Infinite lists

Laziness enables "infinite lists"

Recall the Range generator from before:

> my $r = 100..200;
> say $r.reify(5).perl;
(100, 101, 102, 103, 104, 105..200)

> my $r = 100..Inf;
> say $r.reify(5).perl;
(100, 101, 102, 103, 104, 105..Inf)

> say (105..Inf).reify(3)