CS 457 Functional Languages

Course Description

Prerequisites: CS 202, 311.

Upon the successful completion of this course students will be able to:

1. Describe the key characteristics of the functional paradigm.
2. Use a functional language to write simple programs manipulating lists and trees.
3. Use higher order functions, including maps, folds, and composition, to perform tasks on lists.
4. Define algebraic datatypes to model useful domains.
5. Define and use appropriate higher order functions on arbitrary algebraic data types.
6. Illustrate how higher-order function values can be used to store data.
7. Convert functional abstract data type specifications into implementations.
8. Prove properties of simple functional programs using equational reasoning and induction.
9. Explain and use polymorphic functions and data types, and interpret type error messages.
10. Write functional programs that perform I/O, using either monadic or direct methods.
11. Explain the differences between eager and lazy evaluation, and their significance.
12. Write programs using simple infinite data structures.
13. Explain the basic implementation considerations for a functional language.
14. Design and implement a non-trivial application program in a functional language.

Major Topics:

Topics that we expect to cover include:

• Introduction, basic concepts, expressions, comprehensions, the standard prelude
  • Examples: fractals; Excell Tables

• More about lists -- Library
  • Defining functions
  • Pattern matching
  • Recursive definintions

• Algebraic Datatypes
  • More on pattertn matching
  • Trees and graph visualization via Graph Viz

• Music (as an example of a combinator library)
  • Haskore
  • Possibly some interaction with music TeX or similar

• Testing and reasoning
  • Quick check
  • Equational Reasoning

• Higher order functions
  • Folds
  • Church numerals (lambda calculator)

• Laziness, with possible examples including:
  • memoization
  • arrays and finite functions
  • prime sieve
  • DFS
  • A rush hour puzzle solver

• Overloading and classes
  • including a second look at the Excell and Quickcheck libraries

• Monads
  • Basic concepts
  • I/O

• Practical Applications, possibly including some of the following:
  • Database and Internet applications (more combinators?)
  • HTML combinators
  • Graphics via OpenGL

Texts for the Class

• Lecture notes and other supplementary material will be posted on-line via the daily record.
• Many documents will be formatted as Microsoft Word (*.doc) or in Adobe Portable Document Format (*.pdf). Be sure you can access and print these kinds of documents. Free resources for these kinds of documents include Open Office, and Adobe Reader.

Course Website

The class webpage maintains a "Daily Record" which catalogs every class activity. Activities include lectures, reading assigments, writing assignments, projects, etc. These are catalogued by day, both when they are assigned and when they are due. You should check the daily record before every class.

Assignment submission procedure.

We will use the D2L system to electronically submit homework.

Things needed

• PSU Odin account and registration in the course. These will give you D2L access, which is required for homework submission. If you don't have an account you must get one immediately. You can do so online at: https://www.account.pdx.edu/ After following those three steps you will need to verify your identity at the help desk in the basement of Smith.
• Access to a computer with internet capability.
• Haskell Implmentation. A running implementation of Haskell. I recommend the Glasgow Haskell Compiler, version 7.6.3 (or higher) and use of the GHCI interface. You should get and install the Haskell Platform. It might be possible to use Hugs interpreter for the early assignments, but later assignments will require the use of libraries, and it is necessary that all students to use the same libraries not all of which are available under Hugs. I also think the GHCI error messages are better.
• Text. There is no required text for this class, but we have provided pointers to useful books and other reading material on the resources page.

Grading and Assignments

• 10% Class participation, including
  1. Attendance
  2. Class Participation and Discussion (blackboard work, code reviews, team activitites)
• 40% Weekly programming assignments
• 30% Midterm
• 20% Project (be done as small teams of 2-3 persons)

Work not turned in, unacceptable work or an unexcused absence from class when the work was done receives no credit. Excused absences requires that students make arrangements with the instructor to turn in missed work be turned in as soon as possible. It is your job to make arrangements with me.

Readiness to learn means that you will come to class with questions and insights to offer to others and be prepared to discuss the assigned reading. We will be learning from each other and your voice is important. Your participation grade will include attendance, participation in class discussions, participation in online discussions, and group work in class on smaller design problems and case studies.

Student Conduct/Plagiarism:

The following constitutes conduct proscribed by Portland State University for which a student or Recognized Student Organization or group is subject to disciplinary action:

Academic dishonesty. Academic dishonesty is the act of knowingly or intentionally seeking to claim credit for the work or effort of another person or participation in such acts. This includes, but is not limited to: (a) cheating, (b) fraud, (c) plagiarism, such as word for word copying, using borrowed words or phrases from original text into new patterns without attribution, or paraphrasing another writer's ideas; (d) The buying or selling of all or any portion of course assignments and research papers; (e) Performing academic assignments (including tests and examinations) for other persons; (f) Unauthorized disclosure or receipt of academic information; (g) Falsification of research data; and (h) Unauthorized collaboration.

Source: Office of Student Affairs at Portland State University, Code of Student Conduct and Responsibility. A copy of the full code can be found at http://www.pdx.edu/dos/codeofconduct. A copy can be obtained from The Office of Student Affairs at Smith Memorial Center Room 433.

Disability Resources

If you are a student with a document disability, who is registered with the Disability Resource Center, please contact the instructor to arrange any needed academic accomodations. For more information about the Disability Resource Center, see http://www.drc.pdx.edu/.