Students enrolled in this class are expected to check this web page regularly. Lecture notes and important other material will be posted here.
Course Description
CS522 is an advanced course on semantics of programming languages. Various semantic approaches and related aspects will be defined and investigated. Executable semantics of various programming languages and paradigms will be discussed, together with major theoretical models.
 Meetings: W/F 12:30  1:45, 1131 Siebel Center
 Professor: Grigore Rosu (Office: SC 2110, WWW: http://cs.illinois.edu/grosu, Email: grosu@illinois.edu)
 Office hours: Tu 13, but also by appointment, very flexible (held by Grigore Rosu in SC 2110)
Newsgroup and Piazza Page
Web Interface to CS522
CS522 Piazza Page
Lecture Notes, Useful Material
The links below provide you with useful material for this class, including complete lecture notes. These materials will be added by need.



HW1 (due Tuesday, February 5)

Do the following exercises, all from the book material above (pages 80/81): Exercise 30; Exercise 32; Exercise 33; Exercise 35 (do it only for the addition); Exercise 36.

 Conventional Semantic Approaches

HW2 (due Friday, February 15)

The following exercises are from the book material above. Do them only in Maude (that is, not on paper) by modifying the provided Maude code, with the exception of Exercise 81 which needs to be done only on paper (that is, not in Maude): Exercise 42 (page 92); Exercise 56 (page 137); Exercise 70 (page 155); Exercise 81 (page 168; write this up on paper, or put it into a PDF); Exercise 83 (page 169).


HW3 (due Wednesday, February 27)

Combine all the individual extensions of IMP provided in the zip archive into the IMP++ language. Read the book material above for all the technical details. You should create a subfolder of imp called 6imp++, and that should have four subfolders, one for each semantic style. Provide also three IMP++ programs.


HW4 (due Monday, March 11)

Same as HW3 but for the three additional semantic approaches discussed in the lecture notes above: MSOS, RSEC, and CHAM. Handle also a short essay discussing the advantages and limitations of each of the semantic approaches discussed so far in class, assigning a (justified) score between 1 and 10 to each of them. For the essay, please use an editor if your handwriting is as bad as mine or worse :)

 Lambda Calculus and Combinatory Logic

HW5 (due Wednesday, March 27)

Complete the code snipped above. That covers knowledge about untyped lambdacalculus, fixedpoints, combinatory logic, and de Bruijn nameless represenations.

 SimplyTyped Lambda Calculus
 Basic notions: type system, equational semantics, models, completeness. Slides
HW6 (due Friday, April 5)

Proposition 4, Exercise 6, Exercise 7, Exercise 9, and Proposition 8.

 Category theory: definition, diagrams, cones and limits, exponentials. Slides
 Cartesian Closed Categories as models for simplytyped lambdacalculus. Slides
HW7 (due Friday, April 19can also take the weekend if needed)

Exercises 5 and 6 from the slides on CCCs (nothing from the slides on category theory).

 Recursion, Types, Polymorphism

HW8 (due Tuesday, April 30)

Consider the PCF language with callbyvalue (note that the slides above define the callbyname variant, but we discussed the changes needed for callbyvalue in class). Give it a smallstep, a bigstep, and a denotational semantics in Maude, using the representations of these semantic approaches discussed in the first part of the class. Provide also 5 (five) PCF programs that can be used to test all three of your semantics. You can use the builtins provided as part of the previous HW (you should only need the generic substitution from there).


Extra credit (due Wednesday, May 8)

This extracredit HW has the same weight as the previous 8 HWs and is meant to help you increase your overall score, if you want to. It has two problems. The first is to define a type checker for the parametric polymorphic lambdacalculus (or System F). The second is to define a type checker for the subtype polymorphic lambdacalculus. In both cases, make sure that you also include the conditional and a few examples showing that your definition works. Feel free to pick whatever syntax you want for the various constructs (both for terms and for types).
