What is fsi.exe?

Fsi.exe is an interactive console application for programming with F#.  Fsi.exe executable opens up a window console when you double click this file after download or otherwise.

F#_00

F# is not only for Windows OS, you can use it on Mac and Linux operating systems as well.

On Windows platform it is recommended to use Visual Studio to code in F# as Visual Studio is extremely well integrated with F#.

There are a couple of ways to work with F#:

1). If you have Visual Studio 2010/13/15 Professional are higher F# is already included.

2) .Using Visual F# Power Tools can provide additional features such as :
Source Code Formatting
Auto-generating XML Docs
Highlighting
Find
Rename refactoring
Depth Colorizing
Implementing Interfaces and
many more.

3). You can also Install Visual Studio Code which is both open source and cross-platform. F# is supported by the Ionide  Project.

4). Install free F# compiler and tools alone

For this you need Windows SDK:

On Windows 10 use the Windows 10 and .NET 4.6 SDK from Microsoft
On Windows 8.1 use the Windows 8.1 and .NET 4.5.1 SDK from Microsoft
On Windows 8 or Windows 2012 Server use the Windows 8 and .NET 4.5 SDK from Microsoft
On Windows 7 or Windows 2008 Server use the Windows 7 and .NET 4.0 SDK from Microsoft
Requires Microsoft Build Tools 2015

5). Another easy way to work which does not need any download is to access this URL:

You have the choice of three languages here: C#,VB.NET or F#.




Enjoy!