Node#

class Node(*args, **kwargs)#

The Node struct represents one node in a [n-ary tree][glib-N-ary-Trees].

Methods#

class Node
child_index(data: Any = None) → int#

Gets the position of the first child of a Node which contains the given data.

Parameters:

data – the data to find

child_position(child: Node) → int#

Gets the position of a Node with respect to its siblings. child must be a child of node. The first child is numbered 0, the second 1, and so on.

Parameters:

child – a child of node

children_foreach(flags: TraverseFlags, func: Callable[[Node, Any], None], data: Any = None) → None#

Calls a function for each of the children of a Node. Note that it doesn’t descend beneath the child nodes. func must not do anything that would modify the structure of the tree.

Parameters:

  • flags – which types of children are to be visited, one of ALL, LEAVES and NON_LEAVES

  • func – the function to call for each visited node

  • data – user data to pass to the function

depth() → int#

Gets the depth of a Node.

If node is None the depth is 0. The root node has a depth of 1. For the children of the root node the depth is 2. And so on.

destroy() → None#

Removes root and its children from the tree, freeing any memory allocated.

is_ancestor(descendant: Node) → bool#

Returns True if node is an ancestor of descendant. This is true if node is the parent of descendant, or if node is the grandparent of descendant etc.

Parameters:

descendant – a Node

max_height() → int#

Gets the maximum height of all branches beneath a Node. This is the maximum distance from the Node to all leaf nodes.

If root is None, 0 is returned. If root has no children, 1 is returned. If root has children, 2 is returned. And so on.

n_children() → int#

Gets the number of children of a Node.

n_nodes(flags: TraverseFlags) → int#

Gets the number of nodes in a tree.

Parameters:

flags – which types of children are to be counted, one of ALL, LEAVES and NON_LEAVES

classmethod pop_allocator() → None#
classmethod push_allocator() → None#
reverse_children() → None#

Reverses the order of the children of a Node. (It doesn’t change the order of the grandchildren.)

traverse(order: TraverseType, flags: TraverseFlags, max_depth: int, func: Callable[[Node, Any], bool], data: Any = None) → None#

Traverses a tree starting at the given root Node. It calls the given function for each node visited. The traversal can be halted at any point by returning True from func. func must not do anything that would modify the structure of the tree.

Parameters:

  • order – the order in which nodes are visited - IN_ORDER, PRE_ORDER, POST_ORDER, or LEVEL_ORDER.

  • flags – which types of children are to be visited, one of ALL, LEAVES and NON_LEAVES

  • max_depth – the maximum depth of the traversal. Nodes below this depth will not be visited. If max_depth is -1 all nodes in the tree are visited. If depth is 1, only the root is visited. If depth is 2, the root and its children are visited. And so on.

  • func – the function to call for each visited Node

  • data – user data to pass to the function

Unlinks a Node from a tree, resulting in two separate trees.

Returns:

0 if the name was successfully deleted, -1 if an error occurred

Fields#

class Node
children#
Points to the first child of the Node. The other

children are accessed by using the next pointer of each child.

data#

Contains the actual data of the node.

next#
Points to the node’s next sibling (a sibling is another

Node with the same parent).

parent#
Points to the parent of the Node, or is None if the

Node is the root of the tree.

prev#

Points to the node’s previous sibling.