In an orthogonally persistent programming system, data is treated in a manner independent of its persistence. This gives simpler semantics, allows the programmer to ignore details of long-term data storage and enables type checking protection mechanisms to operate over the entire lifetime of the data. The ultimate goal of persistent programming language research is to reduce the costs of producing software. The work presented in this thesis seeks to improve programmer productivity in the following ways: • by reducing the amount of code that has to be written to construct an application; • by increasing the reliability of the code written; and • by improving the programmer’s understanding of the persistent environment in which applications are constructed. Two programming techniques that may be used to pursue these goals in a persistent environment are type-safe linguistic reflection and hyper-programming. The first provides a mechanism by which the programmer can write generators that, when executed, produce new program representations. This allows the specification of programs that are highly generic yet depend in non-trivial ways on the types of the data on which they operate. Genericity promotes software reuse which in turn reduces the amount of new code that has to be written. Hyper-programming allows a source program to contain links to data items in the persistent store. This improves program reliability by allowing certain program checking to be performed earlier than is otherwise possible. It also reduces the amount of code written by permitting direct links to data in the place of textual descriptions. Both techniques contribute to the understanding of the persistent environment through supporting the implementation of store browsing tools and allowing source representations to be associated with all executable programs in the persistent store. This thesis describes in detail the structure of type-safe linguistic reflection and hyper-programming, their benefits in the persistent context, and a suite of programming tools that support reflective programming and hyper-programming. These tools may be used in conjunction to allow reflection over hyper-program representations. The implementation of the tools is described.

Parallel processing can provide the huge computational resources that are required to solve todays grand challenges, at a fraction of the cost of developing sequential machines of equal power. However, even with such attractive benefits the parallel software industry is still very small compared to its sequential counterpart. This has been attributed to the lack of an accepted parallel model of computation, therefore leading to software which is architecture dependent with unpredictable performance. The Bulk Synchronous Parallel (BSP) model provides a solution to these problems and can be compared to the Von Neumann model of sequential computation. In this thesis we investigate the issues involved in providing a modular programming environment based on the BSP model. Using our results we present Opal, a BSP programming language that has been designed for parallel programming-in-the-large. While other BSP languages and libraries have been developed, none of them provide support for libraries of parallel algorithms. A library mechanism must be introduced into BSP without destroying the existing cost model. We examine such issues and show that the active library mechanism of Opal leads to algorithms which still have predictable performance. If algorithms are to retain acceptable levels of performance across a range of machines then they must be able to adapt to the architecture that they are executing on. Such adaptive algorithms require support from the programming language, an issue that has been addressed in Opal. To demonstrate the Opal language and its modular features we present a number of example algorithms. Using an Opal compiler that has been developed we show that we can accurately predict the performance of these algorithms. The thesis concludes that by using Opal it is possible to program the BSP model in a modular fashion that follows good software engineering principles. This enables large scale parallel software to be developed that is architecture independent, has predictable performance and is adaptive to the target architecture.

The problems of semantics and translation for concurrent programming languages are studied in this thesis. A structural operational approach is introduced to specify the semantics of parallelism and communication. Using this approach, semantics for the concurrent programming languages CSP (Hoare's Communicating Sequential Processes), multitasking and exception handling in Ada, Brinch-Hansen's Edison and CCS (Milner's Calculus of Communicating Systems) are defined and some of their properties are studied. An operational translation theory for concurrent programming languages is given. The concept of the correctness of a translation is formalised, the problem of composing transitions is studied and a composition theorem is proved. A set of sufficient conditions for proving the correctness of a translation is given. A syntax-directed translation from CSP to CCS is given and proved correct. Through this example the proof techniques of this approach is demonstrated. Finally, as an application of operational semantics and translation, a proposal for implementing multitasking in Ada is given via a two-step syntax-directed translation.

We introduce a class of program editors that present a program using a rich set of transformations; we call these kinds of editors composable presentation editors. Proper use of these kinds of editors appears to lead to more expressive programs-programs whose structure are aligned with the problem they are trying to solve. By default, the composable presentation editor presents program elements textually as concrete syntax and enables typical editor commands on the program. Metadata on program elements control how the transformations are applied. Customized metadata can re-order, pictorialize, collapse, duplicate, or expand the displayed form of program elements and can additionally alter the available editor commands. We have developed a set of presentation techniques to be used by presentation designers (i.e., the programmers who design how a program is presented in the editor. These techniques relate to well-understood programming language design, editor design, and programming best-practices techniques including scoping, higher order functions, refactoring, prettyprinting, naming conventions, syntax highlighting, and text hovers. We introduce two implementations of composable presentation editors and a number of examples showing how programs can be made more expressive when presentation techniques are properly used. The first implementation is the ETMOP, an open editor, where a metaobject protocol is provided that allows language and editor designers to customize the way program elements are displayed. These customizations are called presenta- tion extensions and the corresponding presentation extension protocol acts in a way similar to the way that syntax macros extend the syntax of a language. The second implementation is Embedded CAL, a closed editor that uses these presentation techniques to embed one language (CAL) inside a host language (Java) through the use of presentation techniques, without changing the syntax or compiler of either language.

The object-oriented community is paying increasing attention to techniques for object instance encapsulation and alias protection. Formal techniques for modular verification of programs at the level of objects are being developed hand in hand with type systems and static analysis techniques for restricting the structure of runtime object graphs. Ownership type systems have provided a sound basis for such structural restrictions by being able to statically represent an extensible object ownership hierarchy. However, such structural restrictions may potentially have limitations on cases when more flexible reference structures are desired. In this thesis, we present a different encapsulation technique, called Effect Encapsulation, which confines side effects rather than object references. With relaxed restriction on reference structure, it is able to express certain common object-oriented patterns which cannot be expressed in Ownership Types. From this basis, we also describe a model of Object Validity --- a framework for reasoning about object invariants. Such a framework can track the effect and dependency of method calls on object invariants within an ownership-based type system, even in the presence of re-entrant calls. Moreover, we present an access control technique for protecting object instances. Combined with context variance, the resulting type system allows for a more flexible and useful access control policy, hence is capable of expressing more object-oriented patterns.

Bibliography: leaves 215-229. / viii, 229 leaves ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis presents a new method for performing incremental code generation in a distributed integrated programming environment. A prototype implementation of such an incremental code generator is also described. The study derives a new retargetable incremental instruction algorithm from a non-incremental instruction selection technique in the framework of a precise model of the underlying program representation. The resulting algorithm incrementally regenerates locally optimal object code after the replacement of a subtree in an abstract syntax tree program representation. / Thesis (Ph.D.)--University of Adelaide, Dept. of Computer Science, 1996

Thesis (M.S.)--Rochester Institute of Technology, 1989. / Includes bibliographical references.

Thesis (Ph. D.)--University of Adelaide, 1985. / Includes bibliographical references (leaves [238]-244).

Thesis (M.S.)--Ohio University, March, 2000. / Title from PDF t.p.

Thesis (Ph.D.) in Spatial Information Science and Engineering--University of Maine, 2007. / Includes vita. Includes bibliographical references (leaves 145-153).