db_connect: Could not connect to paper db at "wotug@dragon.kent.ac.uk"
db_connect: Could not connect to paper db at "wotug@dragon.kent.ac.uk"
%T Focussing on Traces to Link VCR and CSP
db_connect: Could not connect to paper db at "wotug@dragon.kent.ac.uk"
%A Marc L. Smith
db_connect: Could not connect to paper db at "wotug@dragon.kent.ac.uk"
%E Ian R. East, David Duce, Mark Green, Jeremy M. R. Martin, Peter H. Welch
%B Communicating Process Architectures 2004
%X View\-Centric Reasoning (VCR) replaces CSP\[rs]s perfect
observer with multiple, possibly imperfect observers. To
employ view\-centric reasoning within existing CSP models
requires a bookkeeping change. Specifically, VCR introduces
parallel events as a new primitive for constructing traces,
and distinguishes two types of event traces: histories and
views. Previously, we gave the operational semantics of VCR,
and demonstrated the utility of parallel event traces to
reason for the first time unambiguously about the meaning of
the Linda predicate operations rdp() and inp(). The choice
of using an operational semantics to describe VCR makes
direct comparison with CSP difficult; therefore, work is
ongoing to recast VCR denotationally, then link it with the
other CSP models within Hoare and He\[rs]s Unifying Theories
of Programming. Initial efforts in this direction led to a
comparison of VCR with Lawrence\[rs]s HCSP. In this paper,
we present some recent insights and abstractions \- inspired
by modern quantum physics \- that have emerged whilst
contemplating parallel event traces in light of the unifying
theories. These insights lead to a more natural expression
of VCR traces, in the sense that they more closely resemble
CSP traces, thus forming a basis for linking VCR and CSP.