LILK — Static analysis of REDUCE code

Abstract

One of the advantages of fancy compile time type checking systems besides avoiding runtime checking overhead is the early detection of program bugs and conceptual problems. Unfortunately, large bodies of old code exist which were written for untyped or dynamically typed systems, which leave such problems to be detected during execution, often much later and only in response to peculiar or unusual input. A typical example of this syndrome is the computer algebra system REDUCE. The experience of fighting valiantly with this in the past, has led now to an attempt to improve on the situation by applying inferencing techniques to add type information to the current source code in a relatively painless way. I present here a preliminary report on this work, showing that the complexly related type scheme of an algebra system is particularly suitable for this.