An iterator for enumerating an index on every item.
Abstraction of types implementing RefValueIter into an iter
object.
An iterator, running on a specific object using an index, yielding items that are
returned by a specific method call with the index. The index is calculated with a
given unary operation (by default, iinc and idec)
An iterator, running on a specific object using an index, yielding items that are
returned by a specific method call with the index. The index is calculated with a
given unary operation (by default, iinc and idec)