Re: :PROPAGATED and :PROPAGATE-TO in STklos slot descriptions

From: Andrew Dorrell <andrewd_at_mountains.net.au>
Date: Thu, 26 Mar 1998 10:56:39 +1100

Paolo Amoroso wrote:
>
> What are the :PROPAGATED and :PROPAGATE-TO keywords used for in STklos slot
> descriptions?

propagated and propagate-to provide a simple mechanism for composite
widgets to inherit and possibly rename the slots of the tk widgets
from which they are comprised. A good simple example in the STk
distribution is the labeled entry (Lentry.stklos). Eg:

(define-class <Labeled-entry> (<Tk-composite-widget> <Entry>)
  ((entry :accessor entry-of)
   (label :accessor label-of)
   ;; Fictive slots
   (title :accessor title
                 :init-keyword :title
                 :allocation :propagated
                 :propagate-to ((label text)))
 ...

in this case the class <Labeled-entry> has a slot 'title which it
inherits directly from the 'text slot of its label.

-- 
Mr Andrew Dorrell                                *
Faculty of Engineering             /---\  Whoo?      *
University of Technology, Sydney   (o o) /     *
AUSTRALIA                          ( : )            .
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                                                    *

Received on Thu Mar 26 1998 - 02:06:17 CET