Sheet-Defined Functions: Implementation and Initial Evaluation

Spreadsheets are ubiquitous end-user programming tools, but lack even the simplest abstraction mechanism: The ability to encapsulate a computation as a function. This was observed by Peyton-Jones and others [14], who proposed a mechanism to define such functions using only standard spreadsheet cells, formulas and references.

This paper extends their work by increasing expressiveness and emphasizing execution speed of the functions thus defined. First, we support recursive and higher-order functions, while still using only standard spreadsheet notation. Secondly, we obtain fast execution by a careful choice of data representation and compiler technology.

The result is a concept of

sheet-defined functions

that should be understandable to most spreadsheet users, yet offer sufficient programming power and performance to make end-user development of function libraries practical and attractive.

We outline a prototype implementation Funcalc of sheet-defined functions, and provide a case study with some evidence that it can express many important functions while maintaining good performance.