That's why I moved from Scheme to Common Lisp, it's nice being able to do... (defstruct Task (future :type Future) (task-sender :type Sender)) And h

That's why I moved from Scheme to Common Lisp, it's nice being able to do... (defstruct Task (future :type Future) (task-sender :type Sender)) And have SBCL warn me when I try to jam the wrong type in.