pp.scm

;; replからではなく、直接repl-printを使ったときに起きる。

;; Shiro Kawai's xrepl.pp (pp.scm line 70 ~ 86)
;; SourceForge.net Repository - [gauche] Contents of /Gauche-scripts/trunk/xrepl/xrepl/pp.scm
;; http://gauche.svn.sourceforge.net/viewvc/gauche/Gauche-scripts/trunk/xrepl/xrepl/pp.scm?revision=7388&view=markup

;; scan obj to find out shared structure and mark it in rp-dict.
(define (scan-shared obj level len)
  #?=(rp-dict) ; <--- ok
  (cond [(hash-table-get #?=(rp-dict) obj #f) ; <---- ok
         => (lambda (n)
              (unless (number? n)
                (hash-table-put! (rp-dict) obj
                                 (rlet1 n (rp-count) (rp-count (+ n 1))))))]
        [(or (> level *rp-level*) (> len *rp-length*) (simple-obj? obj))]
        [else
         (hash-table-put! #?=(rp-dict) obj #t) ; <---- !!! (rp-dict)==#f
         (cond [(pair? obj)
                (scan-shared (car obj) (+ level 1) 0)
                (scan-shared (cdr obj) level (+ len 1))]
               [(vector? obj)
                (do-ec (: i (min (vector-length obj) *rp-length*))
                       (scan-shared (vector-ref obj i) (+ level 1) 0))])]))

;;
#?="/home/shuji/gauche/xrepl/pp.scm":72:(rp-dict)
#?-    #<hash-table eq? 0x9f17528>
#?="/home/shuji/gauche/xrepl/pp.scm":73:(rp-dict)
#?-    #<hash-table eq? 0x9f17528>
#?="/home/shuji/gauche/xrepl/pp.scm":80:(rp-dict)
#?-    #f <------????
*** ERROR: hash table required, but got #f
Stack Trace:
_______________________________________
  0  (hash-table-put! (debug-print (rp-dict)) obj #t)
        At line 80 of "/home/shuji/gauche/xrepl/pp.scm"
  1  (scan-shared obj 0 0)
        At line 234 of "/home/shuji/gauche/xrepl/pp.scm"