1. More on Type Checking

2. Conversion and Coercion Int C; A = 1.5 + C;

3. Overloading An id binds to >1 semantic entity in same scope Pascal: f = f + 1 Fortran/PL1: + int or real addition Ada: A(i) Many languages: function decls with different parameter numbers/types Why? What are the challenges in implementing overloaded id’s?

4. Resolving overloaded symbols Determine unique meaning – use context Operators (non-ids) Ids

5. Another example

6. Overriding in Java

7. Polymorphic Call Sites

8. Polymorphic Functions: one function decl, multiple type args

9. Polymorphism, Overloading, Overriding

10. Type Checking Summary Exercise: With a partner, Outline the main issues you need to know to implement a type checker.