{{alias}}( methods )
    Returns a fluent interface iterator constructor with a customized prototype
    based on provided methods.

    The methods argument should be an object which maps constructor method names
    to iterator functions.

    Each iterator function should have the following function signature:

      iterFcn( iterator, ...args )

    When a fluent interface iterator method is invoked, the method invokes the
    corresponding iterator function with an iterator and provided method
    arguments.

    If an iterator function returns an iterator, the corresponding fluent
    interface method returns a new fluent interface instance; otherwise, the
    corresponding fluent interface method returns the iterator function result.

    The iterator function evaluation context is always `null`.

    Iterator functions which return iterators are expected to return iterator
    protocol-compliant objects (i.e., an object having a `next` method which
    returns the next iterated value (if one exists) assigned to a `value`
    property and a `done` property having a boolean value indicating whether the
    iterator is finished).

    If an environment supports `Symbol.iterator`, the returned constructor
    returns iterators which are iterable.

    Parameters
    ----------
    methods: Object
        An object mapping method names to iterator functions.

    Returns
    -------
    FluentIterator: Function
        Fluent interface iterator constructor.

    Examples
    --------
    > var o = {};
    > o.head = {{alias:@stdlib/iter/head}};
    > o.some = {{alias:@stdlib/iter/some}};
    > var fiter = {{alias}}( o )


FluentIterator( iterator )
    Returns a new fluent interface iterator from a source iterator.

    Parameters
    ----------
    iterator: Object
        Source iterator.

    Returns
    -------
    iterator: Object
        Fluent interface iterator.

    Examples
    --------
    > var o = {};
    > o.head = {{alias:@stdlib/iter/head}};
    > o.some = {{alias:@stdlib/iter/some}};
    > var fiter = {{alias}}( o );
    > var it = fiter( {{alias:@stdlib/array/to-iterator}}( [ 0, 0, 1, 1, 1 ] ) );
    > var bool = it.head( 3 ).some( 2 )
    false


FluentIterator.prototype.next()
    Returns the next iterated value.

    Returns
    -------
    out: Object
        Iterator protocol-compliant object.

    out.value: any (optional)
        Next iterated value (if one exists).

    out.done: boolean
        Boolean flag indicating whether the iterator is finished.

    Examples
    --------
    > var o = {};
    > o.head = {{alias:@stdlib/iter/head}};
    > o.some = {{alias:@stdlib/iter/some}};
    > var fiter = {{alias}}( o );
    > var it1 = fiter( {{alias:@stdlib/array/to-iterator}}( [ 0, 0, 1, 1, 1 ] ) );
    > var it2 = it1.head( 3 );
    > var v = it2.next().value
    0
    > v = it2.next().value
    0
    > v = it2.next().value
    1


FluentIterator.prototype.return( [value] )
    Finishes an iterator and returns a provided value.

    Parameters
    ----------
    value: any (optional)
        Value to return.

    Returns
    -------
    out: Object
        Iterator protocol-compliant object.

    out.value: any (optional)
        Next iterated value (if one exists).

    out.done: boolean
        Boolean flag indicating whether the iterator is finished.

    Examples
    --------
    > var o = {};
    > o.head = {{alias:@stdlib/iter/head}};
    > o.some = {{alias:@stdlib/iter/some}};
    > var fiter = {{alias}}( o );
    > var it1 = fiter( {{alias:@stdlib/array/to-iterator}}( [ 0, 0, 1, 1, 1 ] ) );
    > var it2 = it1.head( 3 );
    > var v = it2.next().value
    0
    > var bool = it2.return().done
    true
    > v = it2.next().value
    undefined

    See Also
    --------