Type Checking in an Imperfect World

Abstract

We present an algorithn for the determination of run-time types which functions in the presence of errors, and show that it provides more information than that obtained using a previously published algorithm.In Section 1 we define the problem and state the requirements for a practically useful type prediction algorithm. In Section 2 we introduce a model programing language and in Section 3 define type inference rules for that language. Section 4 presents a type prediction algorithm and Section 5 describes how to apply the results to solve the problems stated in Section 1. Section 6 presents an example of our procedure and demonstrates how previous work does not satisfy all requirements.