Actor-Based Concurrent Language

Actor-Based Concurrent Language is a family of programming languages, developed in Japan in the 1980s and 1990s.

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ABCL/1

ABCL/1 is a prototype-based concurrent programming language for the ABCL MIMD system, created in 1986 by Akinori Yonezawa, of the Department of Information Science at the University of Tokyo.
ABCL/1 uses asynchronous message passing among objects to achieve concurrency. It requires Common Lisp. Implementations in Kyoto Common Lisp and Symbolics Lisp are available from the author.

ABCL/c+

An implementation of ABCL/c+ is available from the ACM.

ABCL/R

ABCL/R is an object-oriented reflective subset of ABCL/1, written by Professor Akinori Yonezawa of Tokyo [Institute of Technology] in 1988.

ABCL/R2

ABCL/R2 is a second generation version of ABCL/R, designed for the Hybrid Group Architecture. It was produced at the Tokyo Institute of Technology in 1992, and has almost all the functionality of ABCL/1. It is written in Common Lisp. As a reflective language, its programs can dynamically control their behavior, including scheduling policy, from within a user-process context.