Prism - Invariants, and pre/post conditions - update

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Just found out that I can do this too

public invariants
  Overdraft >= 0 : ’OverdraftGreaterThanOrEqualToZero’;
  Balance + Overdraft >= 0 : ’BalancePlusOverDraftGreaterThanOrEqualToZero’;
end;


Then in my handler routine I get that message!

if not IsValid then
  throw new Exception(ErrorMessage);


Excellent :-)

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