A survey of functional programming language principles

Research in the area of functional programming languages has intensified in the 8 years since John Backus' Turing Award Lecture on the topic was published. The purpose of this paper is to present a survey of the ideas of functional programming languages. The paper assumes the reader is comfortable with mathematics and has knowledge of the basic principles of traditional programming languages, but does not assume any prior knowledge of the ideas of functional languages. A simple functional language is defined and used to illustrate the basic ideas. Topics discussed include the reasons for developing functional languages, methods of expressing concurrency, the algebra of functional programming languages, program transformation techniques, and implementations of functional languages. Existing functional languages are also mentioned. The paper concludes with the author's opinions as to the future of functional languages. An annotated bibliography on the subject is also included

Formally-based tools and techniques for human-computer dialogues

With ever cheaper and more powerful technology. the proliferation of computer systems, and higher expectations of their users, the user interface is now seen as a crucial part of any interactive system. As the designers and users of interactive software have found, though, it can be both difficult and costly to create good interactive software. It is therefore appropriate to look at ways of "engineering" the interface as well as the application. which we choose to do by using the software engineering techniques of specification and prototyping. Formally specifying the user interface allows the designer to reason about its properties in the light of the many guidelines on the subject. Early availability of prototypes of the user interface allows the designer to experiment with alternative options and to elicit feedback from potential users. This thesis presents tools and techniques (collectively called SPI for specifying and prototyping the dialogues between an interactive system and its users. They are based on a formal specification and rapid prototyping method and notation called me too. and were originally designed as an extension to me too. They have also been implemented under UNIX*. thus enabling a transition from the formal specification to its implementation. *UNIX is a trademark of AT&T Bell Laboratorie