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## Class template small_vector

boost::container::small_vector

## Synopsis

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

    template<typename T, std::size_t N, typename Allocator = new_allocator<T> >
    class small_vector :
      public boost::container::small_vector_base< T, Allocator >
    {
    public:
      // construct/copy/destruct
      small_vector();
      explicit small_vector(size_type);
      explicit small_vector(const allocator_type &);
      small_vector(size_type, const allocator_type &);
      small_vector(const small_vector &);
      small_vector(const small_vector &, const allocator_type &);
      small_vector(small_vector &&);
      small_vector(small_vector &&, const allocator_type &);
      small_vector(std::initializer_list< value_type >,
                   const allocator_type & = allocator_type());
      small_vector & operator=(const small_vector &);
      small_vector & operator=(small_vector &&);

      // public member functions
      void swap(small_vector &);
    };

## Description

small_vector a vector-like container optimized for the case when it contains few elements. It contains some preallocated elements in-place, which allows it to avoid the use of dynamic storage allocation when the actual number of elements is below that preallocated threshold.

`small_vector<T, N, Allocator>` is convertible to `small_vector_base<T, Allocator>` that is independent from the preallocated element capacity, so client code does not need to be templated on that N argument.

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

### Template Parameters

1.     typename T

   The type of object that is stored in the `small_vector`

2.     std::size_t N

   The number of preallocated elements stored inside `small_vector`. It shall be less than Allocator::max_size();

3.     typename Allocator = new_allocator<T>

   The allocator used for memory management when the number of elements exceeds N.

### `small_vector` public construct/copy/destruct

1.     small_vector();

2.     explicit small_vector(size_type n);

3.     explicit small_vector(const allocator_type & a);

4.     small_vector(size_type n, const allocator_type & a);

5.     small_vector(const small_vector & other);

6.     small_vector(const small_vector & other, const allocator_type & a);

7.     small_vector(small_vector && other);

8.     small_vector(small_vector && other, const allocator_type & a);

9.     small_vector(std::initializer_list< value_type > il,
                    const allocator_type & a = allocator_type());

10.     small_vector & operator=(const small_vector & other);

11.     small_vector & operator=(small_vector && other);

### `small_vector` public member functions

1.     void swap(small_vector & other);