Re: Tk 4 bindings and Scheme

From: Andrew Dorrell <andrewd_at_ee.uts.edu.au>
Date: Wed, 29 Nov 95 10:20:53 EST

Erik,

> In Tcl, if you want to short-circuit the multiple bindings, you can have
> the binding that gets run first use a `break' statement. This will not
> only exit from the script it's running, but also stop Tk from running
> the rest of the bindings it finds for the event. However, Scheme (and
> therefore STk) has no `break' statement.
>
> Has anyone else had this problem? Is there a good way to deal with it?

        I have not adressed this problem myself as I am still using STk-2.2
but I would like to suggest that scheme does include a more flexible exit
mechanism for `breaking': call-with-current-continuation (call/cc).
If there is a "clean scheme" solution to your problem (as I would hope there
would be) it would probably use this mechanism.

Sorry I can't be of greater assistance...

Regards,

-- 
------------------------------------------------------------------------------
Mr Andrew Dorrell
School of Electrical Engineering                 *
University of Technology, Sydney                     *
PO Box 123                                     *
Broadway NSW 2007                                   .  
AUSTRALIA
                                                    *       /---\  Whoo?
Phone:   61 2 330 2395                                      (o o) /
Fax:     61 2 330 2435                                      ( : )  
email:   andrewd_at_ee.uts.edu.au                               ^ ^     
    OR   dorrell_at_ihf.uts.edu.au
------------------------------------------------------------------------------

Received on Wed Nov 29 1995 - 09:52:21 CET