Remove elements from a referenced array during loop
key: 0; value: original.0
key: 1; value: original.1
key: 2; value: original.2

Remove elements from a referenced array during loop, using &$value
key: 0; value: original.0
key: 1; value: original.1

Add elements to a referenced array during loop
key: 0; value: original.0
key: 1; value: original.1
key: 2; value: original.2

Add elements to a referenced array during loop, using &$value
key: 0; value: original.0
key: 1; value: original.1
key: 2; value: original.2
key: 3; value: new.0
key: 4; value: new.1
key: 5; value: new.2
key: 6; value: new.3
Loop detected, as expected.