Hi all,
I'm trying to embed racket 3m version as interpreter into GUI application. For
custom interpreters this application have two required APIs - first one is init
and the second one is eval string. So in init I'm calling
scheme_register_tls_space and scheme_main_setup after. And in eval I'm using
custom version of Racket's read-eval-print-loop without recursion for
evaluation of thrings. And everything is working well until I've tried to
implement generator. Some reading of sources lead we into problem of
continuation. This simple code leads to error "continuation application:
attempt to cross a continuation barrier".
(define (generate-one-element-at-a-time lst)
(define (control-state return)
(for-each
(lambda (element)
(set! return (call-with-current-continuation
(lambda (resume-here)
;; Grab the current continuation
(set! control-state resume-here)
(return element)))))
lst)
(return 'you-fell-off-the-end))
(define (generator)
(call-with-current-continuation control-state))
;; Return the generator
generator)
(define generate-digit
(generate-one-element-at-a-time '(0 1 2)))
(generate-digit) ;; 0
(generate-digit) ;; 1 ;; error "continuation application: attempt to cross a
continuation barrier"
Attemt to use generators library lead to memory access violation. I suppose the
problem lies in stack frames which are cleared every time eval callback from
the main program is called. For some reasons I can't run racket in another
thread. So may be there is an option how this problem could be solved? May be
my assumption is not right? May be switch to CGC and mapping stack with
scheme_set_stack_base into heap can help? If it help I can show the source of
this plugin.
Thanks,
Kirill
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