Fundamentals of Programming Languages

Class meetings are Tuesdays and Thursdays 2:00pm-3:15pm in ECCR 1B51.

Please check the following calendar for the latest information about office hours and other class events.

All students should have received a welcome e-mail from me on how to get set up with the course tools. If you did not receive such a message, please send me an e-mail. All further correspondence will be via Piazza.

Instructor


Prof. Bor-Yuh Evan Chang
Regular Office Hours: Tue 3:15pm-4:00pm and Thu 1:00pm-1:45pm in ECCS 121C (inside ECCS 121)

Course Assistant


Nicholas V. Lewchenko
Regular Office Hours: Wed 2:30pm-3:30pm and Fri 10:30am-11:30am in ECCS 114G

Course Overview

This course introduces the fundamental principles behind modern programming language design, semantics, and implementation. Ultimately, you should come away with the ability to apply foundational programming language ideas and techniques to your own projects.

The course has two broad topics:

  • Introduction to Semantics and Type Systems: How do we describe programming languages? And which programs “make sense”?
  • Research Applications: Students will have the opportunity to consider other related topics of interest in the form of a course project, most often in the form of a survey of recent research on a topic of interest.

The first part of this graduate-level course focuses on the dynamic and static semantics of a variety of programming language features (e.g., “what does a function really mean?”). We will study structural operational semantics as a way to formalize the intended execution and implementation of languages. Operational semantics concepts and notation are widely used in modern programming language research. We will survey axiomatic semantics, which provides a basis for verifying programs. Axiomatic semantics underlie research efforts in formal verification and bug finding (e.g., SLAM, which led to Microsoft’s Static Driver Verifier). We will briefly look at denotational semantics as a prelude to abstract interpretation. Abstract interpretation also underlie research efforts in program analysis and bug finding (e.g., Astrée, which has been used by Airbus to analyze their flight control software).

The last part of the course covers special topics drawn from research in areas such as applications of program semantics to program analysis and verification.

Prerequisites

The prerequisites for this course are programming and mathematical experience with several different programming languages (e.g., C, ML, Java) with diverse computational models (i.e., imperative and functional), which may be satisfied by taking CSCI 3155 or equivalent. The ideal programming experience is experience implementing language tools, which may be satisfied by taking an undergraduate compilers course (e.g., CSCI 4555). The ideal mathematical experience is familiarity with mathematical logic and the ability to construct rigorous proofs (in particular by structural induction). Your desire to be exposed to this material is very important.

Advanced undergraduates may consider taking this course after talking with the instructor.

If you have not already taken these courses or if you have any concerns, please talk with the instructor. Proficiency in programming and mathematical logic is absolutely expected. This means that you should be able to pick up a new programming language with relative ease and are reasonably comfortable with inductive thinking.

Requirements

You will be responsible for the following:

  • Class Participation (5%). Participation includes both in-class and online discussion.
  • Homework Assignments (35%). There will be homework assignments for the first part of course. This is a project-based course, so assignments will be the main learning vehicle.
  • A Final Exam (30%).
  • A Final Project (30%). In the second part of the course, your time will be spent on a final project. You will create a final project that explores, extends, or experiments with the ideas in the course.
  • Reading. There will be required papers or book chapters to read.

Grading

Your overall grade will be determined using the ratio for the deliverables shown above. There is no predetermined curve (i.e., I hope everyone gets an A based on the level of mastery demonstrated).

Regrades

Any concern about an error in grading must be submitted within one week of when it is returned. Any coursework submitted for reconsideration may be regraded in its entirety, which could result in a lower score if warranted. To request a regrade, please go to the instructor’s office hours with your coursework and an explanation of what you believe the grading error to be.

Make-Up Exam Policy

There will be no special or make-up examinations for any student (except in the case of emergency or the stated special accommodations).

