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24hrs in F#

The easiest place to see what’s going on in the F# community is to follow the #fsharp hash tag on Twitter. The last 24hrs have been as busy as ever, to the point where it can be hard to keep up these days.

Here’s some of the highlights


Build Stuff conference to feature 8 F# speakers:

and workshops including:

FP Days programme is now live, and features key notes from Don Syme & Christophe Grand, and presentations from:

New Madrid F# meetup group announced:

F# MVP Rodrigo Vidal announces DNA Rio de Janeiro:

Try out the new features in FunScript at MF#K Copenhagen:

Mathias Brandewinder will be presenting some of his work on F# & Azure in the Bay Area

Let’s get hands on session in Portland announced:

Riccardo Terrell will be presenting Why FP? in Washington DC

Sessions featuring FsCheck, Paket & SpecFlow scheduled in Vinnitsa (Ukraine)


Get Doctor Who stats with F# Data HTML Type Provider:

Major update to FSharp.Data.SqlClient:

ProjectScaffold now uses Paket:

Microsoft Research presentation on new DBpedia Type Provider:


More F#, Xamarin.Forms and MVVM by Brad Pillow

Cross-platform MSBuild API by Robin Neatherway

Hacking the Dream Cheeky Thunder Missle Launcher by Jamie Dixon:

Want more?

Check out Sergey Tihon’s F# Weekly!

The Last Assignment

Back in November last year, my eldest son and I popped over to the Insomnia Gaming Festival in Telford to take part in a game jam organised by Global GameCraft. (Today I  bumped into the source again on a USB stick).

The theme for the day was “The Last Assignment”. We decided to go with a text based adventure game loosely based on the Dirty Harry movie.

With just 7 hours on the clock we managed to put together quite a fun adventure game with ambient sound and graphics:

The Last Assignment - Start Screen

and picked up the prize for best storyline!

The Last Assignment - Insomnia Telford

Given the time constraints I decided to build the dialogue as a simple state machine using coroutines. In this scenario C# was my go to language as it provides basic iterator block support and a first class goto statement.

By building the game dialogue as a simple state machine I was able test it from the start as a console app and later easily integrate it into a graphical environment.

Here’s the state machine for the rookie scene:

public static IEnumerable<State> Rookie()
   yield return new State(
         "One way or another this will be your last assignment.\r\n" +
         "Just 2 weeks left on the force before you retire.\r\n" +
         "Back at the police station",
         "You get a black coffee and a donut",
         "A chai latte and a cup cake") { Theme="70s reflective;bullpen"};
   if (Choice.Taken == 2) goto imposter;
   yield return new State(
         "Your new partner introduces himself.",
         "You give him a stern look",
         "Ignore him") { Theme = "70s reflective;bullpen" };
   yield return new State(
         "\"Why do they call ya 'Dirty Harry'?\"",
         "Make up your own mind kid",
         "Turn up your eye brow"
         ) { Theme = "70s reflective;bullpen" };
   yield break;
   Game.Ended = true;
   yield return new State(
         "You have been exposed as an imposter.\r\n" +
         "Cops don't chai latte, keep it real!")
         { Theme = "end game mp3;bullpen" };


which looked like this:

Rookie Scene

If you fancy having a play, the source for the game as a console app is available here:

Have fun!

Unboxing FP

How hard is it to get started in functional programming?

Let’s have a look at how quickly you can get started on a selection of simple expression-oriented programming languages.

Today let’s try Clojure, Elm, F#, Haskell and OCaml.

Online REPL

No install required just point your browser at a URL and you’re off:

Language Online REPL


Each language has an easy to use online REPL with simple lessons to get you through the basics. Elm’s online offering lets you edit multi-line programs, as does Try F#, which also includes intellisense in the online editor.

Development environment

Now you’ve covered the basics you probably want to install a lightweight development environment and start building larger programs:


I found LightTable very quick to install and setup. The editor comes with psychedelic colours to help you track opening and closing parenthesis:

FizzBuzz Clojure

I’ve been using Stuart Holloway’s Programming Clojure book as a guide.


Elm has a very usable online editor, a simple installable REPL, and a wonderful playground feature with Elm Reactor:


If you’re on Windows and have Visual Studio installed then you’ve already got F#. From the file menu click New and select a new F# project or script file.

No Visual Studio, no problem, for Windows the Tsunami IDE is a fast 25MB download, which gives you the latest compiler and an editor with intellisense:

Tsunami IDE

On Mac I’d recommend Xamarin Studio and for Linux MonoDevelop or Emacs.

Functional Programming using F# and Dave Fancher’s recent Book of F# are both great introductory texts.


The Haskell platform gives you a compiler and REPL from a simple 100MB install. A combination of a text editor along with the REPL gets you going in no time:

Haskell FizzBuzz

As a guide I’ve been using the Real World Haskell book. Learn you an Erlang some Haskell for great good! looks like a fun read too.


Like Haskell, OCaml is bundled in a simple installer and includes the compiler and REPL. Choose your own editor and use the REPL to explore your programs.

I recently picked up OCaml from the Very Beginning and More OCaml, which are both nice concise introductions.

OCaml From The Very BeginningMore OCaml


Using an online REPL you can get started with any of these languages in seconds, and there are plenty of lightweight install options too. Combine that with a good selection of learning resources from books to online courses, and we can conclude that nowadays it’s really not that hard to get started with FP.