RE: Something is missing in Component Pascal

From: [at]} <support{>
Date: Thu, 3 Jul 2003 17:46:07 +0200

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Dear Wojtek,


Having read your recent contributions to the BlackBox mailinglist I would
like to emphasize some important points:

1) Turning stack-allocated record objects into pointers that can be stored
in heap objects is outright live-threatening. Next time the garbage
collector runs, BlackBox will most likely vanish from your screen, because
stack objects are collected upon return of the containing procedure. That's
why the language does not support this.

2) Your question indicates that you keep walking deeper and deeper into a
maze that has no exit and that you should not have entered in the first
place. To store the data you are displaying in your dialog the example
posted by Marc Matin is absolutely the right approach here, only in your
case not all record fields are simple types and you will have to write a few
lines of code to traverse the tree the tree control binds to.

3) To store data you can use Stores.Writer and Reader (i.e. the Rider
concept) without having to create a Stores.Store. Just process the record
field by field and call the appropriate rider methods. On a first glimpse,
this field-wise writing may seem inconvenient, but when using a Stores.Store
you'll have to do exactly the same thing just at a different place: in the
Externalize method.


Regards,

Wolfgang,
Oberon microsystems, Inc.

--------------------------------------------

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Received on Thu Jul 03 2003 - 17:46:07 UTC