//#region src/iterator/head.d.ts /** * Returns the first element produced by `source`, or `undefined` if it is empty. * This pulls a single element and then stops, so it is safe to use on an * infinite iterator. * * This consumes the iterator rather than peeking at it: after reading the first * element, `source` is closed via its `return` method (matching the native * `Iterator.prototype.find`), so it cannot be iterated further. * * @template T - The type of elements produced by the iterator. * @param source - The iterator to read the first element from. * @returns The first element, or `undefined` when the iterator yields nothing. * * @example * head([1, 2, 3].values()); // => 1 * head([].values()); // => undefined */ declare function head(source: Iterator): T | undefined; //#endregion export { head };