[etoys-dev] Reverting a book page breaks project

[Bert Freudenberg]

On 11.08.2010, at 16:49, Bert Freudenberg wrote:

> On 11.08.2010, at 16:10, <kharness at illinois.edu> wrote:
> 
>> NB I get a bug report on page 7 and unless one already knows how to open the extra page controls the book ends there, too soon and too baffling for beginners. 
>> Page 10 of the book says " to be continued" but there is no book two for a successful beginner to find.
> 
> That project is already updated (though I have no idea what you mean with "bug report on page 7"):
> 
> 	http://tracker.squeakland.org/browse/SQ-668

I tracked down the problem - the "HaloCastle" project is indeed broken.

But this can be reproduced even in Etoys 4's Demon Castle: Run Etoys, click "Tutorials", "demon castle", navigate to page 8 using the book controls, click the left door to go back to pg. 7 - works fine. Now revert pg. 7, go to pg. 8, and click the back door again - boom.

The culprit seems to be #revertPageInner: which sends #deletePageAlongWithPlayers: which removes all player uni classes. Is this right? When I comment it out it works, but there certainly was a reason ... When copying the book page for later revert, are players copied, too? But it still breaks ...

- Bert -