The Design of
		      Object-Oriented Meta-Architectures
			  For Programming Languages


				      by
		     Guruduth Banavar and Gary Lindstrom

			       Technical Report
				 UUCS-94-033

		       Department of Computer Science
			     University of Utah
			 Salt Lake City, UT 84112 USA


				  June 1994

				   Abstract

This paper is a survey of the design of four object-oriented
meta-level architectures for programming languages.  We present
overviews and compare the salient features of the meta-architectures
of Smalltalk, Common Lisp Object System (CLOS), a Scheme Compiler, and
Etyma, our framework for modular systems.  This comparison clarifies
important architectural aspects of the surveyed systems, such as the
space of concepts captured by the architectures, and the abstractions
that embody similar language concepts across the architectures.  We
find that there are considerable differences in the goals and
conceptions of these architectures, yet they can all be used for
similar applications.  Finally, we point out some strengths and
weaknesses of the architectures surveyed.