[Sbcl-devel] Fwd: Trace bug

[Nikodemus S. <nik...@ra...>]

---------- Forwarded message ----------
From: Leslie P. Polzer <sk...@vi...>
Date: 2009/5/12
Subject: Re: [Sbcl-devel] Trace bug
To: Nikodemus Siivola <nik...@ra...>

The following example program using CL-CONT reproduces one
aspect of the problem (different behaviour depending on
tracing) but not the encap crash:

(asdf:oos 'asdf:load-op :cl-cont)

(use-package :cl-cont)

(defun/cc do-something-else ()
 (let/cc k
   (if (y-or-n-p "back to the original plan?")
     (funcall k)
     (format t "alright, let's try something different."))))

(with-call/cc
 (do-something-else)
 (format t "alright, back on track~%"))


Demonstration:

CL-USER(9): (untrace)

T
CL-USER(10): (load "cont.lisp")

back to the original plan? (y or n) n
alright, let's try something different.
T
CL-USER(11): (trace do-something-else)

(DO-SOMETHING-ELSE)
CL-USER(12): (load "cont.lisp")
 0: (DO-SOMETHING-ELSE)

back to the original plan? (y or n) n
alright, let's try something different.  0: DO-SOMETHING-ELSE returned NIL
alright, back on track
T

I'm going to try to reproduce the crash as well.

 Leslie

--
http://www.linkedin.com/in/polzer