I have released a new version of the LaTeX ucs package yesterday, which is version 2.2. It fixes the bug that is described in the TeX StackExchange question Conflict between ifxetex and ucs under pdflatex/xelatex – why?.
In the Theory Lunch of the last week, James Chapman talked about the MU puzzle from Douglas Hofstadter’s book Gödel, Escher, Bach. This puzzle is about a string rewriting system. James presented a Haskell program that computes derivations of strings. Inspired by this, I wrote my own implementation, with the goal of improving efficiency. This blog post presents this implementation. As usual, it is available as a literate Haskell file, which you can load into GHCi. Continue reading
A recent language extension of the Glasgow Haskell Compiler (GHC) is the
Constraint kind. In this blog post, I will show some examples of how this new feature can be used. This is a write-up of my Theory Lunch talk from 7 February 2013. The source of this article is a literate Haskell file, which you can download and load into GHCi. Continue reading
One of the most important ingredients of Haskell is its type system. Standard Haskell already provides a lot of useful mechanisms for having things checked at compile time, and the language extensions provided by the Glasgow Haskell Compiler (GHC) improve heavily on this.
In this article, I will present several of Haskell’s type system features. Some of them belong to the standard, others are only available as extensions. This is a write-up of a talk I gave on 31 January 2013 during the Theory Lunch of the Institute of Cybernetics. This talk provided the basics for another Theory Lunch talk, which was about the
Constraint kind. Continue reading
Two months ago, we started the theory lunch meetings at the Institute of Cybernetics. In these meetings, we have lunch together and discuss all kinds of interesting things related to theoretical computer science. We also started the Theory Lunch blog, where an article is posted for every lunch session. I used three of the lunch meetings to talk about ideal monads, and published summaries of my talks in the following articles: Continue reading
Yesterday I finished my new paper Temporal Logic with “Until”, Functional Reactive Programming with Processes, and Concrete Process Categories, which will appear in the proceedings of PLPV ’13 and is also available online. I have already given two talks on topics of this paper, one at the Joint Estonian–Latvian Theory Days at Medzābaki and another one at the Theory Seminar of the Institute of Cybernetics. Continue reading