Creating an Undo palette

Richard Gaskin ambassador at fourthworld.com
Thu Dec 8 14:46:20 EST 2011


Bernard Devlin wrote:
> I'm puzzled by Ken's remark about running out of IDs.  What is the upper
> limit to the number of IDs?

About 2 billion, which seems like a lot but think about:

Suppose you create and delete and recreate complex objects like a 
dataGrid, each of which contains hundreds of objects.  Do that several 
thousand times, and consider the life of the document.    If it's in use 
for a few years, the possibility of reaching the ID limit is no longer 
merely theoretical.

Once the max number of IDs has been used, a wide range of unpredictable 
behaviors start happening.   You can try this yourself by setting the ID 
of an object to the highest possible value, and then clone it.   The 
clone will be created, but it cannot be selected, and attempts to set 
its properties fail.  IIRC from the last time I tested this, nor error 
is thrown, it just stops working normally and enters into a netherland 
of oddities.

I would feel more comfortable about the dataGrid and other complex 
objects if I new there was a plan in place to raise the ID limit.....

--
  Richard Gaskin
  Fourth World
  LiveCode training and consulting: http://www.fourthworld.com
  Webzine for LiveCode developers: http://www.LiveCodeJournal.com
  LiveCode Journal blog: http://LiveCodejournal.com/blog.irv




More information about the Use-livecode mailing list