{{alias}}( iter0, ...iterator )
    Returns an iterator which returns the union of two or more iterators.

    Value "uniqueness" is determined according to strict equality.

    A returned iterator internally buffers unique values and, thus, has O(N)
    memory requirements, where `N` is the total number of source iterator
    values.

    If an environment supports Symbol.iterator and all provided iterators are
    iterable, the returned iterator is iterable.

    Parameters
    ----------
    iter0: Object
        Input iterator.

    iterator: ...Object
        Input iterators.

    Returns
    -------
    iterator: Object
        Iterator.

    iterator.next(): Function
        Returns an iterator protocol-compliant object containing the next
        iterated value (if one exists) and a boolean flag indicating whether the
        iterator is finished.

    iterator.return( [value] ): Function
        Finishes an iterator and returns a provided value.

    Examples
    --------
    > var it1 = {{alias:@stdlib/array/to-iterator}}( [ 1, 2, 1, 2, 4 ] );
    > var it2 = {{alias:@stdlib/array/to-iterator}}( [ 1, 2, 5, 2, 3 ] );
    > var it = {{alias}}( it1, it2 );
    > var v = it.next().value
    1
    > v = it.next().value
    2
    > v = it.next().value
    4
    > v = it.next().value
    5
    > v = it.next().value
    3
    > var bool = it.next().done
    true

    See Also
    --------