3.7. F#

F# is a functional programming language for the .NET Framework that was previously available as a separate download to Visual Studio, but now comes included in VS2010. Some developers feel that functional languages such as F# can enable you to work in a more intuitive way (particularly for those with a mathematical background), and are very good at manipulating sets of data and solving mathematical and scientific problems.

Interest in functional languages is increasing due to their absence of side effects (where an application modifies state as well as returning a value). The lack of side effects is vital in multithreaded and parallelized applications (see Chapter 5). Note that F# is not as strict as some functional languages, and allows the creation of nonfunctional constructs, such as local variables.

So should you rush out and learn F#? Well, it's not going to take over C# or VB.NET for developing line-of-business applications, but it is worth noting that functional languages have been influencing the development of C# and VB. An example is the recent addition of traditionally functional features, such as lambda expressions.

However, I do believe that looking at other languages can help make you a better programmer (I'm currently looking into Ruby). At a DevEvening user group presentation, Jon Skeet suggested to us that functional languages may help you become a better developer by getting you to think about a problem in a different way.

For a great introduction to F#, view the presentation at http://mschnlnine.vo.llnwd.net/d1/pdc08/WMV-HQ/TL11.wmv. Also take a look at the official F# site at http://research.microsoft.com/en-us/um/cambridge/projects/fsharp/default.aspx.