Homework # 9
due November 4

Reading

Please read Chapter 15 in your textbook.

Problems

Please do the following problems

Check your answers against the solutions in the book, but do not turn in anything unless you have questions.

Please do the following problems:

Turn in your answers to these problems.

Proofs

Adding T-SUB drastically changes a type system, especially the canonical forms lemmas. You are provided with proof of type soundness for the simply-typed lambda calculus with records. You need to change the proofs to add subtyping.

The skeleton file for this homework, not only includes records and the proof of soundness but also the subtyping relation. You need to do several things:

About this document



John Tang Boyland 2008-10-28