Array_splice function result Assignment solution idea

Array_splice function Result Assignment
$arr 1 = Array (All-in-all);
$arr 2 = array (3,4,5);
$arr 1 = array_splice ($arr 2,1,1);
Print_r ($arr 1);


The result is an array ([0] = 4)
In a logical sense, the assignment operator does not take place until the Array_splice function is finally completed.
Then Array_splice ($arr 2,1,1) Gets the value within the array $arr2 should be (3,4),
Then the operation "=", then get the contents of the $ARR1 array should be (3,4), but actually run the entire
$arr 1 = array_splice ($arr 2,1,1), but the contents of the $ARR1 array are (4), solved.
------to solve the idea----------------------
The number in the handbook is clear: Returns an array containing the removed cells
Array_splice ($arr 2,1,1) is equivalent to Array_slice ($arr 2,1,1) only from the returned results
But the former has changed the original state of $arr 2.

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