Order-sorted equational logic improves the expressivity of many-sorted equational logic by adding the notion of subsorts. In the standard approach, sorts are unrelated and can be thought of as denoting disjoint sets. Many-sorted equational logic is the basis for algebraic specifications, rewriting techniques, unification theory, and equational programming. This chapter discusses order-sorted equational computation. The type inference algorithm calculates the appropriate and principle types.We implement the algorithm in Java using the observer design pattern. This type inference system allows us, to declare method parameters and local variables without type annotations. This means that Java 5.0 methods often don't have the principle type which is contradictive to the OOP-Principle of writing re-usable code.This has caused us to develop a Java 5.0 type inference system which assists the programmer by calculating types automatically. But intersection types are not implemented in Java 5.0.

Furthermore there are methods whose principle types would be intersection types. The termVector>is for example a correct type in Java 5.0.Considering all that, it is often rather difficult for a programmer to recognize whether such a complex type is the correct one for a given method or not. As a result very complex types can arise. With the introduction of Java 5.0 the type system has been extended by parameterized types, type variables, type terms, and wildcards.

Tunify app subtitles