(PHP 4, PHP 5, PHP 7)
array_shift — Shift an element off the beginning of array
   array_shift() shifts the first value of the
   array off and returns it, shortening the
   array by one element and moving everything
   down. All numerical array keys will be modified to start counting from zero
   while literal keys won't be touched.
  
Note: This function will reset() the array pointer of the input array after use.
arrayThe input array.
   Returns the shifted value, or NULL if array is
   empty or is not an array.
  
Example #1 array_shift() example
<?php
$stack = array("orange", "banana", "apple", "raspberry");
$fruit = array_shift($stack);
print_r($stack);
?>
The above example will output:
Array
(
    [0] => banana
    [1] => apple
    [2] => raspberry
)
and orange will be assigned to $fruit.