Formal Software Verification


Bring your computer

Lecturer

Bas Spitters

Contact

We will be using the discussion board on brightspace for general discussions about the exercises, projects, and Coq.

Links

Course material

Coq During this course we will be using the Coq proof assistant. Coq is both a functional programming language, as well as a system that allows one to reason using formal proofs about one's programs. Information on installing Coq is available here. I recommend a recent version of Coq (8.13) and Coq Platform, especially on windows. Choose an IDE. I recommend either vscode or emacs.
One can read logical foundations in the browser and use jscoq for collaborative editing. This is still experimental though.

We will be using part of the online textbook Software Foundations by Benjamin C. Pierce et al.

Homework

The course includes a track of weekly exercises. Submission and approval of 10 mandatory assignments is required. Five assignments from the first seven weeks and five from the second.
Work in groups of two (maximally three) is encouraged. The exercises should be handed in each Friday following the TA session before 10:00.

Coq should accept the homework handed in as a .v file in its entirety. The exercise will not be graded if Coq does not accept the file. Use Admitted to make Coq accept incomplete proofs.

You are not allowed to use Coq tactics in the homework that we have not yet discussed (for example tauto, eauto and omega are forbidden).

Preliminary schedule

Monday 9:00-11:00 5427-140: Feedback and Lecture
Thursday 9:00-10:00 5427-140: Questions about homework

DateTopics Course material
week 35 Installing Coq
Basic inductive types
Proving using computation
Rewriting
Preface and Basics and Induction
week 36 Lists and Polymorphic functions
Lists and Polymorphic functions
week 37 Tactics and Logic
Tactics and Logic
Week 38 Inductively defined propositions
IndProp
Week 39 ProofObjects, IndPrinciples
Maps, ProofObjects, Rel, IndPrinciples
Week 40 Imp
Imp
Week 41 Auto
Auto, AltAuto
Week 43 SmallStep
SmallStep, Types
Week 44 Simple Type Theory
Stlc, StlcProp
Week 45 Type Checking
More Stlc, TypeChecking
Week 46 Programming with Dependent types
Lecture, Equations manual, Equations introduction, Slides
Week 47 Type Classes

Week 48 Monads
v-file, Exercises
Week 49 QuickChick

Coq project

The course finishes with a Coq project, a list of suggestions can be found here and here. You may also invent a Coq project yourself or do a variation or extension of one of our suggested projects. If you invent a project yourself or use a variation of the suggestions, you have to discuss it with the lecturer.

You are allowed to work in groups. You may also write the report together. However, you are fully responsible for the code and the report. The oral exam will test your understanding.

In order to complete the Coq project, you have to make the following deliverables:

The written report has to be 5 to 10 pages, should be in academic style, and should include:

  1. Name and student number.
  2. A small introduction with at least a description of the project you have chosen. You should not just copy the description from the projects file.
  3. A description of the problems you have encountered during the project and how you have solved these. If you had multiple solutions in mind, describe these, and explain why you have picked the one you have used.
  4. A conclusion with at least your experience using Coq: what did you like and what you did not like.

You should not include unnecessarily long excerpts of Coq code, just use small fragments to illustrate a point. Informal proofs should be formulated in the way taught during the course. Do not paraphrase Coq proofs in natural language by writing: and now we apply tactic X so our goals becomes Y.

Grading

Grade reflects an overall assessment of:

Only students with approved exercises can attend the oral exam and thus pass the course.

The grade of the Coq project is based on the following items:

  1. Correctness: whether the Coq definitions and lemmas correctly model the problem.
  2. Completeness: whether all lemmas are proven (e.g. no lemmas omitted and proofs finished with admit or Admitted).
  3. Style: whether the Coq code follows the style guidelines (e.g. use of Case tactic, sensible variable names and use of implicit arguments).
  4. Effectiveness: whether the definitions and proofs are given in an effective way (e.g. no useless proof steps and the induction tactic not used blindly).
  5. Report: style, presentation, language and correctness of the report.

During the oral exam we will test your understanding of the project. E.g. by asking you to create a small extension of the project, to explain proofs of the project in an informal way, to query you about the contents of your report, or ask general questions about the contents of the course.
Bring your laptop!