Authors
Margaret Burnett & Martin Erwig
Abstract
We have been working on a unit system for end-user spreadsheets that is based on the concrete notion of units instead of the abstract concept of types. In previous work, we defined such a system formally.
In this paper, we describe a visual system to support the formal reasoning in two ways. First, it supports communicating and explaining the unit inference process to users. Second and more important, our approach allows users to change the system's reasoning by adding and customizing the system's inference rules.
Sample
The reasoning system presented here specifically focuses on logical relationships, but on deriving them and using them to detect errors, not to determine cell values or to define a program per se. Hence, it produces a static analysis reasoning about a visual program (spreadsheet), not a program itself.
Publication
2002, Human Centric Computing Languages and Environments, September, pages 140-148
Full article
Visually customizing inference rules about apples and oranges
