[racket] Splicing `values' in-place

Two days ago, Laurent wrote:
> 
> I guess Scribble would be happy to use such splicing values.

It already does that with nested list structures.  (And IMO it's
cleaner to use lists as containers for random pacakging of values
rather than multiple values which is more natural for distinct roles
of the different values.)

-- 
          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                    http://barzilay.org/                   Maze is Life!