Re: [Gcl-devel] compute-restarts

[Camm Maguire]

Greetings!  And thanks again Peter for looking into this.

Paul, I think that Peter is right here, and you want handler-bind
instead of handler-case.  If you agree, could you please adjust the
tests, and I'll back out of the 'fix' I made in restart.lisp.

Take care,

Peter Wood <address@hidden> writes:

> On Tue, Oct 15, 2002 at 01:08:59PM -0400, Camm Maguire wrote:
> 
> > >    (handler-case
> >     (make-package "A")
> >       (error (c)(format t "restart-clusters is ~S~%" 
> > conditions::*restart-clusters*)
> >       (if (position 'abort (compute-restarts c)
> >                     :key #'restart-name :test-not #'eq)
> >           'success
> >         'failure)))
> > 
> > in signal, restart clusters is ((#<RESTART.1>))
> > restart-clusters is NIL
> > FAILURE
> > 
> > =============================================================================
> > When handler-case defines the new error processing lambda function, it
> > is appearing to carry with it the current *restart-clusters* as
> > opposed to the dynamically bound value at invocation time.  Or
> > something similar.  What I'd like to know is if this is the correct
> > lexical binding behavior, i.e. whether the bug is in handler.lisp, or
> > in the lexical binding.  If the former, it would seem rather difficult
> > to know in LISP which variables need exporting in this manner amd in
> > which circumstances.
> > 
> > Take care,
> > 
> > 
> 
> Hi again,
> 
> Is this what you are looking for?
> 
> (defun pack-test (X)
>   (handler-bind  ((error #'(lambda (c)
>                            (if (position 'abort (compute-restarts c)
>                                          :key #'restart-name :test-not #'eq)
>                                (progn (format t "(compute-restarts) => 
> ~S~%*handler-clusters* => ~S~%"
>                                               (compute-restarts) 
> conditions::*handler-clusters*)
>                                       (invoke-restart (find-restart 'abort)))
>                              (progn (format t "FAILURE~%")
>                                     (invoke-restart (find-restart 
> 'abort)))))))
>     (make-package X)))
> 
> (pack-test "X") ;;=> #<"X" PACKAGE>
> (pack-test "X") ;;=>
> 
> in signal, restart clusters is ((#<RESTART.2>))
> (compute-restarts) => (#<RESTART.2>
>                        #<RESTART.0>)
> *handler-clusters* => NIL
> 
> Top level.
> >
> 
> Regards,
> Peter
> 
> 

-- 
Camm Maguire                                            address@hidden
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"The earth is but one country, and mankind its citizens."  --  Baha'u'llah