From @IRAUN1.IRA.UKA.DE:kumar@ira.uka.de  Wed May 23 09:08:12 1990
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From: Ramayya Kumar <kumar%ira.uka.de@RELAY.CS.NET>
To: info-hol@CLOVER.UCDAVIS.EDU
Subject:  Temporal Operators


Dear HOL Users,
We are trying to implement "First-Order Predicate Logic with Temporal
Operators" in HOL and are having some problems with definitions.
All the material related to temporal logic and HOL, that we have seen so
far, deal with temporal abstraction between different levels of description.
We would like to describe circuits without time explicitly appearing
as a parameter. For example,

        "P means that P is true at the present time instant"
i.e. although t appears implicitly as the present time instant, it does
show up in the definition.

        NEXT (P) should be defined as P is true at the next time instant.

We would eventually like to describe sequential components using the temporal
operators in this fashion - e.g.

        ALWAYS((NEXT out) = in) defines a delay component.

Has anyone had any experience with such definitions. Any pointers would
be appreciated.

Thanks in advance,
Kumar

