Abstract A New Look at Pattern Matching in Abstract Data Types

In this paper we present a construction smoothly integrating pattern matching with abstract data types. We review some previous proposals [19, 23, 20, 6, 1] and their drawbacks, and show how our proposal can solve them. In particular we pay attention to equational reasoning about programs containing this new facility. We also give its formal syntax and semantics, as well as some guidelines in order to compile the construction efficiently.