Include multiple times in a row 'interrupts' definitions

[Diego]

Given file include.scm:

(define (foo)
  (print that))

and a file "include2.scm" with arbitrary contents (including an empty file), the following code works (interpreted and compiled):

#!/usr/bin/csi -ss
(define (main #!optional args)
  (include "include.scm")
  (define that "hey")
  (foo))

(main)

whereas this does not (interpreted or compiled):

#!/usr/bin/csi -s
(define (main #!optional args)
  (include "include.scm")
  (include "include2.scm")
  (define that "hey")
  (foo))

(main)

The latter throws an error about that being unbound.