如何调整PHP星期数组起始日并保持原有顺序？

原数组：

$original = array("Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday");

目标数组（周日开头）：

array("Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday");

以下是几种可行的实现方法：

• 方法一：提取末尾元素后拼接
  取出原数组最后一个元素（周日），再和剩下的元素合并。如果不想修改原数组，先做一份拷贝：

  $original = array("Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday");
  $temp = $original;
  $sundayFirst = array_merge(array_pop($temp), $temp);
  

• 方法二：直接按索引构造新数组
  利用已知的数组索引位置，直接组合成目标数组，适合元素位置固定的场景：

  $original = array("Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday");
  $sundayFirst = array(
      $original[6],
      $original[0],
      $original[1],
      $original[2],
      $original[3],
      $original[4],
      $original[5]
  );
  

• 方法三：使用array_splice拆分合并
  用array_splice取出最后一个元素，再和原数组合并，这种方式不会改变原数组：

  $original = array("Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday");
  $sundayPart = array_splice($original, -1);
  $sundayFirst = array_merge($sundayPart, $original);
  

内容的提问来源于stack exchange，提问作者David