Tuple.h

Go to the documentation of this file.

/***********************************************************************************\
* (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".                                            *
*                                                                                   *
* In applying this licence, CERN does not waive the privileges and immunities       *
* granted to it by virtue of its status as an Intergovernmental Organization        *
* or submit itself to any jurisdiction.                                             *
\***********************************************************************************/
#ifndef GAUDIALG_TUPLE_H
#define GAUDIALG_TUPLE_H 1
// ============================================================================
// Include files
// ============================================================================
// STD & STL
// ============================================================================
#include <string>

// ============================================================================
// ============================================================================

// ============================================================================
// ============================================================================

#include "GaudiAlg/TupleObj.h"
#include "GaudiKernel/SmartIF.h"

namespace Tuples {

  template <class ITEM>
  class TupleItem;

  class GAUDI_API Tuple {
  public:
    Tuple( std::shared_ptr<TupleObj> tuple ) : m_tuple( std::move( tuple ) ) {}

    virtual ~Tuple() = default;

    TupleObj* operator->() const { return m_tuple.get(); }

    bool valid() const { return static_cast<bool>( m_tuple ); }

  protected:
    TupleObj* tuple() { return m_tuple.get(); }

  private:
    std::shared_ptr<TupleObj> m_tuple;
  };

  template <class ITEM>
  class TupleColumn {
  public:
    TupleColumn( std::string name, ITEM value ) : m_name( std::move( name ) ), m_value( std::move( value ) ) {}

    const std::string& name() const { return m_name; }
    const ITEM& value() const { return m_value; }

  private:
    std::string m_name;  
    ITEM        m_value; 
  };

  template <class ITEM>
  inline TupleColumn<ITEM> make_column( std::string name, const ITEM& item ) {
    return {std::move( name ), item};
  }

  template <class ITEM>
  inline TupleColumn<const ITEM*> make_column( std::string name, const ITEM* item ) {
    return {std::move( name ), item};
  }

  template <class ITEM>
  inline TupleColumn<ITEM*> make_column( std::string name, ITEM* item ) {
    return {std::move( name ), item};
  }

  template <class ITEM>
  inline TupleColumn<ITEM> Column( std::string name, const ITEM& item ) {
    return make_column( std::move( name ), item );
  }

  template <class ITEM>
  inline TupleColumn<const ITEM*> Column( std::string name, const ITEM* item ) {
    return make_column( std::move( name ), item );
  }

  template <class ITEM>
  inline TupleColumn<ITEM*> Column( std::string name, ITEM* item ) {
    return make_column( std::move( name ), item );
  }

} // namespace Tuples

// ============================================================================
// ============================================================================
template <class ITEM>
inline Tuples::Tuple& operator<<( Tuples::Tuple& tuple, const Tuples::TupleColumn<ITEM>& item ) {
  if ( !tuple.valid() ) return tuple; // no action for invalid tuple
  tuple->column( item.name(), item.value() )
      .orThrow( "Failed to fill the tuple", "operator<<( Tuples::Tuple&, ...)" )
      .ignore();
  return tuple;
}
// ============================================================================

// ============================================================================
// THe END
// ============================================================================
#endif // GAUDIALG_TUPLE_H