Redo Policy

This course is project-based, which means the learning is driven primarily by the homework assignments. To encourage iteration until mastery, you may “redo” any assignment via an oral interview with the instructor for a maximum of 90%. A “redo” must be completed within one week of when the assignment is returned. You may request one interview per assignment. However, you may discuss your solutions with the instructors in office hours as much as you like before requesting your regrade. You must submit your assignment on time to participate in a “redo”.

Extra Credit and Participation

Extra credit opportunities may be offered during the course semester. Extra credit is recorded separately from normal grades and are only considered after final grades have been calculated. If your final grade is just below a grade cutoff, extra credit may bump you up to the next grade. Finding a bug in the course materials that is then adopted is a standing offer for extra credit.

Pair Programming

You may sometimes be asked to work on homework assignments in pairs, enabling pair programming. Homework assignments are the main opportunity to learn material in this course and thus they count for a relatively small portion of your final grade. It is strongly advised that you work on all the problems in an assignment together so that you understand all of the material and are prepared for the exam. Everyone will submit assignments, and you must cite your partner explicitly. If necessary, you may switch partners between assignments, and you are responsible for all assignments individually (e.g., if your partner drops the course midway though an assignment, you still need to submit on time).

Workload

This is a graduate-level, active learning-based course. A high level of independent learning is expected.

Evaluation

Both your ideas and also the clarity with which they are expressed matter—both in your English prose, your mathematical writing, and your code!

We will consider the following criteria in our grading:

  • How well does your submission answer the questions? For example, a common mistake is to give an example when a question asks for an explanation. An example may be useful in your explanation, but it should not take the place of the explanation.
  • How clear is your submission? If we cannot understand what you are trying to say, then we cannot give you points for it. Try reading your answer aloud to yourself or a friend; this technique is often a great way to identify holes in your reasoning. For code, not every program that “works” deserves full credit. We must be able to read and understand your intent. Make sure you state any preconditions or invariants for your functions (either in comments or as assertions)

Integrity of the Course Materials

The development effort in the course materials, including the lab assignments, the exercises, and the exams, is significant. You agree that you will not share any course materials publicly or privately outside of your teams. The course materials, include your or anyone else’s solutions to the lab assignments, exercises, and exams. In particular, you agree not to post your solutions to the lab assignments in a public source code repository, such as public Github repositories. Please use private source code repositories for your work.

Note that there is no conflict with the Collaboration Policy described below. You are welcome and encouraged to support each other in the learning of the material.

Collaboration Policy

You are welcome and encouraged to work together in learning the material. If you worked with someone on an assignment, or if your submission includes quotes from a book, a paper, or a web site, you should thank the source. Bottom line, feel free to use resources that are available to you as long as the use is reasonable and you cite them in your submission. However, copying answers directly or indirectly from solution manuals, web pages, or your peers is certainly unreasonable. If you have any doubts in this regard, please ask the course staff.

You are allowed to discuss homework assignments with other students. However, in order to ensure that the work you submit is still your own, we insist that you adhere to a whiteboard policy regarding these discussions: you are not allowed to take any notes, files, or other records away from the discussion. For example, you may work on the homework at the whiteboard with another student, but then you must erase the whiteboard, go home, and write up your solution individually. We take your ability to recreate the solution independently as proof that you understand the work that you submit.

This policy is our attempt to balance the tension between the benefits of group work and the benefits of individual work. We ask that you obey the spirit of the policy, as well as the letter: ensure that all work you submit is your own and that you fully understand the solution. This is in your best interest: the exam constitutes a significant part of your final grade and it will draw heavily on the terminology, concepts, and techniques that are exercised in the homework. It is unlikely that you will be able to do well on the exam if you do not take full advantage of the learning opportunity afforded by the homework assignments.

