Function indexOfNode

packages/react-aria/src/tokenfield/useTokenField.ts:597–605

(node: Node)

}

function indexOfNode(node: Node) {
  let index = 0;
  let n: Node | null = node;

  while ((n = n.previousSibling)) {
    index++;
  }
  return index;
}

export function getSelection(container: Element): [Position, Position] | null {
  let selection = window.getSelection();