public function concat($array1, $array2, $array_ = null): array
    {
        $arguments = func_get_args();
        foreach ($arguments as &$argument) {
            if (!is_array($argument)) {
                $argument = [$argument];
            }
        }
        return call_user_func_array('array_merge', $arguments);
    }
public function concat($array1, $array2, $array_ = null): array
    {
        $arguments = func_get_args();
        foreach ($arguments as &$argument) {
            if (!is_array($argument)) {
                $argument = [$argument];
            }
        }
        return call_user_func_array('array_merge', $arguments);
    }
public function concat ( $ array1 , $ array2 , $ array_ = null ) : array { $ arguments = func_get_args ( ) ; foreach ( $ arguments as & $ argument ) { if ( ! is_array ( $ argument ) ) { $ argument = [ $ argument ] ; } } return call_user_func_array ( 'array_merge' , $ arguments ) ; }
Concatenate arrays or values to a new array

@param array|mixed $array1 First array or value
@param array|mixed $array2 Second array or value
@param array|mixed $array_ Optional variable list of additional arrays / values
@return array The array with concatenated arrays or values
Concatenate arrays or values to a new array