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<DIV><SPAN class=689171917-02032006><FONT face=Arial color=#0000ff size=2>Thanks
Jeff, this helps clarify my proposal.</FONT></SPAN></DIV>
<DIV><SPAN class=689171917-02032006><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=689171917-02032006><FONT face=Arial color=#0000ff size=2>I
propose instead the ability to </FONT></SPAN><SPAN
class=689171917-02032006><FONT face=Arial color=#0000ff size=2>say that a
constraint should be checked exclusively
on the associated events. </FONT></SPAN></DIV>
<DIV><SPAN class=689171917-02032006><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=689171917-02032006><FONT face=Arial color=#0000ff size=2>I
think that this would put things nicely into the hands of the
meta-modeler.</FONT></SPAN></DIV>
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<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left><FONT
face=Tahoma size=2>-----Original Message-----<BR><B>From:</B>
gme-users-bounces@list.isis.vanderbilt.edu
[mailto:gme-users-bounces@list.isis.vanderbilt.edu] <B>On Behalf Of </B>Jeff
Parsons<BR><B>Sent:</B> Thursday, March 02, 2006 10:56 AM<BR><B>To:</B>
gme-users<BR><B>Subject:</B> RE: [gme-users] Constraint
problem<BR><BR></FONT></DIV>
<DIV dir=ltr align=left><SPAN class=999095316-02032006><FONT face=Arial
color=#0000ff size=2>What about the case where GME is used with other tools,
for example one that generates</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=999095316-02032006><FONT face=Arial
color=#0000ff size=2>XML for GME to import. If this tool had a bug and
generated something that violated the</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=999095316-02032006><FONT face=Arial
color=#0000ff size=2>constraint in question, wouldn't "Check All" be the only
way to catch it?</FONT></SPAN></DIV><BR>
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style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px solid; MARGIN-RIGHT: 0px">
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<HR tabIndex=-1>
<FONT face=Tahoma size=2><B>From:</B>
gme-users-bounces@list.isis.vanderbilt.edu
[mailto:gme-users-bounces@list.isis.vanderbilt.edu] <B>On Behalf Of
</B>Larry H.<BR><B>Sent:</B> Thursday, March 02, 2006 10:32 AM<BR><B>To:</B>
gme-users<BR><B>Subject:</B> [gme-users] Constraint
problem<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV><FONT face=Arial size=2><SPAN class=168504815-02032006>I'm having a
problem defining a constraint that concerns a change in number of
children in a container. My intention is to check
this constraint on an event, like "onlostchild", and to prevent the
action by setting the constraint's Priority=1. My problem is to find
an approach that does not subsequently trigger a violation when the user
chooses the 'Check All' action of the Constraint
Manager.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=168504815-02032006></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=168504815-02032006>It is my current
belief that there is no way to define such a constraint. The reason is
that the focus of this constraint is "change", whereas the focus of the
Constraint Manager, in general, is "current
state". Constraints concerning "change" typically
involve knowing "state before" and "state after". Have I failed
to consider something?</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=168504815-02032006></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=168504815-02032006>One thing that
occurs to me is that the Constraint Manager might consider not checking
constraints on "Check All" that are checked on events with Priority=1.
The intuition is that, since such event-based constraints can only result in
aborting the action, there is simply no reason to check them again on "Check
All". </SPAN></FONT><FONT face=Arial size=2><SPAN
class=168504815-02032006>Such a feature would allow the desired constraint
to be defined quite simply with a "false" predicate.</SPAN></FONT></DIV>
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