The programming walkthrough is a method for assessing how easy or hard...

. We present a visual language that serves as a novel form of feedback in a Programming by Demonstration (PBD) interface. The language explicitly represents data, such as files, with unique icons and implicitly represents operations by changes to data icons, so that operations reflect the changes seen in the interface when executed. In addition, the language is used to provide feedback to the user by indicating loops and inferred sets, specifying parameters, etc., and is integrated into other parts of the PBD system, such as the editor. This forms a close union between the interface, the PBD system and the program representation and helps bridge the gap between the user's mental model of the programming process and the actual programming task. 1 Introduction In his classic 1983 article, Ben Shneiderman introduced the concept of a "direct manipulation" interface, in which objects on the screen can be pointed to and manipulated using the mouse and keyboard[25]. The Apple Macintosh, intr...

We present a new visual programming language and environment that serves as a form of feedback and representation in a Programming by Demonstration system. The language differs from existing visual languages because it explicitly represents data objects and implicitly represents operations by changes in data objects. The system was designed to provide non-programmers with programming support for common, repetitive tasks and incorporates some principles of cognition to assist these users in learning to use it. With this in mind, we analyze the language and its editor along cognitive dimensions. The assessment provides insight into both strengths and weaknesses of the system, suggesting a number of design changes. This work supported by the National Science Foundation under grant number IRI-9020089. Additional support provided by the Hertz Foundation and the AAUW. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing t...