtual const std::type_info* objType() const {
         return &typeid(T);
      }

   private:
      info_type m_info;

   }; // class AuxPersInfo

} // namespace xAOD

#endif // XAODCORE_TOOLS_AUXPERSINFO_H

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