Gee's iterators are "on-track" iterators. They always point to an item except before the first call to
next, or, when an item has been removed, until the next call to
Please note that when the iterator is out of track, neither get nor
remove are defined and both might fail. After the next call to
next, they will be defined again.
Please also note that, unless specified otherwise, iterators before iteration started should behave as if after deletion of the first element.
Whenever documentation states about the iterator 'out of track', 'invalid' or 'in-between elements' this refers to the same concept.