Academic Dishonesty Policy. We will go by the Honor Code set forth by the University:

All students enrolled in a University of Colorado Boulder course are responsible for knowing and adhering to the academic integrity policy of the institution. Violations of the policy may include: plagiarism, cheating, fabrication, lying, bribery, threat, unauthorized access, clicker fraud, resubmission, and aiding academic dishonesty. All incidents of academic misconduct will be reported to the Honor Code Council (honor@colorado.edu; 303-735-2273). Students who are found responsible for violating the academic integrity policy will be subject to nonacademic sanctions from the Honor Code Council as well as academic sanctions from the faculty member. Additional information regarding the academic integrity policy can be found at honorcode.colorado.edu.

Academic sanctions may include, but is not limited to, a zero for the assignment or a failing grade for the course.

Course Communication

There are two main websites for this course. - Public. This public course website contains the course syllabus (this page) and publicly-available learning materials. - Private. The course Canvas contains any links that are limited to enrolled students. From Canvas, you will find resources like the Piazza discussion forum, private project repositories, submission links, grades, feedback, and sign-ups.

Texts

Supplemental Readings

The following are some other recommended resources:

Course Tools

Canvas

We will use Canvas for grades and protected resources.

Piazza

We will be using Piazza for online, outside-of-class discussion, which is accessed via the course moodle. Rather than emailing questions to the teaching staff, questions should be posted on the course piazza. I encourage you to make class-wide posts whenever possible, but there is an option to send an instructor-private message. You also have the option of posting anonymously.

Off-Campus Access

The CU library has instructions for off-campus access to certain online resources (e.g., ACM Digital Library).

Computing

For a Linux environment, check out the CSEL resources. CSEL maintains cloud coding environments, virtual machine environments, and remote access servers with SSH (elra-01 through elra-04.cs.colorado.edu).

Additional Policies

Classroom Behavior

We trust and expect everyone to behave in a civil and courteous manner.

In class, the course staff promises their undivided attention and reciprocally expects the same from you. In today’s world, this promise requires turning off transmitting devices, such as cell phones and wi-fi on notebook computers. The use of notebook computers should be discussed with the instructor and they should be used only for purposes directly relevant to the class discussion. Please notify the course staff if you encounter behavior that distracts from your learning.

We will also go by the policies set forth by the University:

Students and faculty each have responsibility for maintaining an appropriate learning environment. Those who fail to adhere to such behavioral standards may be subject to discipline. Professional courtesy and sensitivity are especially important with respect to individuals and topics dealing with differences of race, color, culture, religion, creed, politics, veteran’s status, sexual orientation, gender, gender identity and gender expression, age, disability, and nationalities. Class rosters are provided to the instructor with the student’s legal name. I will gladly honor your request to address you by an alternate name or gender pronoun. Please advise me of this preference early in the semester so that I may make appropriate changes to my records. For more information, see the policies on classroom behavior and the student code.

Disability Accommodations

We will go by the disability guidelines set forth by the University:

If you qualify for accommodations because of a disability, please submit to your professor a letter from Disability Services in a timely manner (for exam accommodations provide your letter at least one week prior to the exam) so that your needs can be addressed. Disability Services determines accommodations based on documented disabilities. Contact Disability Services at 303-492-8671 or by e-mail at dsinfo@colorado.edu. If you have a temporary medical condition or injury, see the Temporary Injuries guidelines under the Quick Links at the Disability Services website and discuss your needs with your professor.

Religious Observances

We will go by the policy for religious observances set forth by the University:

Campus policy regarding religious observances requires that faculty make every effort to deal reasonably and fairly with all students who, because of religious obligations, have conflicts with scheduled exams, assignments, or required attendance. we will try to accommodate religious conflicts in a reasonable manner. Please check the exam dates and submit all requests for adjustments within the first four weeks of class. See the campus policy regarding religious observances for full details.

Acknowledgments

This course is based on materials Prof. George Necula at the University of California, Berkeley, Prof. Westley Weimer at the University of Michigan, Prof. Robert Harper at Carnegie Mellon University, and Dr. Matthew A. Hammer.