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Channel and Gate

The following channel declaration defines a channel with name C:
\begin{smalltab} {\bf channel}($C$).\end{smalltab}

We use the term gate to denote a service access point to a communication channel. Gates use the same name as the corresponding channels.

Definition 1594

We define the following communication formulas as complementary to Definition 4.2, where operators ``!'' and ``?'' are called offer and accept respectively.
\begin{smallenum} \item G {\bf !} ($T_{1}, T_{2}, ..., T_{n}$) \item G {\bf ?} ($T_{1}, T_{2}, ..., T_{n}$)\end{smallenum}

(1) sends out a list of terms through gate G, (2) blocks until a list of terms arriving at gate G unify with T1, T2, ..., and Tn as a whole.

Definition 1600

We define active rules as having the following form:
\begin{smalltab} {\bf on-arrival}\=({\bf gate}(G), $T_{1}, T_{2}, ..., T_{n}$) :- \\ \\ gt$p_{1}, p_{2}, ..., p_{m}$.\end{smalltab}


Du Li
8/25/1999