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Class template small_vector_base



// In header: <boost/container/small_vector.hpp>

template<typename T, typename SecAlloc, typename Options> 
class small_vector_base : public boost::container::vector< T, A, Options > {
  // types
  typedef real_allocator< T, SecAlloc >::type                                                     secondary_allocator_t;
  typedef allocator_traits< secondary_allocator_t >::template portable_rebind_alloc< void >::type void_allocator_t;     
  typedef dtl::get_small_vector_opt< Options >::type                                              options_t;            
  typedef dtl::vector_for_small_vector< T, SecAlloc, Options >::type                              base_type;            
  typedef allocator_traits< secondary_allocator_t >::pointer                                      pointer;              
  typedef allocator_traits< secondary_allocator_t >::const_pointer                                const_pointer;        
  typedef allocator_traits< secondary_allocator_t >::void_pointer                                 void_pointer;         
  typedef allocator_traits< secondary_allocator_t >::const_void_pointer                           const_void_pointer;   
  typedef small_vector_allocator< T, void_allocator_t, Options >                                  allocator_type;       

  // construct/copy/destruct
  explicit small_vector_base(initial_capacity_t, std::size_t);
  template<typename AllocFwd> 
    explicit small_vector_base(initial_capacity_t, std::size_t, AllocFwd &&);
  small_vector_base & operator=(const small_vector_base &);
  small_vector_base & operator=(small_vector_base &&);

  // private member functions
  const_pointer internal_storage() const noexcept;
  pointer internal_storage() noexcept;
  base_type & as_base();
  const base_type & as_base() const;

  // public member functions
  void swap(small_vector_base &);


This class consists of common code from all small_vector<T, N> types that don't depend on the "N" template parameter. This class is non-copyable and non-destructible, so this class typically used as reference argument to functions that read or write small vectors. Since small_vector<T, N> derives from small_vector_base<T>, the conversion to small_vector_base is implicit

//Clients can pass any small_vector<Foo, N>.
void read_any_small_vector_of_foo(const small_vector_base<Foo> &in_parameter);

void modify_any_small_vector_of_foo(small_vector_base<Foo> &in_out_parameter);

void some_function()

   small_vector<Foo, 8> myvector;

   read_any_small_vector_of_foo(myvector);   // Reads myvector

   modify_any_small_vector_of_foo(myvector); // Modifies myvector


All boost::container:vector member functions are inherited. See vector documentation for details.

small_vector_base public construct/copy/destruct

  1. explicit small_vector_base(initial_capacity_t, std::size_t initial_capacity);
  2. template<typename AllocFwd> 
      explicit small_vector_base(initial_capacity_t, std::size_t capacity, 
                                 AllocFwd && a);
  3. small_vector_base & operator=(const small_vector_base & other);
  4. small_vector_base & operator=(small_vector_base && other);

small_vector_base private member functions

  1. const_pointer internal_storage() const noexcept;
  2. pointer internal_storage() noexcept;
  3. base_type & as_base();
  4. const base_type & as_base() const;

small_vector_base public member functions

  1. void swap(small_vector_base & other);