Brief example about binary trees made in typescript

binary_tree.ts

const useState = <A>(a: any): any => { };

type Tree = [number, Tree, Tree] | null

type UUID = string;

type Edge = { from: UUID, to: UUID }
type NNode = { nodes: NNode[], id: UUID, label: string }

const [nodes, setNodes] = useState<NNode | null>(null);

const root: NNode = {
    id: 'uuid 1',
    label: 'john doe',
    nodes: [

    ],
};

setNodes(root);

const addNewNodes = (nodes: NNode[], id: string, newNodes: NNode[]): NNode[] => {
    const target = nodes.find(node => node.id === id);

    if(!target)
        return nodes.map(children => (
            {...children, nodes: addNewNodes(children.nodes, id, newNodes)}
        ));

    return [
        ...nodes.filter(node => node.id === id),
        {
            ...target,
            nodes: newNodes
        }
    ];
};

const id: string = 'uuid 1';
let newNodes: NNode[];

setNodes(state => addNewNodes(state.nodes, id, newNodes))

const y1: Tree = [5, null, null]
const y: Tree = [4, y1, null]
const x1: Tree = [3, null, null]
const x: Tree = [2, x1, null]
const t: Tree = [1, x, y]

const navigate = (tree: Tree, mov: (1 | 0)[]): Tree => {
    if (tree === null) return null;

    if (mov.length === 0) return tree;

    const [i, ...rest] = mov;

    if (i === 1)
        return navigate(tree[1], rest);

    return navigate(tree[2], rest)
};

console.log(navigate(t, [0]))