constructor(url, base) {
		url = new URL(url, base);
		super(url);

		if (DEV) {
			tag(this.#protocol, 'SvelteURL.protocol');
			tag(this.#username, 'SvelteURL.username');
			tag(this.#password, 'SvelteURL.password');
			tag(this.#hostname, 'SvelteURL.hostname');
			tag(this.#port, 'SvelteURL.port');
			tag(this.#pathname, 'SvelteURL.pathname');
			tag(this.#hash, 'SvelteURL.hash');
			tag(this.#search, 'SvelteURL.search');
		}

		current_url = this;
		this.#searchParams = new SvelteURLSearchParams(url.searchParams);
		current_url = null;
	}
@param {string | URL} url
@param {string | URL} [base]