EventContextHash.h

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/***********************************************************************************\
* (c) Copyright 1998-2019 CERN for the benefit of the LHCb and ATLAS collaborations *
*                                                                                   *
* This software is distributed under the terms of the Apache version 2 licence,     *
* copied verbatim in the file "LICENSE".                                            *
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* granted to it by virtue of its status as an Intergovernmental Organization        *
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#ifndef __EVENT_CONTEXT_HASH_H
#define __EVENT_CONTEXT_HASH_H
#include "GaudiKernel/EventContext.h"
class EventContextHash {
public:
  size_t hash( const EventContext& ctx ) const {
    size_t en = ctx.evt();
    size_t es = ctx.slot();
    return en ^ ( es + ( en << 6 ) + ( en >> 2 ) );
  }
  bool equal( const EventContext& a, const EventContext& b ) const { return hash( a ) == hash( b ); }

  std::size_t operator()( const EventContext& ctx ) const { return hash( ctx ); }
  bool        operator()( const EventContext& ctx, const EventContext& ctxb ) const { return equal( ctx, ctxb ); }
};

#endif