PHP: 'rotate' an array?

Question

is it possible to easily \'rotate\' an array in PHP ?

Like this: 1, 2, 3, 4 -> 2, 3 ,4 ,1

Is there some kind of built-in PHP function for this?

Answer 1

Here's a function to rotate an array (zero-indexed array) to any position you want:

function rotateArray($inputArray, $rotateIndex) {
  if(isset($inputArray[$rotateIndex])) {
    $startSlice = array_slice($inputArray, 0, $rotateIndex);
    $endSlice = array_slice($inputArray, $rotateIndex);
    return array_merge($endSlice, $startSlice);
  }
  return $inputArray;
}

$testArray = [1,2,3,4,5,6];
$testRotates = [3, 5, 0, 101, -5];

foreach($testRotates as $rotateIndex) {
  print_r(rotateArray($testArray, $rotateIndex));
}