Reflections on a systems programming language

A particular systems implementation language, Bliss, has been in active use at Carnegie-Mellon for over two years. At this point the language has been used for several compilers, a conversational programming system, an i/o support system, a discrete event simulation system, and other diverse applications. The authors, together with others, have been responsible for the design, implementation, evolution, and evaluation of the language. Drawing on the past two years' experience this paper attempts a critical evaluation of the language - its failures as well as its successes - with an eye toward the development of future systems implementation languages.