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.

The ease of understanding, maintaining, and developing a large program depends crucially on how it is divided up into modules. The possible ways a program can be divided are constrained by the available modular programming facilities ("module system") of the programming language being used. Experience with the Standard-ML module system has shown the usefulness of functions mapping modules to modules and modules with module subcomponents. For example, functions over modules permit abstract data types (ADTs) to be parameterized by other ADTs, and submodules permit modules to be organized hierarchically. Module systems with such facilities are called higher-order, by analogy with higher-order functions. Previous higher-order module systems can be classified as either opaque or transparent. Opaque systems totally obscure information about the identity of type components of modules, often resulting in overly abstract types. This loss of type identities precludes most interesting uses of hi...

Objective ML is a small practical extension to ML with objects and top level classes. It is fully compatible with ML; its type system is based on ML polymorphism, record types with polymorphic access, and a better treatment of type abbreviations. Objective ML allows for most features of object-oriented languages including multiple inheritance, methods returning self and binary methods as well as parametric classes. This demonstrates that objects can be added to strongly typed languages based on ML polymorphism.

... This paper introduces Smart Packets and describes the Smart Packets architecture, the packet formats, the language and its design goals, and security considerations.

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Mixin modules, modules and extended value binding