A type that represents all the possible sources that can be used to create an ExtraIterator.
Type Parameters
T
The type of the values yielded by the iterator; or the type of the elements of the array or array-like
object.
Remarks
This includes any object that is either an Iterator, an Iterable, or an "array-like" object (i.e., an object that
has a length property that is a number and numerically indexed elements).
A type that represents all the possible sources that can be used to create an
ExtraIterator.