Using Automatic Memoization as a Software Engineering Tool in Real-World AI Systems

Memo functions and memoization are well-known concepts in A I programming. They have been discussed since the Sixties and are ofien used as ezamples in introductory programming texts. However, the automation of memoization as a practical sofiware engineering tool f o r A I systems has not received a detailed treatment. This paper describes how automatic memoization can be made viable on a large scale. It points out advantages and uses of automatic memoization not previously described, identifies the components of an automatic memoization facility, enumerates potential memoization failures, and presents a publicly available memoization package (CLAMP) f o r the Lisp programming language. Experience in applying these techniques in the development of a large planning system is briefly discussed.