Function isArrayLike

src/utils/array.ts:1–3

(items: Iterable<T> | ArrayLike<T>)

function isArrayLike<T>(items: Iterable<T> | ArrayLike<T>): items is ArrayLike<T> {
    return (items as ArrayLike<T>).length != null;
}

// NOTE: Iterating Array-like items using `for .. of` is 3x slower in Firefox
// https://jsben.ch/kidOp