/**
 * Determines whether an element is a void element as defined by the HTML specification.
 * Void elements cannot have any contents (e.g., `<br>`, `<img>`, `<input>`).
 *
 * @see https://html.spec.whatwg.org/multipage/syntax.html#void-elements
 *
 * @param el - An object with a `localName` property representing the element's tag name
 * @returns `true` if the element is a void element
 */
export declare function isVoidElement(el: {
    readonly localName: string;
}): boolean;