Bootstrapping the Object Oriented Operating System Merlin: Just Add Reflection

Pure object oriented programming languages (like Self) present a very abstract view of the hardware to the programmer, and so are unlikely candidates for system software development. The Merlin operating system adds a reflective structure to Self that allows the programmer to move cleanly between different abstraction levels to get around this problem, but this introduces other difficulties in the form of circular definitions. This paper shows how a step by step introduction of reflection into the system can handle this apparently impossible situation. 1 The Problem The Merlin Project[AJ93] was created to make computer systems simple enough to be used by novices, yet powerful enough not to be quickly outgrown by them. So it was natural to choose a simple and powerful language like Self[US87] to implement this object-oriented operating system. Most systems offer different tools, languages and even ideas to such groups as novices, power users, application programmers, system programmers..