/**
 * A generator function that iterates over an array and yields the result of applying a callback function to each item
 * with additional metadata about the iteration.
 *
 * @param items - The array to iterate over
 *
 * @param f - The callback function to apply to each item
 * @param f.value - The current item being processed
 * @param f.options - Additional information about the current iteration
 * @param f.options.index - The index of the current item
 * @param f.options.first - Whether the current item is the first in the array
 * @param f.options.last - Whether the current item is the last in the array
 * @param f.options.odd - Whether the current index is odd
 * @param f.options.even - Whether the current index is even
 *
 * @example
 * ```ts
 * render() {
 *   return html`
 *     <ul>
 *       ${loop(
 *         this.items,
 *         (item, { odd }) => html`<li class="${odd ? 'odd' : 'even'}">${item}</li>`,
 *       )}
 *     </ul>
 *   `;
 * }
 * ```
 */
export declare function loop<T>(items: T[] | undefined, f: (value: T, options: {
    index: number;
    first: boolean;
    last: boolean;
    odd: boolean;
    even: boolean;
}) => unknown): Generator<unknown, void, unknown>;