For the [Seaside] FAQ: Making the back button work

[Tom Phoenix]

On Dec 31, 2007 3:08 AM, Philippe Marschall
<philippe.marschall at gmail.com> wrote:

> states
>     ^Array with: self
>
> Because the contents of self (the content of the body instance
> variable) changes ower time and needs to be backtracked. Else you
> could use the back button to go to a state where a different body was
> displayed.

Thanks; this is very helpful.

Unless I'm missing something, there is nothing preventing a web user
from using a cached page to follow a link or (re)submit a form that is
no longer valid in the current context. When that happens, unless the
old links have expired from Seaside's cache, the callbacks fire. If I
want my application to recognize when the user has submitted something
that's no longer valid, I have to put a check into each callback. Is
that right?

For example, suppose my application implements a card game, and the
user chooses to draw a new card. If I want the application to prevent
them from going back and choosing a different game action, since
they've now seen the new card, I need to check at each link (i.e. game
action choice) that the game state hasn't changed to disallow that
choice.

WAComponent>>isolate: seems related, but I can't find documentation on
how to use it. Is that what I'm looking for?

Thanks!

--Tom Phoenix