The authors of this book cast the problem as solving abstract equations
over language and study the most general (largest) solutions under the
synchronous and parallel composition operators. They also apply such
equations to languages associated with important classes of automata
used for modeling systems, e.g., regular languages as counterparts of
finite automata, FSM languages as counterparts of FSMs. The authors
investigate the largest subsets of solutions closed with respect to
various language properties; in particular, classes of the largest
compositional solutions (defined by properties exhibited by the
composition of the solution and of the context). The first algorithm to
compute the largest compositionally progressive solution of synchronous
equations is provided. This approach unifies in a seamless frame
previously reported techniques.