RE: Re[2]: [cgmo-webcgm] Highlight test

[Lofton Henderson <lofton@rockynet.com>]

At 04:07 PM 6/14/2006 -0700, Galt, Stuart A wrote:
>Hello,
>
>My confusion may have started because in step 2 I remove the
>highlight on "C" but it still remains highlighted.  I assume that this
>is because of the nested structure in this CGM and the previous call to
>highlight "B" (that contains "C").

FWIW, I still would have expected that "C" (and all that it contains) 
should have gone "off".  The spec says:

=====
state of type boolean

     A true value will highlight the nodes, whereas false will remove the 
highlight.
=====

It doesn't say, "...; false will remove highlight, but ONLY IF it was 
previously set explicitly on that node by a call to highlight() with that 
node in the argument list."  (If that's what's meant, clarification of the 
wording might be in order.)

>[...]
>If highlighting is a state system and that when you turn on highlighting
>for circle B.  The entire contents of B (which includes "C" and "D") is
>highlighted.

If we intend that "C" -- whose contents were incidentally highlighted 
because they are also contents of "B", which received the call 
"highlight(B, true)" -- should stay highlighted when it the user tries to 
turn it off with "highlight(C, false) ... that seems a strange and 
surprising result to the unwary!  At the very least, some explanation in 
the text is in order, if that is the intention.  Some people would not 
guess this behavior without some better hints in the text.

Thoughts?

One small follow up on my earlier comment...

[...]
> > Maybe that would be a good clarification comment -- that
> > highlight(someObject) is identical to:  #id(someObject,
> > newHighlight) or #id(someObject, addHighlight).  Which one?
> > I'd say the 2nd, 'addHighlight'.  Thoughts?

Oops, about my statement "highlight(someObject, true) is identical to ..."

The problem with such an example is that there is no symmetrical "off" 
example.  I.e., there is no fragment "#id(someObject,...)" that is 
equivalent to "highlight(someObject, false)."  There is #id(*, 
clearHighlight), but only the wildcard "*" (all objects) is allowed -- you 
can't name a single object in place of "*".

-Lofton.