Com S 641 Lecture -*- Outline -*-

* first-order typing for imperative languages (chapter 11)

** typing (11.1)
   Q: what is different between this type system and the one in chapters 7-8?
   Q: can you explain the rules for clone and let?

** examples of typings (11.2)
   Q: is there any type that can be used like "void" in C?
      look at the move methods on page 143
   Q: is the subtyping more flexible for movable points in an
      imperative language?
   Q: why is it useful for typing that clone is built-in?

** classes and global behavior change (11.3)
   Q: what happens to instances when methods of a class are modified?
   Q: when methods of a superclass are modified?

** subject reduction (11.4)
   Q: what's the basic problem in determining types for values ("results")?
   Q: what invariant is being maintained by the type system?
   Q: why do result typing need a store type?
   Q: how are stores and store types connected to stacks and their types?
   Q: can you give a simple example of a store type and a store that has it?
   Q: of a stack type and a stack that has it?
   Q: can you explain Lemma 11.4-1?

   They will need to read through the proof on their own, but ask for
   questions.