## Why Undergraduates Should Learn the Principles of Programming Languages

Programming languages are the medium through which we describe computations. More specifically, we use the model provided by a programming language to discuss concepts, formulate algorithms, and reason about problem solutions. Programming languages define models tailored to thinking about and solving problems in intended application areas. For example, the C language provides a model close to a computer’s underlying hardware […]. The languages used in practice change continuously as advances in our field and the broadening uses of technology change how we model and express computation. At its core, the study of programming languages examines the principles and limitations of computing (or programming) models, the effective design and use of systems or languages based on these models, and methods to compare their relative strengths and weaknesses in particular contexts.”

Why Undergraduates Should Learn the Principles of Programming Languages, ACM SIGPLAN Education Board, February 6, 2011, Page 1]

## Objectives of the Course

This course is an introduction to the theory and design of programming languages. To develop high-assurance software - software for which we can give strong evidence that the software will do what it is supposed to do and nothing more - a formal description of the ‘meaning’ and behaviour of programs is required. Hence two fundamental aspects of the study of programming languages are their syntax, and their formal semantics. High-assurance software is not only needed for safety-critical software, but also for program transformations, such as carried out by optimising compilers.

Topics covered in this course include formal semantics of programming languages (such as operational, denotational and axiomatic), type systems, higher-order functions and lambda calculus, concurrency, and communication.

## Learning Outcomes

Upon successful completion, students will have the knowledge and skills to:

- Understand the role of theoretical formalisms, such as operational and denotational semantics
- Apply these semantics in the context of programming languages
- Evaluate differences (advantages/disadvantages) of these theoretical formalisms
- Create operational or denotational semantics of simple imperative programs
- Analyse the role of types in programming languages
- Formalise properties and reason about programs
- Apply basic principles for formalising concurrent programming languages

## Assumed Knowledge

Students need to have understanding of discrete mathematics, and basic knowledge in a programming language such as C.

The course makes use of a number of discrete mathematics concepts. Students may find the course very difficult without MATH1005/MATH6005 or equivalent discrete mathematics background.

Completion, or undertaking of automata and/or logic courses such as COMP1600 or COMP2620 are desirable for getting the most out of the course, but not essential.

## Course philosophy and teaching strategies

The learning focus in this course is primarily on lectures and assignments, plus a mid term project which you can use to demonstrate your skills acquired until then. While marks are assigned to the assignments, their primary purpose is to give you concrete tasks with deadlines to help you structure your learning.

## Lecturers and Tutors

**Peter Höfner**(Convenor and Lecturer) mail

cecs.anu.edu.au/people/peter-hoefner**Fabian Muehlboeck**(Co-Lecturer)**Abhaas Gohal**(Tutor)**Weiyou Wang**(Tutor)

If you’re stuck, then you can reach out for help anytime—the course help page or course forum is a good place to start.