数组数组上的Array_Filter / Array_Unique？

Question

I want to perform the following action on an array of arrays:

$fix = array($array1, $array2, $array3, $array4);

foreach ($fix as &$f){
    $f = array_filter(array_unique($f));
}

Unfortunately, despite my efforts to pass each array by reference, I'm not getting filtered and uniquified results at the end of the process. Is there a simple way to get this done? Or should I approach this problem in a different way? I can just call the filtering etc on each array in turn, which works, but it seems like that can't be the DRY way to go...

Answer 1

$fix = array($array1, $array2, $array3, $array4);

foreach ($fix as $k => $v){
    $fix[$k] = array_filter(array_unique($v));
}

---

Based on comments, a way to change the original variables:

$fix = compact($array1, $array2, $array3, $array4);
foreach ($fix as $k => $v){
    $fix[$k] = array_filter(array_unique($v));
}
extract($fix);