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Coding Standards
boost::intrusive::circular_list_algorithms
// In header: <boost/intrusive/circular_list_algorithms.hpp> template<typename NodeTraits> class circular_list_algorithms { public: // types typedef NodeTraits::node node; typedef NodeTraits::node_ptr node_ptr; typedef NodeTraits::const_node_ptr const_node_ptr; typedef NodeTraits node_traits; // member classes/structs/unions struct stable_partition_info { // public data members std::size_t num_1st_partition; std::size_t num_2nd_partition; node_ptr beg_2st_partition; }; // public static functions static void init(const node_ptr &); static bool inited(const const_node_ptr &); static void init_header(const node_ptr &); static bool unique(const const_node_ptr &); static std::size_t count(const const_node_ptr &); static node_ptr unlink(const node_ptr &); static void unlink(const node_ptr &, const node_ptr &); static void link_before(const node_ptr &, const node_ptr &); static void link_after(const node_ptr &, const node_ptr &); static void swap_nodes(const node_ptr &, const node_ptr &); static void transfer(const node_ptr &, const node_ptr &, const node_ptr &); static void transfer(const node_ptr &, const node_ptr &); static void reverse(const node_ptr &); static void move_backwards(const node_ptr &, std::size_t); static void move_forward(const node_ptr &, std::size_t); static std::size_t distance(const const_node_ptr &, const const_node_ptr &); template<typename Pred> static void stable_partition(node_ptr, const node_ptr &, Pred, stable_partition_info &); // private static functions static void swap_prev(const node_ptr &, const node_ptr &); static void swap_next(const node_ptr &, const node_ptr &); };
circular_list_algorithms provides basic algorithms to manipulate nodes forming a circular doubly linked list. An empty circular list is formed by a node whose pointers point to itself.
circular_list_algorithms is configured with a NodeTraits class, which encapsulates the information about the node to be manipulated. NodeTraits must support the following interface:
Typedefs:
node
: The type of the node that forms the circular list
node_ptr
: A pointer to a node
const_node_ptr
: A pointer to a const node
Static functions:
static node_ptr get_previous(const_node_ptr n);
static void set_previous(node_ptr n, node_ptr prev);
static node_ptr get_next(const_node_ptr n);
static void set_next(node_ptr n, node_ptr next);
circular_list_algorithms
public static functionsstatic void init(const node_ptr & this_node);
Effects: Constructs an non-used list element, so that inited(this_node) == true
Complexity: Constant
Throws: Nothing.
static bool inited(const const_node_ptr & this_node);
Effects: Returns true is "this_node" is in a non-used state as if it was initialized by the "init" function.
Complexity: Constant
Throws: Nothing.
static void init_header(const node_ptr & this_node);
Effects: Constructs an empty list, making this_node the only node of the circular list: NodeTraits::get_next(this_node) == NodeTraits::get_previous(this_node) == this_node
.
Complexity: Constant
Throws: Nothing.
static bool unique(const const_node_ptr & this_node);
Requires: this_node must be in a circular list or be an empty circular list.
Effects: Returns true is "this_node" is the only node of a circular list: return NodeTraits::get_next(this_node) == this_node
Complexity: Constant
Throws: Nothing.
static std::size_t count(const const_node_ptr & this_node);
Requires: this_node must be in a circular list or be an empty circular list.
Effects: Returns the number of nodes in a circular list. If the circular list is empty, returns 1.
Complexity: Linear
Throws: Nothing.
static node_ptr unlink(const node_ptr & this_node);
Requires: this_node must be in a circular list or be an empty circular list.
Effects: Unlinks the node from the circular list.
Complexity: Constant
Throws: Nothing.
static void unlink(const node_ptr & b, const node_ptr & e);
Requires: b and e must be nodes of the same circular list or an empty range.
Effects: Unlinks the node [b, e) from the circular list.
Complexity: Constant
Throws: Nothing.
static void link_before(const node_ptr & nxt_node, const node_ptr & this_node);
Requires: nxt_node must be a node of a circular list.
Effects: Links this_node before nxt_node in the circular list.
Complexity: Constant
Throws: Nothing.
static void link_after(const node_ptr & prev_node, const node_ptr & this_node);
Requires: prev_node must be a node of a circular list.
Effects: Links this_node after prev_node in the circular list.
Complexity: Constant
Throws: Nothing.
static void swap_nodes(const node_ptr & this_node, const node_ptr & other_node);
Requires: this_node and other_node must be nodes inserted in circular lists or be empty circular lists.
Effects: Swaps the position of the nodes: this_node is inserted in other_nodes position in the second circular list and the other_node is inserted in this_node's position in the first circular list.
Complexity: Constant
Throws: Nothing.
static void transfer(const node_ptr & p, const node_ptr & b, const node_ptr & e);
Requires: b and e must be nodes of the same circular list or an empty range. and p must be a node of a different circular list or may not be an iterator in Effects: Removes the nodes from [b, e) range from their circular list and inserts them before p in p's circular list.
Complexity: Constant
Throws: Nothing.
static void transfer(const node_ptr & p, const node_ptr & i);
Requires: i must a node of a circular list and p must be a node of a different circular list.
Effects: Removes the node i from its circular list and inserts it before p in p's circular list. If p == i or p == NodeTraits::get_next(i), this function is a null operation.
Complexity: Constant
Throws: Nothing.
static void reverse(const node_ptr & p);
Effects: Reverses the order of elements in the list.
Throws: Nothing.
Complexity: This function is linear time.
static void move_backwards(const node_ptr & p, std::size_t n);
Effects: Moves the node p n positions towards the end of the list.
Throws: Nothing.
Complexity: Linear to the number of moved positions.
static void move_forward(const node_ptr & p, std::size_t n);
Effects: Moves the node p n positions towards the beginning of the list.
Throws: Nothing.
Complexity: Linear to the number of moved positions.
static std::size_t distance(const const_node_ptr & f, const const_node_ptr & l);
Requires: f and l must be in a circular list.
Effects: Returns the number of nodes in the range [f, l).
Complexity: Linear
Throws: Nothing.
template<typename Pred> static void stable_partition(node_ptr beg, const node_ptr & end, Pred pred, stable_partition_info & info);