Writing instrument interfaces with xf/tktcl

Tcl is an embedded control language written in C, running primarily under Unix and with an interpreted C look-and-feel. Tk is an X11 toolkit based on tcl. Xf is an application builder for tk. The entire package is public domain and available from sprite.berkeley.edu. This paper discusses the use of tk to develop a user interface for OSIRIS, an infrared camera/spectrograph now operational on the OSU Perkins 1.8m telescope. The good and bad features of the development process are described

Slisp: A Flexible Software Toolkit for Hybrid, Embedded and Distributed Applications

We describe Slisp (pronounced ‘Ess-Lisp’), a hybrid Lisp–C programming toolkit for the development of scriptable and distributed applications. Computationally expensive operations implemented as separate C-coded modules are selectively compiled into a small Xlisp interpreter, then called as Lisp functions in a Lisp-coded program. The resulting hybrid program may run in several modes: as a stand-alone executable, embedded in a different C program, as a networked server accessed from another Slisp client, or as a networked server accessed from a C-coded client. Five years of experience with Slisp, as well experience with other scripting languages such as Tcl and Perl, are summarized. These experiences suggest that Slisp will be most useful for mid-sized applications in which the kinds of scripting and embeddability features provided by Tcl and Perl can be extended in an efficient manner to larger applications, while maintaining a well-defined standard (Common Lisp) for these extensions. In addition, the generality of Lisp makes Lisp a good candidate for an application-level communication language in distributed environments

Portability of Prolog programs: theory and case-studies

(Non-)portability of Prolog programs is widely considered as an important factor in the lack of acceptance of the language. Since 1995, the core of the language is covered by the ISO standard 13211-1. Since 2007, YAP and SWI-Prolog have established a basic compatibility framework. This article describes and evaluates this framework. The aim of the framework is running the same code on both systems rather than migrating an application. We show that today, the portability within the family of Edinburgh/Quintus derived Prolog implementations is good enough to allow for maintaining portable real-world applications.Comment: Online proceedings of the Joint Workshop on Implementation of Constraint Logic Programming Systems and Logic-based Methods in Programming Environments (CICLOPS-WLPE 2010), Edinburgh, Scotland, U.K., July 15, 201

Context sensitive user interfaces

This paper presents a conceptual design model for user interfaces (MASS1) and a general formalism for dialogue specification (Interaction Scripts) which are the most important components of an approach to the methodological, iterative design of Interactive Systems from formal, model-based specification of both the application and the User Interface (UI). This approach allows the integration of both dialogue and application semantics from the beginning of the design process, by using prototypes derived from both specifications. Assuming that all the application semantics is available at early design stages, the MASS model defines a set of guidelines that will enforce the designer to create user interfaces that will present a prophylactic instead of the usual therapeutic behaviour. By a prophylactic behaviour it is meant, metaphorically, that the UI will exhibit a behaviour that prevents and avoids both syntactic and semantic user errors, in contrast with the most usual therapeutic, or error recovery, behaviour. The dialogue specification formalism(Interaction Scripts) despite being general, in the sense that it may be applied to the specification of any kind of dialogue, is specially suited to the specification of UIs with the behaviour prescribed by the MASS design model. In addition, it is independent from concrete environment details, therefore allowing for different implementations of the same specification, that is, different looks and feels. The operational semantics of the Interaction Script notation is also presented in terms of Petri-Nets that are automatically generated from the Interaction Script specification of the dialogue controller

rpanel: Simple Interactive Controls for R Functions Using the tcltk Package

In a variety of settings it is extremely helpful to be able to apply R functions through buttons, sliders and other types of graphical control. This is particularly true in plotting activities where immediate communication between such controls and a graphical display allows the user to interact with a plot in a very effective manner. The tcltk package provides extensive tools for this and the aim of the rpanel package is to provide simple and well documented functions which make these facilities as accessible as possible. In addition, the operations which form the basis of communication within tcltk are managed in a way which allows users to write functions with a more standard form of parameter passing. This paper describes the basic design of the software and illustrates it on a variety of examples of interactive control of graphics. The tkrplot system is used to allow plots to be integrated with controls into a single panel. An example of the use of a graphical image, and the ability to interact with this, is also discussed.