Adaptor around a STL sequence container.
Declared in <folly/Padded.h>
template<class Container>
class Adaptor;Converts a sequence of Node into a sequence of its underlying elements (with enough functionality to make it useful, although it's not fully compatible with the STL container requirements, see below).
Provides iterators (of the same category as those of the underlying container), size(), front(), back(), push_back(), pop_back(), and const / non-const versions of operator[]the underlying container supports them). Does not provide push_front() / pop_front() or arbitrary insert / emplace / erase. Also provides reserve() / capacity() if supported by the underlying container.
Yes, it's called Adaptor, not Adapter, as that's the name used by the STL and by boost. Deal with it.
Internally, we hold a container of Node and the number of elements in the last block. We don't keep empty blocks, so the number of elements in the last block is always between 1 and Node::kElementCount (inclusive). (this is true if the container is empty as well to make push_back() simpler, see the implementation of the size() method for details).
| Name | Description |
|---|---|
Node | The underlying node type. |
const_iterator | Const element iterator. |
const_reference | Const reference to an element. |
difference_type | Signed difference type between iterators. |
iterator | Mutable element iterator. |
reference | Reference to an element. |
size_type | Unsigned size type. |
value_type | The underlying element type. |
| Name | Description |
|---|---|
Adaptor [constructor] | Constructors |
operator= | Assignment operators |
back | back overloads |
begin | begin overloads |
capacity | Returns the current element capacity. |
cbegin | Returns a const iterator to the first element. |
cend | Returns a const iterator past the last element. |
clear | Removes all elements. |
emplace_back | Constructs a new element in place at the end. |
empty | Reports whether the adaptor holds no elements. |
end | end overloads |
front | front overloads |
max_size | Returns the maximum number of elements the adaptor can hold. |
move | Return the underlying container and number of elements in the last block, and clear *this. Useful when you want to process the data as Nodes (again) and want to avoid copies. |
operator[] | Accesses the element at the given index. |
padToFullNode | Pads the last node up to a full node with a fill value. |
peek | Return a const reference to the underlying container and the current number of elements in the last block. |
pop_back | Removes the last element. |
push_back | Appends an element at the end. |
reserve | Reserves capacity for at least n elements. |
size | Returns the number of elements. |
swap | Swaps the contents of this adaptor with another. |
| Name | Description |
|---|---|
kElementsPerNode | The number of elements stored per node. |