$elementindex 0 is foo.txt $elementindex 1 is bar.txt $elementindex 2 is blivitz.txt After revisions, $elementindex 0 is foo.txt After revisions, $elementindex 1 is new element After revisions, $elementindex 2 is bar.txt After revisions, $elementindex 3 is blivitz.txt now $elementindex 0 is foo.txt now $elementindex 1 is addelement.txt now $elementindex 2 is bar.txt now $elementindex 3 is blivitz.txt