iterable-tree

Implements an iterable tree with associated helpers.

Install with npm

$ npm i @koaninc/iterable-tree

Creating a tree

A tree consists of Nodes with a unique id field and an (optional) parentId reference.

const Tree = require('@koaninc/iterable-tree');

const tree = Tree.from([
  { id: 'root' },
  { id: 'child-a', parentId: 'root' },

  // Multiple root (parent-less) nodes are supported
  { id: 'root-2' },
]);

Iteration

Iterate over the tree's nodes as if it were a Map:

const ids = [];

for (const [nodeId, node] of tree) {
  ids.push(node.id.toUpperCase());
}

console.log(ids); // ['ROOT', 'CHILD-A']

Helpers

.add(node)

Adds a new element to the tree

.without(ancestorNodeId)

Returns a copy of the tree with the node and any descendants removed

.descendantsOf(ancestorNodeId)

Returns an array containing the specified ancestor's descendants

.isAncestorOf(nodeId, ancestorId)

Returns true if the node is descended from the specified ancestor

.ancestorsOf(nodeId)

Returns all ancestors of the specified node

.roots()

Returns an array containing all "root" nodes

.flat()

Projects the tree into an array

License

ISC