Re: [Chicken-janitors] #1127: dynamic wind in its own thread

[Chicken Trac]

#1127: dynamic wind in its own thread
-------------------------+--------------------------------------------------
  Reporter:  kristianlm  |       Owner:         
      Type:  defect      |      Status:  new    
  Priority:  major       |   Milestone:  someday
 Component:  unknown     |     Version:  4.9.x  
Resolution:              |    Keywords:         
-------------------------+--------------------------------------------------

Comment(by kristianlm):

 Meanwhile, here's a workaround:

 {{{
 (use srfi-18 test)
 ;; define address@hidden once
 (define original#thread-start!
   (handle-exceptions e thread-start!
                      original#thread-start!))

 (define (##dbg#thread-thunk thread)
   (##sys#slot thread 1))

 (define (thread-start! thread)

   ;; original thunk
   (define original-thunk
     (if (thread? thread)
         (##dbg#thread-thunk thread)
         thread))

   ;; simply wrap original thunk inside a handle-exceptions with
   ;; re-raises any errors seem to do the trick
   (define (thunk)
     (handle-exceptions e (raise e)
                        (original-thunk)))

   (original#thread-start!
    (if (thread? thread)
        (make-thread thunk (thread-name thread))
        (make-thread thunk))))


 (test-group
  "dynamic-wind.workaround"

  (define ran? #f)
  (define (trick)
    (dynamic-wind (lambda () (void))
                  (lambda () (error 'x))
                  (lambda () (set! ran? #t))))

  ;; throw away warnings
  (parameterize ((current-error-port (open-output-string)))
    (test-error
     (thread-join!
      (thread-start!
       (lambda () (trick))))))

  (test #t ran?))

 }}}

 This test-group passes, but fails if you don't redefine {{{thread-
 start!}}}.

-- 
Ticket URL: <http://bugs.call-cc.org/ticket/1127#comment:1>
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CHICKEN Scheme is a compiler for the Scheme programming language.