sunterlib/scsh/interaction/inspect-exception.scm

52 lines
1.9 KiB
Scheme

;;; This file is part of the Scheme Untergrund Library.
;;; Copyright (c) 2002-2003 by Martin Gasbichler.
;;; For copyright information, see the file COPYING which comes with
;;; the distribution.
;; From SUnet plus one more call/cc to capture the continuation of the error
(define (with-fatal-and-capturing-error-handler handler thunk)
(call-with-current-continuation
(lambda (accept)
((call-with-current-continuation
(lambda (k)
(with-handler
(lambda (condition more)
(primitive-cwcc
(lambda (condition-continuation)
(if (error? condition)
(call-with-current-continuation
(lambda (decline)
(k (lambda ()
(handler condition condition-continuation decline))))))
(more)))) ; Keep looking for a handler.
(lambda () (call-with-values thunk accept)))))))))
(define (with-inspecting-handler port prepare thunk)
(with-fatal-and-capturing-error-handler
(lambda (condition condition-continuation more)
(with-handler
(lambda (c2 m2)
(more))
(if (prepare condition)
(let ((res
(remote-repl "Welcome to the command processor of the remote scsh"
condition-continuation
port)))
;; TODO: option to return to continuation of handler (by leaving out the with-continuation)
(with-continuation condition-continuation (lambda () res)))
(more))))
thunk))
(define display-preview (eval 'display-preview
(rt-structure->environment (reify-structure 'debugging))))
(define (display-continuation continuation . maybe-port)
(let ((out (if (null? maybe-port)
(current-output-port)
(car maybe-port))))
(if continuation
(display-preview (continuation-preview continuation)
out)
(display 'bottom-contination out))))