CS 430: Lecture 9 – Abstraction and Object-oriented Programming

Dear students, Computer scientists spend considerable time tinkering under the hood of their systems. Their clients, however, are happy to only have a few buttons to push to make those systems work. A simpler view of a complex system is called an abstraction. When a humane abstraction is available, clients can ignore irrelevant and low-level […]

CS 430: Lecture 8 – Activation

Dear students, Today we take a foray into a technical topic: the mechanics of calling functions. We might think this is information that is pretty well hidden from us when we’re writing in a high-level language. But abstractions leak. The way that functions are called bubbles up into the design of our languages. Having some […]

CS 430: Lecture 7 – Subprograms and Parameters

Dear students, Programs are recursive. They are built out of smaller chunks of code that are themselves programs. We call these smaller chunks of code subprograms. These subprograms organize our code into coherent pieces, with each piece solving a small computational task and deferring to other pieces as needed. We expect that we’ll write better […]

CS 430: Lecture 6 – Expressions and Control Structures

Dear students, The programs we write do many things: they facilitate communication, they walk a user through an interaction, they automate drudgery, they control physical artifacts, they store and retrieve data, and so on. Whatever a program’s final goal, many of its intermediate steps are concerned with producing and consuming information. This information is combined […]

CS 430: Lecture 5 – Haskell

Dear students, This class has hit upon several themes so far this semester. In week 1, we discussed the spectrum programming language features. In week 2, we discussed the ideas behind a language’s syntax and how source code is lexed and parsed. In week 3, we talked of how we name data with variables. In […]

CS 430: Lecture 4 – Types

Dear students, You know how in English nouns and verbs are independent? You can pick any noun and mix it with any nearly any verb to for a grammatical sentence. Butter dances. Fish sneeze. We have a similar situation in programming languages. The grammars of our languages allow us to mix data and operations in […]

CS 430: Lecture 3 – Variables

Dear students, Computer science has its roots in mathematics. It was the mathematicians who first had problems they wanted to mechanize. Computer science soon grew into a discipline of its own that appeals to people who don’t like mathematics. My hot take is that there’s one big reason for its success: computer science has more […]

CS 430: Lecture 2 – Syntax

Dear students, Today we look at the first steps of how a program becomes an executable. The source code that we write is a foreign language to the computer. It must be translated into a language that the machine does know. That’s the job of the compiler or interpreter. Translation is a process with multiple […]

CS 430 – Programming Languages


CS 430: Lecture 1 – Programming Languages

Dear students, Welcome to CS 430: Programming Languages! What’s this class about? Well, imagine you are a biology student taking a course on mammals and every lecture, lab, and homework is on cows. You wouldn’t really be a biologist at the end of the course. You’d be a cowist. A cow gives you one picture […]