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How to get “Element” -type value from “Element.parentNode” instead of “Node & ParentNode”?

The recipe of event delegating from http://youmightnotneedjquery.com/:

document.addEventListener(eventName, function(e) {
    // loop parent nodes from the target to the delegation node
    for (var target = e.target; target && target != this; target = target.parentNode) {
        if (target.matches(elementSelector)) {
            handler.call(target, e);
            break;
        }
    }
}, false);

I am trying rewrite it to TypeScript type-safely (for click event for now):

export default function delegateClickEventHandling(
    {
      clickTargetSelector,
      container = document
    }: {
      clickTargetSelector: string;
      container: HTMLElement | Document;
    },
    handler: (event: MouseEvent) => void
): void {

  container.addEventListener("click", (event: Event): void => {

    if (!(event instanceof MouseEvent)) {
      return;
    }

    for (
        let targetParentNode: Element | null = event.target as Element;
        isNotNull(targetParentNode) && targetParentNode !== event.currentTarget;
        targetParentNode = targetParentNode.parentNode
    ) {

      if (targetParentNode.matches(clickTargetSelector)) {
        handler(event);
      }
    }
  }, false);
}

TypeScript compiler tells me:

TS2322: Type '(Node & ParentNode) | null' is not assignable to type 'Element | null'.
Type 'Node & ParentNode' is not assignable to type 'Element | null'.
Type 'Node & ParentNode' is missing the following properties from type 'Element':
 assignedSlot, attributes, classList, className, and 64 more.

The .matches() is the method of the Element – I can’t to call it from Node & ParentNode). What have I do?

If targetParentNode = targetParentNode.parentNode as Element is completely all right please explain why.

P. S. Please note that any, object and type annotation omitting are not allowed.

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Answer

You just need to cast targetParentNode.parentNode to Element.

So for loop might be look like this:

for (
    let targetParentNode: Element = event.target as Element;
    targetParentNode !== event.currentTarget;
    targetParentNode = targetParentNode.parentNode as Element
) {

  if (targetParentNode.matches(clickTargetSelector)) {
    handler(event);
  }
}

PlaygrounLink

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