PHP array_merge if not empty

Question

Trying to merge 4 arrays, but some may be empty at certain times.

$array_1 = array('something1', something2);
$array_2 = array('something3', something4);
$array_3 = array();
$array_4 = array('something1', something2);

$list = array_merge($array_1,$array_2,$array_3,$array_4);

print_r($list);

But if one of the arrays are empty, there will be an error. I've been googling forever, but I can't find a solid simple answer on how to check for empty arrays before merging.

Argument #2 is not an array

Or whichever array is empty is the argument number. How do I strip out empty arrays before merging?

Answer 1

There is NO error with an empty array. There is only an error if the arg is NOT an array.

You could check is_array() or:

$list = array_merge(
(array)$array_1,
(array)$array_2,
(array)$array_3,
(array)$array_4
);