Notes on timed concurrent constraint programming

A constraint is a piece of (partial) information on the values of the variables of a system. Concurrent constraint programming (ccp) is a model of concurrency in which agents (also called processes) interact by telling and asking information (constraints) to and from a shared store (a constraint). Timed (or temporal) ccp (tccp) extends ccp by agents evolving over time. A distinguishing feature of tccp, is that it combines in one framework an operational and algebraic view from process algebra with a declarative view based upon temporal logic. Tccp has been widely used to specify, analyze and program reactive systems. This note provides a comprehensive introduction to the background for and central notions from the theory of tccp. Furthermore, it surveys recent results on a particular tccp calculus, ntcc , and it provides a classification of the expressive power of various tccp languages.