array(4) {
  [0]=>
  string(4) "eins"
  [1]=>
  string(4) "zwei"
  [2]=>
  string(4) "drei"
  [3]=>
  string(4) "vier"
}
<br />Index is at: eins<hr />0: Currently at element eins<br />1: Currently at element zwei - unsetting. Now we have drei<br />2: Currently at element drei<br />3: Currently at element vier<br /><hr />array(3) {
  [0]=>
  string(4) "eins"
  [2]=>
  string(4) "drei"
  [3]=>
  string(4) "vier"
}
<hr />0: Currently at element eins<br />1: Currently at element drei<br />2: Currently at element vier<br />