[racket] A primitive more fundamental than a continuation?

>>What you can NOT do even in this world is visit the past and perform a
different computation than (+ 1 2).

Yes. I agree that Racket's  eval order combined with which branch the
continuation is reified on uniquely determines which branches are in the
past and which are in the future.

I acknowledge this relation between eval order and branch-position is
critical to understanding behavior of an invoked continuation. Branches in
the past are values, branches in the future still must be eval'd after
invocation of the continuation.

Let me now read your paper and think about what you've written here. I may
have more questions later.

Thanks very much for the answer.

R./

Zack