Earlier this week I got a Lego Mindstorms EV3 robotics kit. I was aware there is a Haskell binding, but I didn’t know it is compatible only with the earlier NXT generation of the Mindstorms line, at least according to the Wikipedia page on EV3. I’m hoping to find out today if the NXT Haskell library can nevertheless be used with the EV3. If not, I’m likely to start writing a Haskell library for EV3.

# Category Archives: functional programming

# Gave a Talk on Function Totality

As announced last week, yesterday I gave a talk on function totality at the Institute of Electrical and Electronics Engineers, Croatian Section. The talk was located at the University of Zagreb at the Faculty of Electrical Engineering and Computing. Slides used during the talk are freely available. The talk was in Croatian.

## Giving a Talk at IEEE on Function Totality

### Status

The upcoming Tuesday I will be giving a talk at the IEEE Croatian Section on function totality. The talk will take place at the University of Zagreb, the Faculty of Electrical Engineering and Computing.

# Function Totality: Abstraction Tool in Programming

Edsger Dijkstra said the following of abstraction:

“The purpose of abstraction is not to be vague, but to create a new semantic level in which one can be absolutely precise.”

Abstraction is a cornerstone of programming a complex software system. Without it, a complex software system is a complicated software system. In this article I will explore an important tool in achieving abstraction in programming: function totality.

## Proof Assistant in Teaching

### Status

Benjamin C. Pierce writes what it is like to use a proof assistant to teach programming language foundations.

# Hooked on Dependent Types

Just this morning these two books landed my mailbox:

The Little Typer is a new book on dependent type theory, written by Daniel P. Friedman, an author of The Little Schemer, and David Thrane Christiansen, an Idris contributor. Verified Functional Programming in Agda is a book by Aaron Stump, on using dependent types in Agda to prove various properties of programs. After having read the Type-driven Development with Idris book by Edwin Brady, I am hoping these two books will significantly expand my knowledge of and improve my skills in type theory, theorem proving and typed functional programming. Looking forward to reading the books! If you haven’t noticed by now, I got hooked on dependent types!

# Typed Functional Programming and Software Correctness

Software testing has been an important, if not prevalent way of checking software correctness. In this article I will tell how have my doctoral dissertation on testing and verification of imperative software as well as my work experience after the studies led me to typed functional programming, which consequently gave me a different perspective on automatic software testing. Furthermore, I’ll explain why functional programming and static type systems are important for software correctness.

## Wadler on Invented Programming Languages

### Status

Philip Wadler makes a fun note about today’s programming languages: “Most of you use programming languages that are invented, and you can tell, can’t you?” I recommend watching his whole talk Propositions as Types!

# Less bad MTL

I stumbled upon a recording of a talk by George Wilson on the monad transformer library (MTL) in Haskell. He goes on to demonstrate how monad transformers can be made more composable by using constraints instead of directly putting a monad transformer in the return type of a function. What is presented there is definitely an improvement, however it is still unsatisfactory. In particular, in his examples there is no separation of describing and running a program, which means everything happens in the IO monad (the MonadIO constraint in function signatures in the examples). In other words, anything goes and such functions are again too powerful.

## Idris for Haskellers

### Status

In case you are a Haskeller interested in learning Idris, check out a short list of things to look out for.