Program Fragments, Linking, and Modularization

Abstract

Module mechanisms have received considerable theoretical attention, but the associated concepts of separate compilation and linking have not been emphasized. Anomalous module systems have emerged in functional and object-oriented programming where software components are not separately typecheckable and compilable. In this paper we provide a context where linking can be studied, and separate compilability can be formally stated and checked. We propose a framework where each module is separately compiled to a self-contained entity called a linkset; we show that separately compiled, compatible modules can be safely linked together. 1 Introduction Program modularization arose from the necessity of splitting large programs into fragments in order to compile them. As system libraries grew in size, it became essential to compile the libraries separately from the user programs; libraries acquired interfaces that minimized compilation dependencies. A linker was used to patch compiled fragmen...