From Procedures, Objects, Actors, Components, Services, to Agents -- A Comparative Analysis of the History and Evolution of Programming Abstractions

The objective of this chapter is to propose some retrospective analysis of the evolution of programming abstractions, from em procedures, em objects, em actors, em components, em services, up to em agents, %have some compare concepts of software component and of agent (and multi-agent system), %The method chosen is to by replacing them within a general historical perspective. Some common referential with three axes/dimensions is chosen: em action selection at the level of one entity, em coupling flexibility between entities, and em abstraction level. We indeed may observe some continuous quest for higher flexibility (through notions such as em late binding, or em reification of em connections) and higher level of em abstraction. Concepts of components, services and agents have some common objectives (notably, em software modularity and reconfigurability), with multi-agent systems raising further concepts of em autonomy and em coordination. notably through the notion of em auto-organization and the use of em knowledge. We hope that this analysis helps at highlighting some of the basic forces motivating the progress of programming abstractions and therefore that it may provide some seeds for the reflection about future programming abstractions.