Function walkTree

packages/markmap-common/src/util.ts:14–25

(
  tree: T,
  callback: (item: T, next: () => U[] | undefined, parent?: T) => U,
)

}

export function walkTree<T extends { children?: T[] }, U = void>(
  tree: T,
  callback: (item: T, next: () => U[] | undefined, parent?: T) => U,
): U {
  const walk = (item: T, parent?: T): U =>
    callback(
      item,
      () => item.children?.map((child: T) => walk(child, item)),
      parent,
    );
  return walk(tree);
}

export function addClass(className: string, ...rest: string[]): string {
  const classList = (className || '').split(' ').filter(Boolean);