use function Pairs\cons;
use function Pairs\car;
use function Pairs\cdr;
use function Pairs\toString;
use function Lists\length;
use function Lists\reverse;
use function Lists\map;
use function Lists\filter;
use function Lists\reduce;
$pair = cons(1, 2);
$one = Pairs\car($pair); // $one = 1;
$two = Pairs\cdr($pair) // $two = 2;
$list = cons(1, cons(2, cons(3, cons(4, cons(5, cons(6, null))))));
$length = length($list); // $length = 6;
$filter = filter(function ($x) {
return $x % 2 == 0;
}, $list);
$result = toString($filter); \\ $result = "(2, 4, 6)";