Re: [Chicken-users] Printing procedures returned from call/cc

[Peter Bex]

On Tue, Jul 31, 2012 at 03:24:16PM +0200, Thomas Chust wrote:
> On Tue, 31 Jul 2012, Jeronimo Pellegrini wrote:
> >I was wondering why this happens in Chicken (recent checkout from git):
> >
> >(let ((lst (call/cc (lambda (x)
> >                     (print 'something)
> >                     (call/cc (lambda (y)
> >                                (list x y)))))))
> > (print lst)
> > (print (eq? (car lst) (cadr lst)))
> > (print (eqv? (car lst) (cadr lst)))
> 
> this is really strange!
> 
> Since the second lambda expression is in tail position with respect to the
> first, the two continuations x and y are actually equivalent, so at first
> I was less surprised by their printed representation than by the results
> of the equality predicates.

Same here.  I think what we're seeing here is the same procedure but
different closure objects (one has access to 'x', the other to 'y').
Only the procedure name is printed.

Cheers,
Peter
-- 
http://sjamaan.ath.cx
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