Patent ID: 7500226

Claim:
A computerized method of state dependent constraint checking, the method comprising: receiving a program listing and a representation of a constraint; creating control logic comprising: determining when updates are proposed for an updated variable in the program listing upon which a constraint expression for the constraint depends; determining whether the constraint would be violated if the updated variable is updated with a proposed value; removing data indicating a relationship between the constraint and a set of variables upon which the constraint depends before the constraint is modified by updating the updated variable; determining one or more accessed variables which are accessed during evaluation of the constraint expression, wherein the evaluation is performed on the constraint expression as modified by the updated variable being updated to the proposed value; and creating data indicating relationships between the constraint and the one or more accessed variables, wherein the set of variables upon which the constraint depends changes through re-establishing the constraint such that the set of variables includes the one or more accessed variables; and verifying the constraint by executing a translated version of the program listing which comprises at least in part the control logic.