Mike F. Cowlishaw

The design of the REXX language

One way of classifying computer languages is by two classes: languages needing skilled programmers, and personal languages used by an expanding population of general users. REstructured eXtended eXecutor (REXX) is a flexible personal language designed with particular attention to feedback from its users. It has proved to be effective and easy to use, yet it is sufficiently general and powerful to fulfil the needs of many demanding professional applications. REXX is system and hardware independent, so that it has been possible to integrate it experimentally into several operating systems. Here REXX is used for such purposes as command and macro programming, prototyping, education, and personal programming. This paper introduces REXX and describes the basic design principles that were followed in developinigt.

A large-scale computer conferencing system

This paper discusses the relationships between computer-mediated communications and other forms of communication and describes a particular computer conferencing system in use within IBM. The system described is quite large, with over three thousand contributors and over twenty thousand readers. We discuss the structure of the system, the actions that users can take, and the ways in which the system is being used. Neither the definitions presented nor the system described are intended to be the last, or only, word on the subject; as computer-mediated communications and distribution become more and more important in the business and professional communities, we will need more ways of thinking about communication systems and about information distribution in general.

LEXX—a programmable structured editor

Many sophisticated and specialized editing programs have been developed in recent years. These editors help people manipulate data, but the diversity complicates rather than simplifies computer use. LEXX is an editing program that can work with the syntax and structure of the data it is presenting, yet is not restricted to just one kind of data. It is used for editing programs, documents, and other material and hence provides a consistent environment for the user regardless of the editing task. The new live parsing technique used by LEXX means that it can be programmed to handle a very wide variety of structured data. The structure information is, in turn, used to improve the presentation of data (through color, fonts, and formatting), which makes it easier for people to deal with the text being edited.

The early history of REXX

REXX is a procedural language with many novel features. Its goal was to make programming easier in the belief that getting the design right for people to use is more important than providing for easy implementation. REXX development depended on the use of electronic mail. As a result, and perhaps uniquely for a programming language, there is an essentially complete historical record of the design process and discussions. This article describes the early history of REXX, illustrated by quotations from the electronic mail record and from other contemporary documents.<<ETX>>

NetRexx-an alternative for writing Java classes

This paper describes a new human-oriented programming language, called NetRexx, which has been designed as an alternative to the Java language. The reference implementation of NetRexx compiles to the Java Virtual Machine and allows programmers to create programs and applets for the Java environment faster and more easily than by programming in Java. NetRexx classes and Java classes are entirely equivalent-NetRexx can use any Java class (and vice versa). Using existing Java classes is especially easy in NetRexx, as the different types of numbers and strings that Java expects are handled automatically by the language. NetRexx combines the strengths of two very different programming languages, Rexx and Java. The result is a language which is tuned for both scripting and application development, and is therefore genuinely general-purpose.