Question

In regard to my question here, Jacob Relkin suggested a great solution of using call_user_func_array. That solved my problem but now I am really curious on how to do this in the absence of this function to achieve what I wanted in my original question which is below for reference:

Original Question:

I am creating an array of arrays in the following way:

$final_array = array();
for($i = 0; $i < count($elements); $i++) {
    for($j = 0; $j < count($elements); $j++) {
        if($i!=$j)
            $final_array[] = array_intersect($elements[$i], $elements[$j]);
    }
}

I am trying to find out the list of elements that occur in all the arrays inside the $final_array variable. So I was wondering how to pass this to array_intersect function. Can someone tell me how to construct args using $final_array[0], $final_array[1], ... $final_array[end_value] for array_intersect? Or if there is a better approach for this, that would be great too.

I am looking for a way to construct the following:

array_intersect($final_array[0], $final_array[1], $final_array[2], ...)

Answer 1

Well, the only real way to do this other than call_user_func_array would be to implode the resulting array into comma-separated arguments, then do something really really evil and use eval:

$args_imploded = implode(',', $some_array);

$result = eval('return array_intersect(' . $args_imploded . ')');