Question about when is xforms-value-changed dispatched

Dear Working Group,

I have a question about whether xforms-value-changed must be (not be) 
dispatch from a calculate when it does not change its value. The 
attached testcase illustrates that a change to a dummy variable will 
mark the calculate for recalculation but the value will not change 
(unless dummy=''). Is implementations required to check if the 
calculated value is identical with the existing one?

Best regards,
David

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David Landwehr (david.landwehr@solidapp.com)
Chief Executive Officer, SolidApp
Web: http://www.solidapp.com
Office: +45 48268212
Mobile: +45 24275518
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