Expr:                      Cont:
 {withcc k {+ 1 {k 2}}}      (lambda (x) x)
Expr                       Cont:
 {+ 1 {k 2}}                 (lambda (x) x)
   k = (lambda^ (x) x)
Expr                       Cont:
 1                           (lambda (x) {+ x {k 2}})
   k = (lambda^ (x) x)

Expr                       Cont:
 {k 2}                       (lambda (x) {+ 1 x})
   k = (lambda^ (x) x)
Expr:                      Cont:
 2                           (lambda (x) x)