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Struct template derivation_value_traits



// In header: <boost/intrusive/derivation_value_traits.hpp>

template<typename T, typename NodeTraits, link_mode_type LinkMode = safe_link> 
struct derivation_value_traits {
  // types
  typedef NodeTraits                                                                   node_traits;    
  typedef T                                                                            value_type;     
  typedef node_traits::node                                                            node;           
  typedef node_traits::node_ptr                                                        node_ptr;       
  typedef node_traits::const_node_ptr                                                  const_node_ptr; 
  typedef pointer_traits< node_ptr >::template rebind_pointer< value_type >::type      pointer;        
  typedef pointer_traits< node_ptr >::template rebind_pointer< constvalue_type >::type const_pointer;  
  typedef boost::intrusive::pointer_traits< pointer >::reference                       reference;      
  typedef boost::intrusive::pointer_traits< const_pointer >::reference                 const_reference;

  // public static functions
  static node_ptr to_node_ptr(reference) noexcept;
  static const_node_ptr to_node_ptr(const_reference) noexcept;
  static pointer to_value_ptr(node_ptr) noexcept;
  static const_pointer to_value_ptr(const_node_ptr) noexcept;

  // public data members
  static const link_mode_type link_mode;


This value traits template is used to create value traits from user defined node traits where value_traits::value_type will derive from node_traits::node

derivation_value_traits public static functions

  1. static node_ptr to_node_ptr(reference value) noexcept;
  2. static const_node_ptr to_node_ptr(const_reference value) noexcept;
  3. static pointer to_value_ptr(node_ptr n) noexcept;
  4. static const_pointer to_value_ptr(const_node_ptr n) noexcept;