sunet/scheme/httpd/surflets/handle-fatal.scm

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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Error-Handler
;;
;; Adopted from WITH-FATAL-ERROR-HANDLER, but handles everything that
;; is catchable. We must catch everything because we also want
;; exceptions (and warnings) to be catched (e.g. when the surflet is
;; loaded.)
(define (with-fatal-handler* handler thunk)
(call-with-current-continuation
(lambda (accept)
((call-with-current-continuation
(lambda (k)
(with-handler (lambda (condition more)
(call-with-current-continuation
(lambda (decline)
(k (lambda () (handler condition decline)))))
(more)) ; Keep looking for a handler.
(lambda () (call-with-values thunk accept)))))))))
(define-syntax with-fatal-handler
(syntax-rules ()
((with-fatal-handler handler body ...)
(with-fatal-handler* handler
(lambda () body ...)))))