Most discussions about monads, even in F#, start by looking at the well-known standard monads for handling state from Haskell. The reader monad gives us a way to propagate some read-only state, the writer monad makes it possible to (imperatively) produce values such as logs and the state monad encapsulates state that can be read and changed. These are no doubt useful in Haskell, but I never found them as important for F#. The first reason is that F# supports state and mutation and often it is just ea[...]

As someone doing programming language research, I find it really interesting to think about how programming language research is done, how it has been done in the past and how it should be done. This kind of questions are usually asked by philosophy of science, but only a few people have discussed this in the context of computing (or even programming languages). So, my starting point was to look at the classic works in the general philosophy of science and see which of these could tell us something about[...]

At last, the long wait is fianlly over! After 4 years of waiting, the fully managed implementation of the C# compiler [codenamed "Roslyn"][roslyn] has been finally released. In the recent months, "Roslyn" has been slowly turning into [vaporware][vaporware], but thanks to the recent breakthrough, the team made an enormous progress over the last two months and even implemented a number of new C# 6.0 features. The C# 6.0 compiler, together with the full source code has been released today! UPDATE: In [...]

Do you need to convince your friends & family that programming can be fun? For the last Christmas, I got a puzzle as a gift. It is a number of small cubes, joined together, that can be rotated and folded to form a bigger (4x4x4) cube. We spent the last few days of the year with family and a couple of friends and I left the puzzle on the table. Every time I walked around, someone was playing with it without much success. In the end, I said that if noone solves it until 31 December, I'll write a program to[...]

× Click here to see the result live! For the last few years, the Japanese F# community has been running the F# Advent Calendar (2010, 2011, 2012). Each advent day, one person writes an article about something interesting in F#. I have been following the advent calendar last year on Twitter and when the planning started for this year, I offered to write an article too. You might have noticed that I posted a Japanse version of the article in December as part of the advent calendar 2013. A[...]