An object-oriented, concurrent, reflective language based on Hybrid Group Architecture. ABCL/R2 was produced by <[email protected]>, <[email protected]>, <[email protected]>, <[email protected]>, at the Tokyo Institute of Technology in 1992.

As a reflective language, an ABCL/R2 program can dynamically control its own behaviour, such as scheduling policy, from within a user-program. This system has almost all functions of ABCL/1 and is written in Common Lisp.