Streams and managers

Abstract

The sole effect of expression evaluation in a functional programming language is the production of a resultant value. This absence of side-effects greatly facilitates both the formal characterization and the concurrent execution of functional programs. Unfortunately, the absence of side-effects also conflicts with conventional means of achieving input/output, inter-process communication, and resource allocation. By incorporating the history of communication into a stream, functional programs can be written for I/O and communication. Using the stream concept, managers may be written to control access to resources shared by several processes.