Hi John,
I think the other answers all very much sorted out your problem.
But i still want to insist that the *magic number* won't help you.
Try this:
open two workspaces.
tell both to create textual references on drop
drop any morph on one of them
inspect the textual reference in the _other_one_
I'm pretty sure your inspector will show you an undefined Object.

Why is this?
What you're looking for is the identity of the morph.
The workspace has a special feature called local bindings (or so).
By this you can refer to Objects textually, just like local or temporal
variables.
When a morhp is dropped the workspace gets to know the identity (by th
UI).
It then creates a new binding by 'thinking of' a name and binding it to
the Object.
There is no such thing as a global name for every Object. Allthough
there are global names for some Objects (Like World, ...). Any Object is
reachable in one way or the other >from one of these globally visible
Objects (otherwise it would get garbage collected). This is why you
nearly allways will find a way to wade all the Objects some of the
globals know and find your desired object. But this is almost never the
right way to go.

Regards,
Torge
John Hinsley wrote:
> 
> Torge Husfeldt wrote:
> >
> > Hear John,
> > You don't need that number!
> > The number is generated >from some internals of the morph when it is
> > dropped on the workspace. Then the new binding is created for _this_
> > workspace. I'm pretty sure that even if you guessed the right number you
> > wouldn't be able to kill the morph with WorldTimeMorph12345 delete.
> > Because there is no binding before. (This should be true for other
> > workspaces even after you generated the textual representation).
> >
> > On the other hand I'm pretty sure you do something like:
> > WorldTimeMorph new
> > somewhere in your code. Fine. Just make sure you change that to
> > <myInstanceVariable> := WorldTimeMorph new
> > and everything is fine.
> > Now you can do:
> > <myInstanceVariable> delete
> > anywhere you want (that is: the instance variable must be visible
> > there).
> > No magic numbers involved.
> 
> I think what I was missing was that WorldTimeMorph (at least, the
> initializeLocally part of it) is all class side and thus won't behave
> like "normal" morphs in this respect. Hence my messing about with magic
> numbers.
> 
> But, try it: if you do drop a WorldTimeMorph on a workspace you can then
> use the generated "textual reference" (worldtime + the magic number) and
> delete works fine on that. The problem then becomes one of obtaining
> that number reliably! -- some kind of way of getting that from a
> workspace might be useful, though.
> 
> Still, Ned's line
> 
> World allMorphsDo: [ :ea | (ea isKindOf: WorldTimeMorph) ifTrue: [ ea
> delete ]]
> 
> does the trick very nicely indeed.
> 
> Thanks
> 
> Cheers
> 
> John
> 
> --
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> destroy themselves and have money to burn on 3rd party tools to keep
> your
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