I remember my first time getting in touch with the F# language was Don Syme’s session Parallel and Asynchronous Functional Programming on .NET with F# at TechEd Europe 2007. LINQ was about to be released at the same time and - slowly but steadily - functional programming paradigms were about to enter .NET programming realms.

Nevertheless, it took me quite a while (meaning: years) to become accustomed to functional programming techniques and using them on a day to day basis. Today, a good part of the C# code I write makes use of functional programming techniques. Realizing that, I asked myself: “Why not use a language which was designed for functional programming purposes in the first place?” And F# was the obvious answer to that question.

So, quite a few years after I had come across that language for the first time, considered it interesting but hadn’t done anything useful with it, I decided to get my hands dirty and write some actual code using F#. And what can I say: the sheer beauty of code like this had me at “Hello (World)”.

There are many resources on the web making it easy to get started with that language. Just recently Try F# was launched, giving you the chance to interactively explore the language in your browser. But if you’re looking for a systematic way to explore and understand this language from the ground up, I recommend reading F# Succinctly.

This book is part of the Succinctly series, which is a series of free eBooks on different development topics, each of them covering a specific topic in a concise and pragmatic way on about 100 pages. All available books in this series can be found here.

F# Succinctly is well structured and organized, helping the reader dive into this new technology easily. It starts with the basics of installing and using the F# compiler or Visual Studio integration correctly. Also, the F# Interactive console is explained early in the book which is an important detail because this console is a tremendously useful tool for exploring the language.
After these basic steps functional programming (FP) patterns and techniques are explained. This is done in a pragmatic way providing code examples and not spending pages and pages on the mathematical background of FP. Essential techniques like recursion, pattern matching and currying are explained within a couple of pages, giving the reader just enough knowledge to get started but not overwhelming him.
With these FP fundamentals covered, the F# language itself gets explained in more detail to make the reader familiar with the language’s structure and syntax.
The rest of the book deals with integrating F# code into existing code bases written in object oriented languages like C#. This is the part which makes this book really stand out because such scenarios are the typical pitfalls for beginners. Questions like how to integrate F# with frameworks like WPF, ASP.NET or just generally object oriented libraries are covered and demonstrated using real world examples.
Finally, there is a good reference with links to websites and books providing further and more detailed information on programming in F#.

This book provides a nice introduction to the F# programming language and to functional programming in general. It can be read cover to cover within a couple of hours giving you all the necessary information to get started. And it’s free. So, there’s actually no reason for not reading it.